95 XJ shaking at 85km/h

[skiman]

G'day Jeep gurus,

i've noticed a significant shake on my 95 XJ from 85km/h onwards. I cant drive through it, and if anything, it seems to get worse the faster i go. Its not a shake in the steering wheel, its more in the body. Also, it sounds like there is a "groaning" sound coming from the back left when the Jeep first starts to roll - i thought it was the muddies at first, but the steering mechanic noticed it as well. Not sure if this is related to the shake.

Have only bought her a few days ago, so im ironing out the issues as i find them.

It has a 3.5" lift and 33" muddies.

Things ive done so far:


Had the wheels balanced (twice). They were out, but it didn't fix the shake.
Wheel alignment. Was out a little, but didn't do anything for the shake.
Wheels and tyres were checked and they're ok (2 rear rims are a little banged up but nothing too significant).


First mechanic said everything looks good underneath and is tight/ not worn.

Took it to a reputable steering and brake dude in town and he said he couldn't find anything wrong with the steering side of things that would cause the shake. He recommended a rear drive shaft balance.

I went for a search through this trusty forum and found a few other guys who have had similar problems.

Can you guys please suggest what the next most obvious (and hopefully cheapest) thing might be? From what i've read, it could be:


Front drive shafts
Front axle yolk(?) (whats a yolk?)
Front uni joint (seized or worn)
Rear drive shaft
Rear uni joint
Rear diff has rolled changing pinion angle (whats a pinion angle?)


I have no idea how to check any of them, lol. Don't have much experience with mechanical things or 4WD's but am keen to learn (im a computer geek) ;)

Can you guys recommend a good mechanic in Wagga that could fix/ troubleshoot the problem for me please?

Would really appreciate any advice or assistance.

Cheers

Skiman

[junglejuice]

Firstly to make it easier to give advice or assistance we need to know some "actual" details, so you state it has a 3.5" lift, can you verify this?
Stock is 17.5" F and 17" R when measured from centre of the rim to the underside of the flare, so lets start with that measurement as that can be a guide to the vibration, ie driveline vibe will often come in around 80-90 on cars with anything from 2" or more lift (vehicle dependant)....

[Dustbowl]

Like JJ said, you should also note lift can make your front axle on your control arms unbalanced by changing the angle between the control arms and the diff, like shopping trolley wheels, you may want to look into a long arm kit, or at least longer :p

I have a mate with a 6 inch lift on 35's with stock arms (its pretty dodgey but scary capable) anyway he has no angle issues, but you know with XJ's one thing is certain... What fixes a problem on one will not fix the same problem on another ;)

[thechief]

My 95 xj got a crazy wobble like you are describing. My front brake disc was warped so when i braked the whole car shuddered. One day i was stuck crawling in traffic for about 2 hours.i went to get up to 100ks again and by 80 the car shuddered that bad that the hub cap on the passanger wheel flew off. My brakes were binding and not letting go coz the disc was warped. Maybe a similar problem with yours?

[justjeeps]

I know that jeep as been like that for years thought last owner would of fixed it i never had a good look at it but it was running 35" tyres when it first come to town so are you sure it's only 3" of lift. Has it got sye kit or just trans drop ? Are the front control arms adjustable ? Track bar is it adjustable ? Really hard to say without looking at it.

[BLAKLISTED]

Ever been in a prang?

[skiman]

Thanks for the help and suggestions guys and sorry for the inaccurate/ lack of info. Will try to answer as best i can. :confused:

The distance from centre of rim to underside of those black flares it has is: 23". So if stock is 17", does that mean i've got 6" lift kit?

Wheels are 33 x 12.5 x 15.

Previous owner said that it hasn't been in an accident, but when i did the revs/ vehicle history check, it was flagged as "write off" due to collision. As previous owner was a mechanic, he assured me that everything was straight, welds good and no issues or evidence of a collision. The definition for "write off" on the car history site said that usually that happens when the car is not economically repairable. Write status was in August 2003.

Justjeeps - i would have thought so too. Good questions mate. Im not 100% sure, but comparing to internet pictures and searching google for those part names, i would say:

Front control arms - not adjustable. (see attached pic)
Track bar - is adjustable. (see attached pic)
SYE or trans drop - no idea. See attached photo if that helps?

I wouldn't say its a wobble, but more a higher vibration. It happens when the brakes are cold or hot. I really dont think its brakes (i've experienced that problem in another car). But thanks for the suggestion :)

http://www.ipanoramic.com.au/images/XJ/IMG_0451%20%28Large%29.JPG

http://www.ipanoramic.com.au/images/XJ/IMG_0452%20%28Medium%29.JPG

http://www.ipanoramic.com.au/images/XJ/photo%20%28Medium%29.jpg

[junglejuice]

Ok you have a SYE fitted from what I can see in the pic, the lift measurements are null and void due to the aftermarket flares.
Generally a vibration like that is from the rear tailshaft unis due either to excessive angle or worn unis...

[justjeeps]

x2 on that rear uni joints or rear drive shaft angle. I don't like to talk bad of the previous owner as wagga is not a real big place but can tell you I would not let him work on my lawn mower. If you want to try new uni joints I have some spare's inbox me you can drop by my place or will bring them to you.

[rainman]

Are there shims / wedges between the leaf packs and the spring perches on the axel?

[rainman]

Also pull rear drive shaft and go for a spin in 4wd. See if problem goes away.

[skiman]

Thanks for your help gents - love your work! Am learning heaps! :D

Is there another way to check how much lift it has? Im curious now. The aftermarket flares are very close to the lips of the inner metal flare..

Rainman - I don't see any shims or wedges between leaf packs or spring perches on axel. Pic attached.

http://www.ipanoramic.com.au/images/XJ/IMG_0453%20%28Medium%29.JPG

Here's a pic of the rear drive shaft.

http://www.ipanoramic.com.au/images/XJ/IMG_0455%20%28Medium%29.JPG

I like the idea of removing the rear drive shaft to eliminate that possibility.

So if the problem goes away, does that mean there is a problem with:

a) rear drive shaft balance
b) rear drive shaft angle
c) rear single uni

Might be a silly question, but since im driving in 2WD, should the rear drive shaft NOT be spinning? Its the front drive shaft that works all the time yeh?

To remove rear drive shaft, is it as simple as unscrewing the u-join strap bolts as per this photo?

http://www.ipanoramic.com.au/images/XJ/rear%20shaft.JPG

[BLAKLISTED]

I thought drive was sent to the rear when in 2wd, thus rear drive shaft used while front is not used till in 4wd.

Your right, remove rear c clips at the diff end but also take out the four bolts at the flange end/gear box end and the rear Ds should pop out. Once this is done, Whack it in 4wd and go for a drive and see what happens.

correct me if I'm wrong all ye wise ones.

[rainman]

Yes on removing the rear drive shaft with the straps, will also have to unbolt the flange on the slip yoke eliminator.
In 2wd all the motive force from the engine goes down the rear drive shaft. The front drive shaft turns but only cause it is attached to the front wheels, witch are turning when you drive. The front DS is not attached to the engine in 2wd. -did I miss understand the question?

Jack the car up, put it on 4 stands, in 2wd see if you can get the noise to appear, if not see if the noise will appear in 4wd. If you have access to the stands, otherwise-

If not pull rear DS and go for a spin, with out shims between the leaf pack and the spring perches, would be suspecting vibrations because of drive line angles.
How tall are the front spring spaces at the top of the coil springs?
Is there a part number written on the top leaf of the spring PAC?
To me it looks like rubicon express non adjustable front controll arms. And a RE slip yoke eliminator.

Kind of looks like a budget lift, ie spring spaces in the front and extended shackles in the back over stock springs. Original length brake lines, back yard lengthened sway bar links.

[Toff]

Rear Pinion looks too hight.
With a SYE the pinion should be pointed about 1deg below the tailshaft.
The pinion climbs under load.
You'd looks pointed higher, thus under load will clibe higher again.And I don't see any shims that normally would be there.

As for the kit it looks like an RE 4.5" to me. Although are thouse stock front Hoses? Really should have longer hoses fitted.
And it doesn't appear to have extended bumpstops either - would suggest fixing that.

[junglejuice]

X2 on the pinion being too high, it appears that it is higher then the tailshaft which is a no-no.
As for lift height, measure from the lower lip of the metal upper bump stop cup to the metal pad inside the front coil and post up this measurement, I have some measurements written down somewhere that I can compare and give you an actual front lift measurement, as for the rear measure from the axle tube to the chassis rail above the bump stop and post this up...

The other thing to remember is your rear tail shaft is different to the drawing that you posted and is removed differently as mentioned above....

[skiman]

Streuth! Most of this is going over my head gents & not quite sure what I should be doing next. Sounds like there are a couple issues that need to be checked... So I'm wondering if I should take it into a local mechanic & get someone with a trained eye to look it over it?

Question is, will they know whether the lift kit has been done properly? Will they know what the correct DS angles are?

If the drive shaft angle is causing the shake, is that adjustable/ repairable?

Can anyone recommend a good 4WD mechanic in Wagga?

So many questions, sorry gents. I've definitely taken up my quota!

[rainman]

Mate I'm really seeing one problem here. Rear drive shaft/ drive line angles.
Fixed by installing shims/ wedges- which you buy in a kit, got mine from Wooders.
Suggest, pull drive shaft, take for spin in 4wd this should verify the problem.
Take measurements as described by Jj. This will give total lift height.
2 hours tops. And you are half way to fixing it.

later you will proly need and angle finder as well, download one of the net for your smart phone, one of the guys will take you through how to use it. two measurements a bit of addition and subtraction you will know what you need.

[skiman]

Thanks for the encouragement guys - i need a kick in the arse sometimes ;-)

So i've pulled the rear DS out this arvo and took it for a spin in 4WD Part Time. NO VIBRATIONS! :D

I noticed that the green 4WD Full Time selection would not engage - is that normal if the rear DS is out?. Also noticed that none of my 4WD indication lights are working - will add that to the future fix list.

So.. it looks like i need to shim/ wedge up the rear springs. I'll order a shim pack from Wooders tomorrow. Can you guys direct me to any instructions on how to do this please?

That measurement in the coil from the bottom of the bump stop cap to the lower metal pad is 9" (23cm).

Is it worth getting the rear DS balanced/ checked whilst its out?

When i removed the clamps from the back uni joint, i rounded one of the bolts (but still managed to get it out, w00t!). I figured this would be a good time to replace the pinion yoke - anything i should know before i pull it out and replace? Thanks to Justjeep (who has helped me out heaps here in Wagga - bloody legend!) - he's supplied me one of the new yoke designs with the u-bolts. A much better design! :D

So when that drive shaft goes back in, im ready to measure some angles. What iphone app do you guys recommend please?

[BLU-125]

While talking to Wooders, see if he has a replacement u-bolt style yoke in stock, as well as the wedges.

[skiman]

I've already got the replacement yoke and u-bolt assy from Justjeeps today. :) But thanks for checking BLU!

[junglejuice]

Whats the measurement for the rear height from axle tube to the underside of the chassis rail?
If you drive on the front shaft you need to use "part time" 4wd as it locks the centre diff, if you use "full time" 4wd it leaves the centre diff unlocked and all that will happen is the rear output shaft will spin with no drive being sent to the front wheels.

I don't know about iPhone apps, I use android and used to use Symbian and there were angle finder apps for both OS's but I bought a proper magnetic based angle finder.
Check to see if there is anything between the leaf packs and the spring seat on the diff that looks like a wedge shape, if there is then you already have the wedges fitted, just the wrong size.
Do you have extended shackles fitted?

[rainman]

iPhone clinometer
Would not worrie about the rear DS to much at this stage, just a quick check for gross obvious damage of the shaft and unis. It is quick to pull and the car is drivable with out it- if probs persist.

[greeno]

Hi mate first off great looking Xj and looks like it's had some good parts put into her but you do have a couple of things to fix or you'll damage what you have mate
First off you need to fix up the rear springs and rear brake lines( shackes are home made and look way to long ) drop her down a inch or two use a set of jks shackes this should fix your vib's at the same time ( don't buy shims to you have done this )
Drop the front down the same amount by pulling some of the packing out from the top of your front spring mate ( easy job to do ) and move your front brake line down
make up some new bump stop front n rear and go have a ball in her
Have a look at gojeep site it will help you mate

[rainman]

http://www.go.jeep-xj.info/HowtoD44RearAxleInstall.htm

http://www.go.jeep-xj.info/D44Axle09.jpg

http://www.go.jeep-xj.info/D44Axle03.jpg

[skiman]

Junglejuice - thanks for explaining about the 4WD modes mate.

Measurement from top of axle tube to underside of the chassis rail is 32cm. Definitely no wedges on the leaf springs.

So is the idea to put wedge(s) between the flat part of the axle and the leaf spring above, so as to roll the diff on a higher angle, thereby decreasing the angle between the drive shaft and the pinion? (tryin to get my head around this). :confused:

I measured the angles with my iphone using the clinometer app - thanks rainman.

I put my phone on top of the drive shaft and got 19.7 degrees.

I then put my phone against two adjacent bolts on the rear diff (as per rainman's first pic below) and got 63 degrees.

Does that seem right?

Greeno - thanks for the suggestions mate. I'd really prefer to keep the lift where it is, if i can help it mate. I understand i've got a few things to fix if that's the case.. but i think they're (hopefully) small fixes. For eg, i can make an extension bracket (http://jeep-xj.info/HowtoBrakeExtension.htm) for the brake line.

Pinion yoke replacement - have hit a brick wall on trying to replace this. After checking the service manual, i quickly realised i dont have any of the necessary tools :( So will probably need to call transmission place tomorrow and see if they can pull old one out and fit my u-bolt version yoke and the new seal. I feel like i've copped out on this one. :oops:

Just want to express my gratitude to you guys for all your help and patience. Means a lot to me. If we meet in person some day, beers will be on me http://www.ipanoramic.com.au/em/beer.gif

[mato]

sound like death wobbles or possibly bad drive line vibration
check you front track bar mount at the diff you want no moment well almost nothing
here on YouTube you can see some bad ones
http://www.youtube.com/watch?v=LjzRgvxclVw
http://www.youtube.com/watch?v=rlnrLiCE3ss

and another easy trick. do you have transmission spacers
http://jeep-xj.info/HowtoTCdrop.htm
you can easily make some it will help reduced the big pinion angles as which in return can also stop or slow the vibration. other thank that the next step is diff wedges.
i hope you can get it sorted
also if your worried about tyres and wheels if you have them put the stocky's back on and drive it see if it makes any difference

[Wooders]

I put my phone on top of the drive shaft and got 19.7 degrees.

I then put my phone against two adjacent bolts on the rear diff (as per rainman's first pic below) and got 63 degrees.

90-63=27°
Less 20°
ie difference of 7°.
This is a little more than I expected from the pics. Could be those rear shackles kicking the pinion up higher.

Edit: Also since you have a SYE - please don't lower the t/case ;)

[mato]

oh i did not even think about the SYE Good one wodders
perhaps get some diff wedges

[skiman]

Thanks Dave.. ill take another measurement tomorrow to be sure. So does that mean i need two 7 degree wedges?

why should i not lower my transfer case because of the SYE? Is that because it would defeat the purpose of the SYE?

Mato - thanks for suggestions mate, but have already isolated the problem to the back end. I took the rear DS out and the vibration went away.

[junglejuice]

If you lower the transfer case it will make the siutation worse, ideally the pinion should be aiming just slightly lower then the tailshaft, currently your pinion is angled above the tailshaft, lowering the transfer case will make this much worse.
Your extended shackles are causing the pinion to be aiming too high so if you intend the keep the extended shackles you need to fit wedges back to front to what most people use, you need the thick end of the wedge at the front and yes they fit between the diff and the springs.
I bought a set of wedges off Wooders that are 6*, I don't know if they come higher then that but I am sure that Dave will be able to fill you in on that one....

[junglejuice]

sound like death wobbles or possibly bad drive line vibration
check you front track bar mount at the diff you want no moment well almost nothing

As the vibration disappeared when the rear tailshaft was removed I somehow doubt that it will be panhard related...

[rainman]

with the measurements you have given by my reckoning lift is in the 6" area. That is right on the limit for a short arm lift, would be expecting steering linkage problems, track bar binding during flex. ride quality would be quite harsh-drop boxes would be an excellent idea. getting quick sway bar disconnects will also be handy.
I'm not really a fan of that extended shackel set up either.
however it is your heap not mine.
Good luck with whatever you decide to do.

This is worth a read all about modifying Xj's and what lift height beget which problems
http://www.naxja.org/forum/showthread.php?t=968708

[junglejuice]

Ok the stock heights of 17.5" F and 17" R equate to approx 90mm from the underside of the bumpstop cup to the bumpstop plate inside the coil for the front and approx 150mm from the actual chassis rail to the top side of the diff tube (dana35).

So at 230mm F and 320mm R equates to a front height of 140mm lift or 5.5" and a rear height of 170mm or 6.7"...

This is somewhat more then the 3.5" lift originally mentioned.


Removing the spacers and the shackles will save you a load of dramas and still leave you plenty of usable lift....

As rainman mentioned that sort of lift on short arms without drop boxes doesn't lend itself to a great ride.

Also keep in mind that any lift gained by spacers or shackles needs to be added to the bumpstop length to prevent over compressing of springs and/or shocks so by that I mean if you have a 2" lift shackle then you need to extend the bumpstops in the rear by 2" and up front what ever spacers are added above the coils, say 2" again needs to be added to front bumpstops, this is often overlooked and is very important....

[skiman]

Thanks for the explanations and calculations guys. Your feedback and advice is invaluable.

The more i find out about this Jeep, the more pissed im getting that the guy who fitted all these mods did such a poor job installing them all. Talk about half arsed. More the fool me for buying it without really knowing what i was buying and taking the word of a mechanic. I saw a nice looking Jeep on the side of the road and was sucked in - what a n00b! :oops:

It seems i have two options at this stage.

1) Keep the lift and finish the job properly. Install drop brackets or a long arm kit. Also need to install wedges, check brake line lengths, install longer bump stops all round, install sway bar disconnects.

2) Lower the vehicle (what would be a suitable lift height?). Remove the shackles and spacers (is that all i would need to remove?). Does that mean i would need to reduce tyre size as well?

Im more inclined to go with option 1 and finish the job properly. :? But alarm bells are going off in my head about "spending money on an older Jeep that i know im not going to get back".

At the end of the day, i want a 4WD that is capable out in the scrub.

[skiman]

Btw... where the heck did you guys learn all this stuff? I take the car to 3 mechanics here and none of them could have told me the things you guys have :) lol

[mato]

As the vibration disappeared when the rear tailshaft was removed I somehow doubt that it will be panhard related...

Yep it helps if you read the whole thing which obviously didn't do

oh and ski man if it was up to me i would go with option 1
i mean your 3/4 of the way there

[rainman]

How big are the tires? what are the diff ratios?
I would be checking your shocks as well. check that when you flex up the shock bottoming out does not stop the axel's upward movement- what bump stops are for- among other things.
I would be looking to drop it to 4.5-5.5" of lift. Ideally new springs all round (I belive the current springs are stock units) but do the rears first the fronts can wait if needs be. maybe get a 3.5"lift leaf pack and some boomerang shackels will get you close to where you need to be. - have this discussion with a specialist jeep supplier, look around on this site, ARB or pedders will be no good for you. will more than likely need different shims to what your current set up needs.
dropboxes as previously mentioned, (can maybe wait)- don't know if they are compatible with your arms- again specilist jeep supplier- that being said I believe the arms are Rubicon express (RE) and I believe wooders is the Ausi agent.
bumpstops- check out go jeep, he likes ice hocky pucks. EBAY!
sway bar dis connects- can wait. you may have to make up another back yard set if you do change the height- inexpensive.
brake lines- again move the bracket- however I think you can land a set from the usa for less than $150 I was impressed with the difference the braided lines made to braking in my heap. and if you are running a stock brake set up you need all the braking help you can get with the bigger rubber.
you have the arms, the shocks, adjustable track bar & the SYE which are a significant % of the cost of a lift. if the axels have been re-geard then that is another $3000 as well.

I will sell you second hand extended braided lines (RE brand)for the front $60 + postage if you want?

I totally agree with your attitude on spending money on your XJ. It is not an investment, once spent money is gone, you might get %30 back if you sell the parts individually.
good luck with it.

[skiman]

33 x 12.5 x 15

[junglejuice]

Looking at those extended shackles the first thing I'd do is bin them, fit some stock ones and see what height it is, alternatively measure them from bolt centre to bolt centre and post up the measurement and we will be able to give you an idea what the lift will be with stock or shorter shackles, this will most likely reduce the nned for the wedges and reduce or possibly eliminate the vibration.
Also measure the thickness of the spacers in the front and post this measurement up as well.

As for where do we learn? From other members on this and other forums and trial and error on our own vehicles...

[greeno]

Thanks for the explanations and calculations guys. Your feedback and advice is invaluable.

The more i find out about this Jeep, the more pissed im getting that the guy who fitted all these mods did such a poor job installing them all. Talk about half arsed. More the fool me for buying it without really knowing what i was buying and taking the word of a mechanic. I saw a nice looking Jeep on the side of the road and was sucked in - what a n00b! :oops:

It seems i have two options at this stage.

1) Keep the lift and finish the job properly. Install drop brackets or a long arm kit. Also need to install wedges, check brake line lengths, install longer bump stops all round, install sway bar disconnects.

2) Lower the vehicle (what would be a suitable lift height?). Remove the shackles and spacers (is that all i would need to remove?). Does that mean i would need to reduce tyre size as well?

Im more inclined to go with option 1 and finish the job properly. :? But alarm bells are going off in my head about "spending money on an older Jeep that i know im not going to get back".

At the end of the day, i want a 4WD that is capable out in the scrub.

Mate just drop her down you can run 3.5"/4" lift with 33's with your flares no prob's at all
As I posted earlier you just need to fix a couple of things and you'll have a great car most of the hard work has been done

[skiman]

Looking at those extended shackles the first thing I'd do is bin them

Apart from the height, can you please explain whats wrong with the shackles? What would be the difference between these and a set of Boomerang's? From what i envisage, both would allow the same amount of travel and perform the same job (if they were same size). Are you concerned that these are a backyard job and the welds might be crap?

My shackel measurement from bolt centre to bolt centre is 18cm. (one was actually ~18.2 and one was ~17.9).

Also measure the thickness of the spacers in the front and post this measurement up as well.

Spacers in the front are 5.2cm both sides.

I have no idea what the diff ratios are. How do i find that out? I know that the speedo reads correctly (compared to my GPS reading).

Can you recommend a handful of specialist jeep suppliers please?

Thanks for the to-do list rainman. Im going to get around to all of that; I just need to prioritise the list, and then tick things off as funds permit. I had a chat with the Mrs this evening about all this and she agrees that it needs to be done. (half the battle right there! haha) ;)

Next week, Im going to be having a chat with the guy who sold it to me and hit him up for all the info (ie, how much lift, what the diff rations are) etc.

[greeno]

Apart from the height, can you please explain whats wrong with the shackles? What would be the difference between these and a set of Boomerang's? From what i envisage, both would allow the same amount of travel and perform the same job (if they were same size). Are you concerned that these are a backyard job and the welds might be crap?

My shackel measurement from bolt centre to bolt centre is 18cm. (one was actually ~18.2 and one was ~17.9).



Spacers in the front are 5.2cm both sides.

I have no idea what the diff ratios are. How do i find that out? I know that the speedo reads correctly (compared to my GPS reading).

Can you recommend a handful of specialist jeep suppliers please?

Thanks for the to-do list rainman. Im going to get around to all of that; I just need to prioritise the list, and then tick things off as funds permit. I had a chat with the Mrs this evening about all this and she agrees that it needs to be done. (half the battle right there! haha) ;)

Next week, Im going to be having a chat with the guy who sold it to me and hit him up for all the info (ie, how much lift, what the diff rations are) etc.

The shackles are to long mate he has just made them up to get the lift
Stock Shackle are 80mm bolt centre to bolt centre
Jks/ boomerang 's etc are about 125mm

[rainman]

well looks like the front springs are not stock, with a bit of luck they may be 3.5" lift springs. hopfully the rear packs are the same.
I'm with greeno with 33" tires and the flares 4" of lift give or take will be fine.
boomerang shackels:
http://store.jksmfg.com/merchant2/merchant.mvc?Screen=XJSHACKLES&Store_Code=JKS01&Category_Code=Leaf_Spring



as jj suggested, might be simplest ( most cost effective) to pull the extended shackels replace with stocks and see what you have. Then go from there.
I'm sure some one on here has a set of stock shackels you can have for cheap- or if you need them today- wreckers?
Just for ease of comparison down the line get a measurement from the centre of the wheel to the bottom of the flare on all 4 corners before you pull the shackels/ spacers.

diff ratio
http://www.youtube.com/watch?v=RNgjS5mHI0E

[junglejuice]

Going by the measurements that you have given, removing the dodgy looking exteneded shackles and replacing them with OEM units will result in approx 4-4.5" lift in the rear, removing the front spacers will result in approx 3.5", if you were to fit a second spring isolator the front will sit at a little over 4" which as mentined above with those flares and correct bumpstopping should be fine with your tyres...

As far as the gearing goes there is two ways of making the speedo correct, the first and cheapest/easiest way is to replace speedo drive gear but this will not help the gearbox shift pattern as it will be trying to change gears at the wrong speed (assuming incorrect gearing).
The second (best option) is to regear the diffs to the correct ratio to suit the tyres, this will result in the gearbox changng gears at the correct times, maintains close to stock performance and fuel consumption unlike the first method.
What people overlook is the gearbox doesn't change gears according to the speedo, it changes according to its internal speed sensor...

[kj69]

Thanks for posting those measurements jj is that limited heights or sport?

[skiman]

Cheers Rainman and JJ - my learning curve with you guys around has been exponential. :D

Had a chat with Dave at Wooders and I ordered a set of extended shackles (http://www.wooders.com.au/index.php?main_page=product_info&cPath=370_40_171_518&products_id=449) today. What kind of rear lift should i expect with those? ~5"? Am also looking for a set of stock XJ shackles from a wrecker (or on here) as well.

How do you guys make those lift calculations please? Just so i can learn.

Im also adding a 50kg bullbar to the front this weekend, which will probably bring the front down a little. I ordered this before i knew what i was in for with the suspension. In hindsight, my money would have been better spent on drop brackets and other rectifications :-| oh well.. it would have come eventually anyway ;-)

Is there a way of telling what type of front and rear springs i have? I checked for part numbers but couldn't find any on either front or rear. The front springs used to be blue, are 37cm and have 10 turns in them. On the back, there are 5 leafs (leaves?) bundled together, but there is a 6th shorter leaf under them that doesnt seem like it was part of the original group (is that whats called an ad-a-leaf?).

Ill check my diff ratio when i jack it up tomorrow - thanks for the video rainman, that was very helpful.

JJ - im guessing that re-gearing the diff would be quite expensive?

Greeno - thanks for those measurements and the positive support mate. :mrgreen:

[rainman]

Re gearing the diff is expensive say $1500+ then when you do the back you have to do the front as well. Add another $1500+ If you want lockers that is the time to do it, PLU$ PLU$ PLU$.
I don't know which company has blue aftermarket springs.
I bought all my suspension stuff from Wooders -very happy.
The 6 th small leaf is just a spacer for extra lift, often found exclusively on the drivers side to compensate for drivers side sag. different length shackles is another way to compensate for the sag.

[junglejuice]

Thanks for posting those measurements jj is that limited heights or sport?

Those measurements are based on Limited heights, I always reference to a Limited, maybe those measurements can be added to the info section for a reference for those who have aftermarket flares, like yours, KJ...

[junglejuice]

Blue coils could be Lovells, if the extra leaf is inverted under the pack it is there to stop the pack from over flexing, OME packs often use them.

Which calculations are you referring to? If you're referring to the extended shackles then you subtract 80mm from the new shackle's centre to centre length, divide that by 2 and that is what you will approx gain.

Just remember that if you use extended shackles it will rotate the diff up at the front which is what is most likely the cause of your initial issue, the vibration.....

[skiman]

UPDATE

Have finally fitted the new 5" shackles i received from Wooders to replace the dodgey old home made jobs. Have never done a job of this magnitude on a vehicle before, so i was really stoked when it was all done (albeit 4 hours later! lol) :mrgreen:

Measurements Before:

Rear axle centre to bottom of Bushwacker:
64.5cm (left) 61.5cm (right)

Drive Shaft Angle 12.6*
Diff Angle 72.9*

Measurements After

Rear axle centre to bottom of Bushwacker:
62cm (left) 59cm (right)

Drive Shaft Angle 12.6*
Diff Angle 75.1*

http://www.ipanoramic.com.au/images/XJ/IMG_0480a%20%28Medium%29.jpg

After installing the new shackle, I found on the right side, that there was a bolt protruding from the rear bumper!! When i examined the old shackle, i noticed decent gauge marks in the steel where it had made contact. :shock:
So i removed the bolt for now until i can fit a shorter one.

http://www.ipanoramic.com.au/images/XJ/IMG_0482a%20%28Medium%29.jpg

Job all done!

http://www.ipanoramic.com.au/images/XJ/IMG_0483a%20%28Medium%29.jpg

I took it for a drive and noticed that the vibration problem has been quite reduced (but not entirely). Which pretty much confirms everyone's opinion about the pinion angle being too high. ;)

I did not make any changes to the front lift. Overall, the lift seems much more equal between back and front now and looking at the before/ after figures, i would reckon that dropping the back by 1" has leveled it out. Do you think i need to make any changes to the front lift height?

Based off those measurements, can someone confirm for me what size wedges i need to finally correct that pinion angle? From my calculation, (after fitting the new shackles) i have a pinion angle of 2.3*. Would i need a 3 degree wedge to make that angle -1* ?

Since im upgrading my diff to a D44 and regearing in the future (when i've saved up), i think its still a good idea to fix this pinion angle. The upgrade might not happen for a few months.

What should the next priority be on my repair list.. new bump stops front and rear?

[XJeepers]

Whats going on with your bake lines? Cant make it out, but something looks odd...

[Wooders]

Whats going on with your bake lines? Cant make it out, but something looks odd...
Looks like the line has been massively lifted instead of a longer hose simply being fitted.
I just hope the breather still functions.

Anyhow Anthony glad to hears it's improving.
The pinion bearings will probably enjoy the extra lubrication now too ;)
IMHO I'd suggest a 4° shim so that the pinion will be approx 1.7° below the tailshaft - which should allow for a little pinion climb under load.
Bumpstops definitely should be on your short todo list.
I'd also suggest relocating that steering dampener.
And some then some extended front brakelines (required) before getting some proper swaybar disconnects.

[skiman]

You're right Xjeepers - it does look odd.

Thanks for input and guidance Dave. Ill start looking at the bump stops and brake lines tomorrow. Time to learn a new chapter, haha. Will give you a call tomorrow and order some more parts. ;)

[XJeepers]

You're right Xjeepers - it does look odd.

Thanks for input and guidance Dave. Ill start looking at the bump stops and brake lines tomorrow. Time to learn a new chapter, haha. Will give you a call tomorrow and order some more parts. ;)

That's what I thought was going on. Hard to see on the small phone screen.

If they are hard brake lines sticking out from the diff like, I would be sorting them out pretty soon before the get bent back and split.

[mud_slut]

Looking at those extended shackles the first thing I'd do is bin them, fit some stock ones and see what height it is, alternatively measure them from bolt centre to bolt centre and post up the measurement and we will be able to give you an idea what the lift will be with stock or shorter shackles, this will most likely reduce the nned for the wedges and reduce or possibly eliminate the vibration.
Also measure the thickness of the spacers in the front and post this measurement up as well.

As for where do we learn? From other members on this and other forums and trial and error on our own vehicles...

second that one ^^

[skiman]

I received my 4 degree wedges from Wooders and fitted them over the weekend.

To rotate my diff forward and reduce pinion angle, i fitted the wedges on the front (pointing towards the rear). After i pulled the spring locating bolt out, i noticed that it was going to be too short.

So i removed the bottom leaf of the spring (because it seemed to be an added spring anyway). The locating/ aligning bolt was still too short to fit the nut on top, but at least the bolt went through all leafs. I put it all back together and measured the angles.

Drive shaft angle = 13.7 degrees
Diff angle = 80 degrees

Which gives me a pinion angle of -3.7 degrees. Is this too much?

I took it for a drive, and although the vibration is reduced, its still there at 85km/h +. :confused:

Also, looking at the leaf springs, they seem very flat (with that bottom leaf removed). I suspect the removal of that bottom leaf has lowered the back end a little more and given me too much of a negative pinion angle.

What i think i need to do is:

1) Get longer locating bolts.
2) Get longer u-bolts to hold it all together.
3) Put the bottom leaf of the spring back in.

Can one of you guys please confirm/ advise?


http://www.ipanoramic.com.au/images/XJ/IMG_0550%20%28Medium%29.JPG

http://www.ipanoramic.com.au/images/XJ/IMG_0551%20%28Medium%29.JPG

[XJeepers]

I received my 4 degree wedges from Wooders and fitted them over the weekend.

To rotate my diff forward and reduce pinion angle, i fitted the wedges on the front (pointing towards the rear). After i pulled the spring locating bolt out, i noticed that it was going to be too short.

So i removed the bottom leaf of the spring (because it seemed to be an added spring anyway). The locating/ aligning bolt was still too short to fit the nut on top, but at least the bolt went through all leafs. I put it all back together and measured the angles.

Drive shaft angle = 13.7 degrees
Diff angle = 80 degrees

Which gives me a pinion angle of -3.7 degrees. Is this too much?

I took it for a drive, and although the vibration is reduced, its still there at 85km/h +. :confused:

Also, looking at the leaf springs, they seem very flat (with that bottom leaf removed). I suspect the removal of that bottom leaf has lowered the back end a little more and given me too much of a negative pinion angle.

What i think i need to do is:

1) Get longer locating bolts.
2) Get longer u-bolts to hold it all together.
3) Put the bottom leaf of the spring back in.

Can one of you guys please confirm/ advise?


http://www.ipanoramic.com.au/images/XJ/IMG_0550%20%28Medium%29.JPG

http://www.ipanoramic.com.au/images/XJ/IMG_0551%20%28Medium%29.JPG

Hard to tell from pics, but I think those wedges are in backwards. Get a longer centre bolt and put the other leaf back in.

[XJeepers]

Hard to tell from the pics, but it looks like the u bolts should be ok, but hard to tell.

[XJeepers]

Hard to tell from pics, but I think those wedges are in backwards. Get a longer centre bolt and put the other leaf back in.

They are in backwards. Thick part of the wedge should be at the rear. ie, the wedge should be pointing to the front of the car.

[junglejuice]

They are in backwards. Thick part of the wedge should be at the rear. ie, the wedge should be pointing to the front of the car.

They were meant to go in that way due to the fact that earlier in this thread it is shown that his pinion is facing up too high so the wedges were fitted to reduce this angle.

What is the height of the car now the extra leaf was removed compared to before it was removed?

[XJeepers]

They were meant to go in that way due to the fact that earlier in this thread it is shown that his pinion is facing up too high so the wedges were fitted to reduce this angle.

What is the height of the car now the extra leaf was removed compared to before it was removed?

Cool, admit I didn't read the whole thread :hammer: