Slim transmission crossmember - 2.7

[5oclock]

Billygoat i will snap a few pics tonight and attempt to post them. Short answer is not a lot ,,a few mm over the modified standard member. The main increase in clearance was the reduction of the cross member thickness from about 50 mm for the mod job too 8+5=11mm for the fabricated job.The extra 5mm is a packer for the mount "caddy" to sit on.So extra under fab member 50-11=39mm. The transfer still hangs lower than the frame rails but not a lot compared to standard.Infact its difficult to see it now.I am still hoping to weld the auto to transfer adapter up a bit which will give me enough meat to redrill the adapter to "clock" the transfer. The main missgiving on this is all that weight and torque hanging off the welded adapter. However, i am leaning towards supporting the transfer with another small crossmember and mount attaching to the plate that holds the vibration dampener weights. This would also help hold a decent bash plate for the transfer. Anyway i need to take a heap of pics and then try my luck at posting it up,,,be patient , i will do it.

[5oclock]

Some pics
First pic is standard vs modified
Second is fabricated sitting on top of standard cross member
Third is fabricated cross member.
Took me a long while to take some pics and up load then get them in a post.Now i have done it once i might remember how to do it again! By the way this is not a criticism of the forum,,just me getting my head around how its done. So i will post some more(hopefully a bit better) pics with a few dimensions soon.

[5oclock]

Ok, just back from the mates place who has same 2.7 crd, but with standard crossmember. Tried taking some pics but the combination of my cheap phone camera and my lack of patience for such stuff was too much and no decent pics resulted. However i got out the tape for an old fashioned approach ,and lets face it the numbers tell the real story anyway!! What i did was measure ride height on all 4 wheels from the bottom lip on the mud guards to the center of the the wheel, and then the lowest point on the transfer to the concrete and the same under the crossmember. Now it looks like my suspension is 25 to 30mm higher than his so that is reflected in the numbers...
Mates 2.7...RHS rear 485mm, front 480mm, LHS R 488, F 490
Lowest point on transfer to concrete 240mm, crossmember 240mm
My 2.7...RHS R 510mm, F 505, LHS R 520, F 520
Lowest point transfer 300mm, lowest point crossmember 325mm (320mm if i measure from bolt heads).
The Real Numbers,,,my jeep is between 25 and 30mm higher(depends which side), so deduct say 30mm from the numbers. Crossmember 325 - 240 = 85mm,deduct 30 = 55mm extra over standard.
Transfer case 300 - 240 = 60mm, deduct 30 = 30mm extra over standard. Which is a surprise, because parked side by side it looks a lot more than that!
Anyway after i clock the transfer it will be the crossmember that is the lowest point,,,,except for the exhaust, in particular the muffler!
I did lift the exhaust a bit with modified brackets at the new crossmember , other wise the exhaust would be hitting on the xmember.
A few points,,,i used 100 x 8 mm flat bar, its ok but its a little flexy, 10 mm might be better.
The clearance underneath from the bottom of the floor to the top of the "flywheel" looking vibe weight is about 10 to 12mm.
I removed the sound blanket stuff above the gbox ,xfer before i started on this project for a number of reasons,,,it has made the jeep a bit noisier, not heeps but a bit. One noise i dont hear any more is the undersides scraping on some of the huge dozer cuts on tracks up the bush in this area (the Hiluxes,Rangers etc will have a bit more work on their own now).
I dont think it is possible to do this mod without a double cardan on the front shaft.
Also there is a bit of mucking around to get the original gbox/trans mount in the right spot forward / rearward, on the original they all seem to be in line crossways on the xmember but on the modified xmember the mount wants to move a bit to the rear. If its not right i got a lot of vibration because the mount rubber was cocked out of line(if that makes sense).

[Adrian D]

As for strength, if you add some side panels it will help much more than increasing the thickness.

You have excellent gains with the updates. The factory caddy has slotted holes for bolting it to the crossmember, I plan to keep those.

I will start actual work on the crossmember after finishing up my MX5, I need to replace the front chassis legs and then I can finally get it back on it's wheels. No point it working on two projects at the same time:





Quite a bit of work planned for the Jeep: NP231 swap, ARB's, crossmember, exhaust...
My NP231 should arrive today or tomorrow, I think it's smaller outside than the NP247, hopefully I will find a way to connect the driveshaft without ordering a custom one.

[5oclock]

You sure have some projects AdrianD. What do you see as the advantages of the NP231 over NP247 ? From what i have read they share the same low range ratio 2.72, is it so you can go just 4x2 HI,and 4X4 HI locked Vs 4X4 HI progressive coupling "locked"??
I have kept the factory caddy , just got to cut the two bits that hang over off.

[Adrian D]

I'm switching to the NP231 because I want RWD only and a simpler t-case. When I had an XJ with the NP231 I never had trouble on snowy roads, if I need the extra traction I just switch to 4-High and away we go.

For me fuel consumption also matters because I use the Heep for going on vacations across Europe and there were several claims from Portugal (where people swap in NP242's) and one locally (swapped in an NP241 off a JK) of improved fuel consumption.

[5oclock]

Fair enough,just goes to show its different strokes for different folks. For me the 247 is great on fast gravel/dirt roads-in HI- because the progressive only kicks in when there is wheel slip front to rear and i am not getting the nasty tyre wear from solid 4x4 HI. And there is plenty of wheel slip most of the time when i am on fast gravel!!
Will you have a go at some kind of home made free wheel hub??
If it was possible to do i would be surprised if there wasnt good fuel savings.Just realised it would play merry hell with wheel sensors.
I hope the Heep was just a keyboard fat finger,,,,other wise you starting to sound like a Toymotor pilot!!!!