Quote:
Originally Posted by Gravel
Yes... I agree with you YOM, the post was written to inform the PO that wheel alignments do very little since the toe can't be adjusted on the JK and without adjustable UCA's and adjustable LCA's there is nothing to adjust...
Worn parts may and can cause the onset of DW but are not the cause, from what I have read the only contributor to DW in the JK is a worn track bar/mounts/bushes or bent, which allows the vibration caused to amplify uncontrollably.
X2
If the shimmy or whatever you want to call it; is between a speed range and then goes away by going faster or slower or by applying the break etc it's def not DW; its shimmy and attributed (9x out of 10) to wheel balance which in turn wears out the other bushes in the steering and suspension components (this can be caused by simply losing a weight on the trail or bending something by hitting the trail to hard) and may not be immediately noticeable.
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Nah. Here's what I think:
(you will have to forgive me here, i might use some of the wrong words, its been 5yrs since i sat in a physics class and i forget quickly
) Amplification of DW happens from worn components in the steering. Its to do with the spinning wheels and the inertia they develop when they're forced to change direction. Don't you remember when you were younger on a pushbike and getting the speed wobbles from being nervous? Same theory with the wheels on your front axle and as they are connected by a sexy stiff tie rod, it only takes one wheel to be flicking about with a little bit of wear in a joint to begin pushing the other wheel into the same motion except on the pushbike it was do with your balance and twitchy steering input. If the wear is bad enough then you get the shimmy and if it gets bad enough the death wobble. Most of the time though it is just a light shimmy (the solid axle shimmy we all know about and is normal), solved by the damper and the other wheel which didn't hit the bump still tracking true holding the wheel which wants to bounce out of control steady.
ps: i think you may have mixed up your words. the toe alignment is adjustable on the JK (but not for individual wheels).
pps: My RH TRE failed completely. This is completely "WTF" as there was no impact or stick damage to make this happen, it just plain wore out.
Jeep replaced the whole tie rod with an item that has visibly larger ends than the original unit. This tells me they know there is a problem with at least one revision of tie rods. I also have the larger steering damper now fitted, although this is just here to hide other problems rather than solve anything.
Unfortunately for Jeep this hasn't worked on my vehicle. There is abnormal movement on my RH front wheel. It visibly changes camber on bumps in the road (as in, a few degrees). This is either dud bearing or worn BJ on steering knuckle. This movement has no doubt been causing the axle leaks I get from the RH shaft too. I also get very early ESP activation when turning left at low speed (i mean ESP kicks in on dry flat bitumen at speeds around 20km/hr lol). I am working with the dealer to get the bottom of this. I'm actually going to compare the front axle sideways deflection/movement against a brand newie too, as I suspect the panhard bushes have been shagged by some of the epic death wobbling I've encountered (although they are not cracked or torn).
pps3: I was able to drive out of the shimmy which always lead to DW once at particularly low speed (60km/hr lol). It was wet and I pulled it into 4wd Hi and accelerated. Resolved it almost instantly. That was the only time i'd ever been able to fight and win it. DW later broke the 4wd lever cable off the transfer case.
There was no particular speed zone for me, shimmy leading to DW could happen anytime at any moment.
pps4: there is no movement or elongated holes in my trackbar mounts, they are sturdy.
Whoops long post eh but good discussion anyway as there is obviously alot of speculation on the subject.
