Wobble....


Yes, I said it! I just rotated yesterday and drove away with the wobble. No, not "Death Wobble" from trackbar failure, but steering wobble. The steering wheel wobbles and even the stick shift was wobbling.

It initially came in at around 30 and stayed till a little past 40-ish.

I couldn't understand how a simple rotation did it when it hadn't done it before. So I started thinking about what could be different. I did notice that my wheel pulled slightly more to the left than it had before. I deducted that there had been no change in alignment and the only other culprit must be tire pressure.

So I stopped and checked on the tire pressure. Sure enough my my driver side tires were at 25psi and the passenger's were at 30psi.

Initially the tires on the driver side were on the front. This might explain the reason that it wasn't wobbling before. I'm not completely sure.

I went ahead and aired up my tires and lowered the ones in the front by 5psi, compared to the rear, as the were sitting before. I didn't lower them down to 25psi; I lowered them to 30psi.

The wobble decreased quite a bit. It went from the span of 30-to-beyond40 to now 35-39-ish. Not bad, compared to before the airing but no were near what it once was before the rotation.

I didn't put this in the main section of the forum because I wanted to hear from you local guys first. There has been thread after thread posted on this subject and I have been reading up on them. Unfortunately they're all a little bit confusing and you really have to fish through the half-assed opinions.

So knowing that we have a few really edu-ma-cated Jeepers locally, that know me and my Jeep, I figured I'd chat with you guys first.

I'll be attempting to adjust the toe today while I change diff fluid. I've never done it before, but it doesn't really appear to be all that difficult, so I'm going to go ahead and give it a shot. Having WOL's write-up from project-jk in hand, I have faith!

The problem is, it's a shot in the dark. I know my trackbar is fine, and everything else is tight like a tiger. Seeing that most agree that the wobble comes from alignment, that's what I'm chocking it up to.

If anyone has any input it would be most appreciated.

 

If you ONLY rotated and did not balance that very well could be the issue. Swing by a tire shop and have them check the balance. Also check to make sure you didn't knock off a weight.

Bottom line, if the ONLY THING that you changed is the position of the tires and now you wobble, it's gonna be TIRE BALANCE

EDIT: FYI, the tire shop I go to does not re-balance the fronts when they rotate. They only check the balance on the rears before throwing them up front (ROTATION PATTERN C FROM E'S POST) so the rears are always slightly off but not enough to be an issue.

 

No, I didn't use any of the rotations that are listed above. I use the conveyor belt method. They all get shifted one to the left including the spare.

I upped the rears to 35psi and the fronts to 30psi.

I'll go ahead and lower the pressures to your recommendation.

 

Thanks Scott, I would have considered the balance as part of the equation but there is a side-to-side wobble and it rides beautifully outside of that speed range. Normally, at least in my experiences, an off balance tire will be a bit rough and bouncy and this surely isn't the case here. I'm not saying you're wrong by any means, but at the moment that thought will be cooking on the back burner.

 

so you have one rear tire up front? If that rear tire was out of balance before the rotation, you may not have been able to feel the vibration. An out of balance tire in the back can go unnoticed for some time before it makes itself evident. Then it's usually felt in your ass (as seat vibration)

Tire shop, check your balance dude

 

I got Mickey Thompson MTZ's not too long ago in 285/75/16 and right out of the shop the ride was horribly wobbly - and I had just had 'em balanced then an alignment done immediately following.

I was stubborn and drove it like that for about a week until I went out to Citrus County to play. While there I decided to check my TP and air 'em down for a smoother off-road experience. I took 'em down to 27.5 in back and 26 in front.

When done playing I was too lazy to air 'em back up to the 30psi range and man was it a HUGE difference in ride quality on the way home. HUGE difference - the wobble was gone.

Why yours would ride fine under higher pressures before the rotation, I dunno. I'm just giving my 2 cents to the fact higher/recommended pressures on bigger MT type tires is so you can get the distance life they promise on spec sheets NOT so you can have good ride quality; To get that you gotta accept they might wear out sooner than spec b/c you'll be running slightly lowered psi. For me, longer tire life isn't worth being frustrated with a harsh ride for the 90% of my time spent on pavement.

Best of luck diagnosing

 

Haha! NOPE! None of the above! Imagine if you would you're looking down on the Jeep as a circle or a clock, and move ALL the tires counter clockwise. That's the one!

Yeah you are right! But remember its not a vibration at all. The wheels literally wobble in a side-to-side motion.

 

I'm thinking that the lower pressure tires change the tire dimensions just enough where it changes alignment and pull. There was a marked difference in the wobble with the difference in psi.

 

I thought about it breifly when I got my ProComp as this is a half-assed decent way to rotate in your spare. I just decided to NOT rotate the spare in

 

Yeah, it's a new and improved idea on rotations of yore. Brought to you by yours truly

At the moment I'm going to be following the general consensus that the toe-in needs adjustment. That's where my thinking is and where my initial efforts will concentrate on.