Hey guys just went down in tire size fro 325/65/18 to 285/70/17 on lifted (3"terraflex) jk unlimited Rubicon. Wife called my frantic from side of road from what she described sounded like death wobble I use to get in my Early Bronco -- violent shaking.

The new tires are used but in good shape.

Do I need to realign after going down in tire size?

It drove fine before tire swap with exception of slight shimy when hitting bump.

Any suggestions or help would be greatly appreciated

 

This happened to me while I was waiting to mount my current beadlocks and 35's. I borrowed a balanced set of stock wheels and tires and during the period of a week I could not go over 45 mph without getting the wobble. It got so bad that it damaged a teraflex steering stabilizer. Oddly enough I checked everything and everything seemed to be right from my trackbar to my ball joints and everything in between. I mounted my new tires and wheels and everything went back to being solid as can be. No wobble, no shimmy, nothing. I also have a 3" lift so I don't know if the wider stance plays into the stability but running a 4.50 off set killed my death wobble. It only happened while rolling on the smaller tires and stance. Hope you can work out your issues and check everything as DW starts to damage other components if you let it go.
I went from this, to this

 

Probably due to uneven wear or poor balancing. Happened to me on a set of used winters a bought. They looked ok to the untrained eye but they were not evenly worn when looked at by a pro. I rotated them around a bit until reduced the shacking. Will never buy used again.

 

I have a used set with un even wear (8/32 8, 6, 4) and I used a bubble balancer to ballance them (I know old school fun) and I'm good till about 85/90mph

 

Ok, here's what I did today. Put brand new tires on (285/70/17). Seemed to get rid of DW but wanted to be sure. Took it to local alignment shop and guy say track bar is good and tight but inner tie rod at pitman arm is worn and needs replaced. Says cant get to it till next week.

So take it to another alignment shop. He comes back to say everything is tight ( I didn't tell him about other shops diagnosis) but says my stabilizer is worn out and has a dead spot in it.

Everything I've ever read says stabilizer has nothing to do with death wobble but only to mask the problem.

So who to believe?

As it stands now truck drives pretty decent with the exception of the slight shimy I've always had

 

Three's a charm? Best two outa three? Maybe it's time to hit up a third alignment shop and seevwhatbthey say!

 

Pull off the steering stabilizer and cycle it by hand to see if there is a dead spot.

Leave the steering stabilize off. Watch my 2 YouTube videos and do the tests I show in the 2nd video.

You will have your answers it will take less time to do the inspection tests than it will to watch the 2 videos.

 

Thanks planman. Looks like I have homework for tomorrow. And thanks to all else who posted. Funny thing is I went down in tire size since my daughter is going to start driving it on occasion. Wanted to make it a bit more manageable for her and it seems I've gone the other direction - lol. Good thing is it brought out a potential problem now and not when she's behind the wheel.