Random steering wheel wobble

[Runge17]

Hey there, I've got a 1991 4Runner SR5 and the problem im having is that after driving for about 10-15 minutes or after the vehicle is warmed up, the steering wheel will shake randomly. I could be going straight at about 30 mph, then the wheel will start spontaneously wobbling. And then if i make a turn or two, and go straight, it will be fine. Then after about another minute the wheel will go wobbly again, about an inch or two. The body wobbles a bit too so one of the wheels is wobbling. Any suggestions as to why it would do this? And at these random periods?

Thanks alot!

 

[markfagus]

Does the wobble go away when you speed up? I had an issue like that 2x before. Once was a wheel balance issue (that went away with speed) and the other time was due to belts separating in a tire.

 

[Runge17]

No, the wobble gets worse with speed. But then when I slow down to almost a stop and then speed up again it'll be gone. Then it'll return after a couple minutes.

Also sometimes it wobbles like hell on the highway on my way to work, but then on my drive home from work 8 hours later it doesnt wobble at all.

 

[markfagus]

that is very similar to the belt separation issue I had with tires. What shape are your tires in?

 

[Runge17]

theyre about two years old and roughly 18000 miles on them. Plenty of tread left on them and just some hairline cracks here and there on the sidewall

 

[markfagus]

Might want to make sure just to rule that out. On my tires that I had the issue with, it was a 5.0 Mustang with Z rated Michelin tires and 3 of the 4 tires had separated belts with less than 15k on them.