If the tahoe is rockin....

[tsb09000]

...slow down!

So here's my problem. When I'm out on the highway everything is fine (somewhat smooth anyway) until I hit 70mph then the tahoe starts rocking back and forth until I slow back down. It's worse with any weight in the back (people, coolers, etc) so I think it's a rear suspension problem. I checked the sway bar end links and one of the bushings had worked its way out a little so I fixed that and nothin. Could it be a bad shock? I really have no idea, I've never experienced this.

 

[Wake]

Bent wheel or axle maybe? It would definately be something that is more noticable at higher speeds.

I found out I had a bent axle on a Camaro I owned after a shop told me about it. I put it up on blocks and put the car in Drive and let it idle. Speedo got up to about 30 mph and I could see one of the rear wheels wobbling. I new rear out of a junk yard doner cured the problem for me.

 

[Sasquatch]

Did you check on the panhard bar bushings?

I`m not sure if that would cause the problem you`re having but it`s worth checking out.

 

[tsb09000]

Well I did a quick visual and everything looked ok but like I said it was just a quick look. I did play with the tire pressure a little and took it out on the highway and it seemed a bit better but it's hard to tell without people in the back, plus I still think it's something more suspension related. Could it be as simple as a bad shock?

 

[owner]

Sounds like a supension problem, but hard to tell without actually seeing the vehicle in question.

 

[tsb09000]

Well I've put on new belltech street performance shocks at all four corners, new jounce stops in the front and new sway bar end link bushings in the front. All of this helped a little but the problem is still there. I've had three different sets of wheels and tires on it and it stays the same. I do need an alignment but I'm not sure that would cause the rocking back and forth at higher speeds.
The bushings that actually go around the front sway bar appeared to be ok but is this something to look into?

Again the problem is when I hit 70ish mph and hit a bump/dip in the road or if I jerk the wheel the tahoe rocks from side to side. It feels like it's in the rear and is more evident with people or weight in the back. I can get it back under control by slowing down or slightly "swerving" left to right within my lane.
It's hard to explain but it feels like a boat in water.

I sure hope somebody has had the same problem and it's an easy/cheap fix!

 

[Donnie Yukonie]

I would start with an alignment if you already know one is needed, You be surprised what you get with mis aligned wheels a problem in the back may actually be a problem coming from the front and your feeling newtons law. I know some vehicles actually require a 4 wheel alignment . However with a solid rear axle I doubt this is the case Though Ive never owned a NBS truck.

If an Alignment doesn't fix this I would have to point the finger at the sway bars themselves a rock from side to side won't be caused by bad shocks as they control vertical movement where as the sway bar is lateral

 

[Drippin Wett]

You can't feel it in the steering wheel any? It sounds like Death wobble, but in the rear. I'd also suggest an alignment just in case. Good luck, keep us updated.

 

[tsb09000]

Nope, can't feel it in the wheel.

I do believe my ISS is making some noise but I haven't read where it causes anything but noise. Either way, I plan on eventually replacing it as well but wondering if I should do that before or after the alignment.

 

[Matt06Yukon]

Driveshaft. U joints. Pinion bearings. Check these.