Tire Bouncing!

**skidmarks21** · 09-04-2013, 07:23 AM

I have a 98 Pontiac Firebird and I just replaced the shocks. I replaced them because my car just hit 100k miles and the tires sounded like they were bouncing. After I replaced them with bilstein shocks it still sounds like the tires are bouncing. I know that it is the rear passenger side not to sure about the front. I know my sway bar is cracked very little and I just wanna know if that could be making it bounce. Any thoughts.

***SMWS6TA*** · 09-04-2013, 07:38 AM

check the lca bushings. The stock stamp pieces are flimsy. Wheel hop is common with the stock LCA's

Check your spring too. make sure it's not cracked or sagging.

Crack sway bar??? explain

**2002ssslp** · 09-04-2013, 03:39 PM

I suspect it is the LCA bushings. After 100k they are ready to retire. I would go with UMI units. Top quality and excellent performance. You will not be disappointed with the price either.

**pajeff02** · 09-05-2013, 04:06 AM

Did you check your tires for a bubble or other defects?

**35th-ANV-SS** · 09-06-2013, 09:05 PM

Originally Posted by pajeff02

Did you check your tires for a bubble or other defects?

This was my first thought, then LCA bushings.

**cpop98ws6** · 09-07-2013, 11:38 AM

Originally Posted by SMWS6TA

Crack sway bar??? explain

GM cars are well known for sway bars cracking where the hole is for the links, it's almost like it is splitting apart.

OP: Make sure you have the nuts on top of the shocks tight. Sometimes toy needs someone under the car holding the shock so it doesn't spin.

**skidmarks21** · 09-09-2013, 07:21 AM

Crack sway bar??? explain

GM cars are well known for sway bars cracking where the hole is for the links, it's almost like it is splitting apart.

just like cpop98ws6 said

**skidmarks21** · 09-09-2013, 07:22 AM

No bubbles in tires just bought them and rims are fine

**skidmarks21** · 09-09-2013, 07:24 AM

Originally Posted by cpop98ws6

GM cars are well known for sway bars cracking where the hole is for the links, it's almost like it is splitting apart.

OP: Make sure you have the nuts on top of the shocks tight. Sometimes toy needs someone under the car holding the shock so it doesn't spin.

I have all nuts. Do you think that could be the problem cause it is cracked?

**pajeff02** · 09-09-2013, 05:19 PM

Are the shocks correct for the car? Is it lowered? Shocks have to be able to extend and compress from the exisiting ride height in order to work properly. If the car is lowered, the shocks may be compressed upon install once you set the car back down on the ground.

**skidmarks21** · 09-11-2013, 07:31 AM

Originally Posted by pajeff02

Are the shocks correct for the car? Is it lowered? Shocks have to be able to extend and compress from the exisiting ride height in order to work properly. If the car is lowered, the shocks may be compressed upon install once you set the car back down on the ground.

Everything is correct for the car, No its not lowered. My brother and I installed them and he has done it before on his car (98 pontiac trans am) his name is sirenformula350. The only thing I can think of is my crack sway bar or if its not tightened all the was down.

**pajeff02** · 09-11-2013, 08:18 AM

I can't imagine how a cracked sway bar could cause a "tire bouncing" sensation.

**cpop98ws6** · 09-11-2013, 10:37 AM

I'm with Jeff on that one, never heard of a sway bar causing that.

**35th-ANV-SS** · 09-11-2013, 10:52 AM

The things that control the rear tires and how they are planted to the ground are: Torque arm, lower control arms and shocks/springs. If the tire is new and in good shape, I'd be looking at the lower control arm first (tight/torqued to spec), not bent or damaged, bushings in good shape... then from there the shock/spring installation. Lastly, the torque arm. The torque arm controls the rotational movement of the rear end assembly so it's likely a problem with that would not result in a problem on just one side.

**pajeff02** · 09-11-2013, 06:31 PM

Just for giggles, open your hood and your hatch so you have something solid to push on. Go around to all four corners of the car and bounce it on its suspension by pushing down sharply and letting go. See how it reacts and if you can feel a difference at any of the locations.

**skidmarks21** · 09-11-2013, 07:08 PM

Originally Posted by 35th-ANV-SS

The things that control the rear tires and how they are planted to the ground are: Torque arm, lower control arms and shocks/springs. If the tire is new and in good shape, I'd be looking at the lower control arm first (tight/torqued to spec), not bent or damaged, bushings in good shape... then from there the shock/spring installation. Lastly, the torque arm. The torque arm controls the rotational movement of the rear end assembly so it's likely a problem with that would not result in a problem on just one side.

Thanks I will see if any of those are the problem.

**Nitro13** · 02-05-2016, 09:03 AM

I just came across your thread so you may have already solved this. I noticed no one mentioned tire balance. Wheel weights are easy to lose be it brushing a curb, a pothole, or even driving in the rain. I have had this happen to me before where it effects only one tire. Also this condition gets worse as your tires wear.