Rear end bouncing

[BLACKMARAUDER04]

Well i just replaced the lower control arm bushings,an alignment, front rotors and brakes, 1 stud that was broken and an oil change.

However, the car feels like the rear wheels are skating on ice.
Its very slippery and bouncy. I looked the car over while it was in the
air and everything looked all right back there. Any ideas?

I have KYB shocks all around.There is 114,000 miles on the car.

I fell very unsafe on the freeway over 70. On asphalt, it is much smoother. Vey little bouncing and it doesn't feel like its sliding around on ice.

http://www.mercurymarauder.net/forums/images/misc/progress.gif

[fastblackmerc]

Well i just replaced the lower control arm bushings,an alignment, front rotors and brakes, 1 stud that was broken and an oil change.

However, the car feels like the rear wheels are skating on ice.
Its very slippery and bouncy. I looked the car over while it was in the
air and everything looked all right back there. Any ideas?

I have KYB shocks all around.There is 114,000 miles on the car.

I fell very unsafe on the freeway over 70. On asphalt, it is much smoother. Vey little bouncing and it doesn't feel like its sliding around on ice.

http://www.mercurymarauder.net/forums/images/misc/progress.gif
How are the rear control arm bushings? Shocks? Did you turn off the air bags before you put it in the air?

[SpartaPerformance]

When did this start, was it before or after the service you performed?

[burt ragio]

As mentioned check rear upper & lower control arm bushings. Also check watts link bushings.

[BLACKMARAUDER04]

The air bags are fine. I turned them off before service, and back on after.
I saw the car rise and lower when I turned the engine off.

KYB shocks look good. Tires are all balanced (had them checked). I have Z&M rear control arms.

It started before the service, but I thought it was do to the control arms.
On smooth asphalt it is much calmer than on cement. Also at slower speeds there is no problem. Its when you get up to 70-80 MPH that there
is a problem.

[ctrlraven]

Stock or Addco sway bars?

[liquid]

Were the control arms and links tightened at curb height, or when the wheels were at full droop?

What brand of tire and how many miles?

[Blackened300a]

What rear tires are you running and how much psi?

[SpartaPerformance]

Check tire pressure! Also were the tires balanced recently? Sounds like you may have a shifted belt.

[BLACKMARAUDER04]

Stock sway bars are on the car.
I have new BFG's on the rear (2000 miles)
and BFG fronts - (14000 miles)
Tire pressue at 35 all the way around.
I had all 4 tires re-checked for balance. THey are perfect.
Like I said it happens on cement more than asphalt. Asphalt is a very smooth drive.

What is a shifted belt?

[fastblackmerc]

Stock sway bars are on the car.
I have new BFG's on the rear (2000 miles)
and BFG fronts - (14000 miles)
Tire pressue at 35 all the way around.
I had all 4 tires re-checked for balance. THey are perfect.
Like I said it happens on cement more than asphalt. Asphalt is a very smooth drive.

What is a shifted belt?

Take the rear tires off and let them roll across a flat surface, if the belt(s) have shifted them you'll see the tire wobble.

[BLACKMARAUDER04]

I saw them spin on the balancing machine. They spun straight.

[RF Overlord]

Were the control arms and links tightened at curb height, or when the wheels were at full droop?I vote for this one...sounds like a bushing binding.

[GreekGod]

KYB shocks look good

Shocks can go bad and still look good. I suspect a bad shock absorber.

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[Krytin]

Shocks can go bad and still look good. I suspect a bad shock absorber.

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+1 on that
How many miles on the shocks?
Second guess is a bad tire.

[BLACKMARAUDER04]

New update:

Well after driving for almost 2 months with the new BFG rear tires I went back to Costco. We decided to put on my spare tire I keep in case I have a tire failure so I don't have to drive on the mini spare.
So, they installed the spare tire on my left rear wheel. I took the car for a drive, and the left side was smooth and not bouncing everywhere. Went back 2 days later, talked to the person who was helping me and they agreed with me that the tire was defective. Well the right side has been bouncing also, but not as bad as the left side. After discussing it, they decided (agreed) that both tires were defective. They ordered brand new ones for me. They should be in tomorrow (Tuesday).

If anyone else is having this same problem, please get them checked immediately. When we spun the tire slower on the balancer. you could
see the center of the tire and they looked like they were not right.

Thanks to the tire guys at the Northridge Costco for not thinking I was
cracked up. Since I'm the only Marauder they have ever seen, they like
to take care of the cars tires.

[fastblackmerc]

Hmmmmm...

So just like I said in post# 11.