rear end movement

[crazyb1]

I had my rear right wheel bearing/hub assembly replaced last week. Today I noticed that that the same wheel was squeeking again. I also noticed that when I accelerate and decel, the rear end shifts under load, and then shifts back when unloaded. It's very unnerving when at highway speeds you shift and the back end shifts. That's not right. What gives?

[Ccmano]

What you describe was happening on my car before I changed out the rear hubs. So I would suspect there is a problem with the install that was done. Of course deteriorated rubber bushings can cause the same feeling. I would jack one rear wheel off the ground at a time, grab the top and bottom of the tire and see if there is play in the bearing or in the rear suspension bushings. You may have to have someone else watch the bushings to check for movement. Just be safe when jacking the car and use a jack stand to support the car.

[tomtom72]

I would respectfully add from an apprentice Z owner that you might also check the "C"-beam bolts? If they come loose at the anchor point at the diff housing you could get some pinion rotation...wind-up under load and un-winding under no load....the beam attaches at the front of the diff housing where the pinion gear is.

Just a thought.:o

:cheers:
Tom

[bldavis11]

I'm just curious what the outcome of this was. Bearings gone bad?

[tomtom72]

I'm just curious what the outcome of this was. Bearings gone bad?


:happy1:

[crazyb1]

I've been out of town for a few weeks. The tire place couldn't figure it out. I just lost my mechanic I've used for the past 9 years so I'm trying to find a reputable shop for the Z. I did drive it a little this past weekend and I noticed that when stopped and I pressed on the brakes, a squeek/type noise comes from the right rear axle area. Same spot as before. Maybe I missed this but could the brakes have something to do with this?

[bldavis11]

I've been out of town for a few weeks. The tire place couldn't figure it out. I just lost my mechanic I've used for the past 9 years so I'm trying to find a reputable shop for the Z. I did drive it a little this past weekend and I noticed that when stopped and I pressed on the brakes, a squeek/type noise comes from the right rear axle area. Same spot as before. Maybe I missed this but could the brakes have something to do with this?
The brakes could certainly cause squeeks. You could have a caliper that's not releasing all of the way among a number of other things. Jack the right rear and spin the tire. Does it bind?

[crazyb1]

Update and advice: Found out the new hub/bearing assembly was bad. It will be replaced. Also, the mechanic found that the rear arm bushings were cracked and worn. He's trying to replace the whole arm assembly w/bushings but he can't find the whole assemblies from Chevy, and other parts searches. Can/should he just replace all of the rear bushings with one of the available poly kits from a favorite vette catelog or should hereplace all bushings and control arms. That sounds a lot more expensive!

[bldavis11]

Update and advice: Found out the new hub/bearing assembly was bad. It will be replaced. Also, the mechanic found that the rear arm bushings were cracked and worn. He's trying to replace the whole arm assembly w/bushings but he can't find the whole assemblies from Chevy, and other parts searches. Can/should he just replace all of the rear bushings with one of the available poly kits from a favorite vette catelog or should hereplace all bushings and control arms. That sounds a lot more expensive!

Why do you need new control arms? I'm missing something. :???:

[Ccmano]

Sounds like it's time for new bushings, the vette catalogs carry them all, poly or standard. Personnaly I'd go with the poly. There's even a variety that has graphite impregnated poly. (less chance of squeeking)

Your mechanic should be able to replace the bushings only.
Hans
:cheers:

[crazyb1]

Nothing wrong with the control arms. It sounded to me like he wanted more labor to replace everything than just the bushings. He mentioned that it was easier to replace the whole thing than just the bushings. My take is he wants more $$$ thru labor.

[bldavis11]

Nothing wrong with the control arms. It sounded to me like he wanted more labor to replace everything than just the bushings. He mentioned that it was easier to replace the whole thing than just the bushings. My take is he wants more $$$ thru labor.

I'm sorry to hear that. :thumbsdo: The control arms should last a lot longer than 14K miles. Imagine if you had to replace all of them twice as often as your tires!

[cuisinartvette]

Sounds like it's time for new bushings, the vette catalogs carry them all, poly or standard. Personnaly I'd go with the poly. There's even a variety that has graphite impregnated poly. (less chance of squeeking)

Your mechanic should be able to replace the bushings only.
Hans
:cheers:
:iamwithst The bushings on the dogbones (two rods you see in front of the wheel ) wear out on these. Replaced mine with poly also, quiet a s a mouse. Also when you replace the rear bearing assy check the thin washer (I know theres another name for this part) that fits behind the bearing assy. Its responsible for some clicking noises you might get once in awhiole.

I didnt find this out til after I replaced my wheel bearings, someone said, " Hey did you know youre supposed to..." :-({|=

[crazyb1]

This mechanic says he'd rather replace arms and bushings together but he can't find the arms. He says that it's much more labor intensive to replace bushings only. This doesn't sound right. How hard is it to replace the rear bushings?

[Ccmano]

This mechanic says he'd rather replace arms and bushings together but he can't find the arms. He says that it's much more labor intensive to replace bushings only. This doesn't sound right. How hard is it to replace the rear bushings?

Actually he's right, it is more labor intensive to replace the bushings. When you replace the bushings you have to take the control arms out of the car, remove the bushings from the arms, install the new bushings and then reinstall the arms. New arms generally come with the bushings already installed.

The part I find strange is that you have a mechanic who wants to do less work, it's usually the other way around.:icon_scra

Hans
:cheers:

[cuisinartvette]

Your mechanic is wasting your moeny.,Good luck on finding complete arms. Just replace th bushings, its not that bad. If he has a press he can get it done.

[Jeffvette]

Why do you need new control arms? I'm missing something. :???:

GM does not sell busings. Their solution is to sell a new suspension piece.

[Jeffvette]

Your mechanic is wasting your moeny.,Good luck on finding complete arms. Just replace th bushings, its not that bad. If he has a press he can get it done.


He is wasting your money by trying to buy the original GM pieces. The cost for one dog bone will be more than the bushing kit.

[cuisinartvette]

http://www.zr1netregistry.com/forum/customavatars/avatar196_6.gif

=D>

[FU]

http://www.zr1netregistry.com/forum/customavatars/avatar196_6.gif

=D>

Re: rear end movement

[SC UL8R1990]

lol

[Mika73]

I did just take my Z to service. All bushings are changed to polyurethane. :)

Rear end/wheels started jumping last summer when I do ´pedal to metal´ with 1th gear. Car has been driven 121000km and its -90.

[crazyb1]

Got right rear bearings replaced under warranty two months ago. Now, the same wheel is making the same noise again. The guy who did this work said he'd replace it again but wants me to take it to a dealership to find out if something else is causing the bearings to go bad. Any suggestions? The car hasn't been abused so why would the right rear go bad three times in less than a year while the left one is fine? Was it installed properly? I'm getting tired of having this same issue over and over again!!!! He did mention that he'd put in aftermarket hub assembly and when he talked to a chevy dealer on the phone, he responded that he would replace again with OEM if necessary, still under warranty.

Crazy

[gbrtng]

Is the bearing really going "bad" or do you have a u-joint that needs help?
If the bearing has some vertical or horizontal play - an 1/8" or more at the tire face - then it should be replaced. Or maybe you connected with a bad batch of bearings; best to use the AC Delco OEM ones.

[Jason 91]

I had bad u-joints causing squeeking in my rear end and I suspected everything but that.

Jason