Question: C-4 Rear End Assembly

[Blue89]

I'll keep checking!! They didn't ask me to tie my shoes but they did drop the keys so I had to pick 'em up!! :booty

 

[boomdriver]

When I got my first C-4 it went to the dealer for everything. Until,. I picked it up after a warranty replacement of the EGR valve...
I look to see an intake runner dented around 1/4" deep and a good 3/4" around. I said something about it and their first response was that it would not hurt anything. After some lengthy debate THEN their claim was that it could have been like that when it came into their shop....
I eventually got a new runner but it took calls to GM and LOTS of complaining. Have not had a "stealership" touch my car since. That was 1988.

This rear end issue might just be worn out bushings. The "rubbing" on something is curious...
To a dealership service writer that means a new batwing, diff, toe-rods and all the control rods. Ya don;t "fix" anything at a stealership, you replace it. Reasons of liability as well as generating revenue. Replacement of parts places the liability on the mfg and relieves the shop of the responsibility.

Wish we had some pics or even a defective part to consider in this case. I know this group could help.

 

[Blue89]

I have it backed up on ramps, which is as good as my equipment goes and still very little clearance but I'll give it another look (I've already looked it over three times). Maybe with a microscope and a brighter light, I'll find something and again if I do, I'll snap shot it to no end......it's unbelievable the help I'm getting on this, I really, really appreciate it.

 

[vetteoz]

I have it backed up on ramps,

Get the weight off the wheels and start shaking things , any worn bushes will be obvious
Especially check the bushes on the trailing arms shown ( flog out badly with age ) and either end of camber arms under diff. All of these serve to locate wheels in correct position

 

[Blue89]

Great pic, thanks. I'll roll it out of garage tomorrow and maybe soak it down with some gunk and pressure wash as much as I can so I can see better. You're right about taking the weight off and shaking things, I should have already done that instead of standing there staring at it.

 

[boomdriver]

Yep, sometimes it just seems like all you can do is stare at it...I know, I just went thru that with an a/c problem.

Use care when degreasing or cleaning the rear end. That composite rear spring will crack if exposed to ANY acids or many other cleaning solvents. GM has a bulletin on that. I do not think that normal soaps or detergents will hurt it. I plastic coated mine to protect it from exposure to the aluminum cleaning products that I use on the underside.

 

[vetteoz]

You're right about taking the weight off and shaking things,.

For a short period of time it doesn't harm to support the frame forward of wheels and let whole rear suspension "hang".
Much easier to see movement than when supported by bottom camber arms each side as usually recomended

 

[Kenny]

Looks like that dealer wants to get into your pocket any way they can. Get a 2nd opinion.

 

[Blue89]

Appreciate the tips, cleaning, hanging, pocket........

 

[vetteboy86]

Appreciate the tips, cleaning, hanging, pocket........

Are you familiar with the appropriate procedures for lifting your C4? If you have any questions or doubts there is good information here. Let us know.

 

[Blue89]

Caught the article on "How to Jack a ZR-1", I'm assuming that's the best one. Haven't had too much time to sit with it today, family stuff, ya know!! Thanks.

 

[jonszr1]

having 3 zr1s i have done thru all ther rear end stuff. firdt off i would get a factory service manual. it tells what get taken apart and how .as well as how to ck things . everything on the rear end is easily worked on except for the differental. things that go on these cars after 100k miles are u joints on the 1/2 shafts (replace with 799 series spicer u joints ) please dont get u joints with zerks( it weakens them ). the rear wheel bearings, and as stated by others the bushings. if you are mechanicly inclined at all you can do all of the replacing of u joints bearings and bushings in about 8-10 hrs , if you allready have the parts . i would also consider poly or poly graphite bushings . if not have one of the vet guys in your area direct you to a good vet shop that will treat you fairly. i would also call the dealership and ask for the general mgr or owner and share with them the way you were treated . people who treat customers like you were treated shouldnt be in the car industry in my opinion . the owner of the dealership ,i believe wouldnt condone this type of treatment of his customers . if nothing else tell your friends who have gm products to stay as far away from this dealership as possible. you might save a friend a lot of money on their car repairs . hope this helps and enjoy your car

 

[Blue89]

OK, guys (& gals!) here's the bottom line, finally. I found the problem and solution to the situation. As indicated in the pic, I'm assuming that this is probably rare!! How it happened is anyone's guess. I found a gentleman who sold me just the part that I needed and he found me a REASONABLE mechanic (Midland Tire in Midland Ohio) that would fix it (also installed my Borla's and resolved a couple of other issues). I'd like to say at this point that he is not only an auto mechanic but a Vette owner and enthusiast and on a scale of 1 to 10, I'd rate him about a 12. Anyone in the area having problems, I'd definitely recommend him. Thanks to all for all the help, I really appreciate it.

 

[aboatguy]

Broken Batwing.......Looks like the dealership may have been honest...



Mike

 

[Blue89]

OK, I'll agree with the honesty about the driveability but not the quote they gave me for the repair! I got it fixed for much, much, MUCH less.......