Problem-rear end- HELP PLEASE
Thread Starter
Safety Car
Joined: Feb 1999
Posts: 4,043
Likes: 342
From: Central NJ
Problem-rear end- HELP PLEASE
Need some opinions here. I have a problem with my 79 that I need to fix asap. Here's the deal- When the car gets hot after about 45 minutes of driving I start to hear a clunk, clunk, clunk from the rear end. While driving it feels like it's coming from the left, but the passanger claims it comes from the right. It happens as I'm braking and as soon as I let up on the brake to proceed. It happens 75% of the time once it starts. It also happens when turning AND going straight. It stops after about 3 or 4 clunk sounds. For some history the halfshft u-joints were just replaced, the pass wheel bearing was replaced, the brake pads are replaced. I did a test to see where the sound comes from. This is what I did- I had my wife drive forward and in reverse while I listened. When the clunk starts I flet the tire as its moving and felt the cluck equally on the driver and pass tire. It didn't do it every time. Now please can I have some input????? Thank you
Guest
Posts: n/a
Re: Problem-rear end- HELP PLEASE (tabbruzz)
It only happens when she's hot?
Here comes the obvious questions to get them out of the way for the guys who know what their talking about.. :D .. Do you have the diff. additive (2 bottles) along with the diff fluid in there.. Have you check your diff fluid? I'm guessing that a problem/clunking in the diff will vibrate it's way to the wheels. If it doesn't happen when she's cold then I wouldn't suspect wheel bearing or universal.. Have you tried draining and refilling the diff with clean fluid and addative.. Just to make sure you've done the easy stuff.. Good luck..
Here comes the obvious questions to get them out of the way for the guys who know what their talking about.. :D .. Do you have the diff. additive (2 bottles) along with the diff fluid in there.. Have you check your diff fluid? I'm guessing that a problem/clunking in the diff will vibrate it's way to the wheels. If it doesn't happen when she's cold then I wouldn't suspect wheel bearing or universal.. Have you tried draining and refilling the diff with clean fluid and addative.. Just to make sure you've done the easy stuff.. Good luck..
Thread Starter
Safety Car
Joined: Feb 1999
Posts: 4,043
Likes: 342
From: Central NJ
Re: Problem-rear end- HELP PLEASE (Koz)
I haven't checked the diff fluid, but already have plans to drain and refill it on Wednesday. It seems that bad fluid is usually a problem with sounds heard while turning. As my problem happens while turning or going straight, I really am skeptical that the fluid can fix the problem. Correct me if I'm wrong....
Team Owner
Joined: Mar 2002
Posts: 24,160
Likes: 78
Re: Problem-rear end- HELP PLEASE (tabbruzz)
I haven't checked the diff fluid, but already have plans to drain and refill it on Wednesday. It seems that bad fluid is usually a problem with sounds heard while turning. As my problem happens while turning or going straight, I really am skeptical that the fluid can fix the problem. Correct me if I'm wrong....
Race Director
Joined: Feb 1999
Posts: 19,659
Likes: 34
From: Lenoir City Tennessee
Ci 6, 8 & 10 Veteran
St. Jude Donor '05-'06-'07-'08-'09-'10-'11-'12-'13-'14-'15
Re: Problem-rear end- HELP PLEASE (wcsinx)
Since you are going to be under the car, try checking the differential bushing. If it is worn it will give the clunking sound also.
[Modified by Eddie 70, 11:47 AM 7/7/2003]
[Modified by Eddie 70, 11:47 AM 7/7/2003]
Le Mans Master
Joined: Feb 1999
Posts: 8,351
Likes: 75
From: Tampa Bay FL
Re: Problem-rear end- HELP PLEASE (tabbruzz)
I second both the fluid/additive and bushing suggestions. May also want to consider side yoke end-play if the lubricant or bushing are not the problem.
Le Mans Master
Joined: Apr 2000
Posts: 7,562
Likes: 9
From: B'Ville NY
Cruise-In III Veteran
St. Jude Donor '05
Re: Problem-rear end- HELP PLEASE (TedH)
I second both the fluid/additive and bushing suggestions. May also want to consider side yoke end-play if the lubricant or bushing are not the problem.
Good luck :)
Drifting
Joined: Jan 2002
Posts: 1,645
Likes: 11
From: Schaumburg IL
Re: Problem-rear end- HELP PLEASE (tabbruzz)
People may bark at this one, but it ihas resolved two problem rear ends in this house. I remove the rear cover, drain all fluid out, then flush it out with a can or two of brake cleaner sprayed into the rear end gears and clutch packs. Draining only does not get the sludge and chips out of the packs. Then fill "er" up with the 2 quarts of GM rear end lube and a bottle of the posi lube and drive it. Two times the clunks, growls, turning growls have been fixed.
Corvette Stories
The Best of Corvette for Corvette Enthusiasts
Top 10 Most Expensive Corvettes Ever Sold on Bring A Trailer
Brett Foote
10 Things Every Corvette Owner Needs (2026 Edition)
Michael S. Palmer
8 Most "Only Corvette Owners Understand" Quirks and Problems
Pouria Savadkouei
10 Reasons the C6 Z06 is Still A Performance Benchmark After 20 Years
Joe Kucinski
How Much Horsepower Every Corvette Engine "LOST" in 1972
Joe Kucinski
Top 10 DOs and DON'Ts for Protecting Your Convertible Top!
Michael S. Palmer
Top 10 Most Explosive Corvettes Ever Made: Power-to-Weight Ratio Ranked!
Joe Kucinski
150 hp to 1,250 hp: Every Corvette Generation Compared by the Specs That Matter
Joe Kucinski
8 Coolest Corvette Pace Cars (and Replicas) of All Time
Verdad Gallardo
Thread Starter
Safety Car
Joined: Feb 1999
Posts: 4,043
Likes: 342
From: Central NJ
Re: Problem-rear end- HELP PLEASE (SmokedTires)
I second both the fluid/additive and bushing suggestions. May also want to consider side yoke end-play if the lubricant or bushing are not the problem.
:iagree: Could be the posi clutches sticking and releasing, the additive will help this. Also grab you rear tires at 3 & 9 o'clock and 6 and 12 o'clock and see if there is any play with either direction. Check the front of the trailing arms also to be sure the bushings/ shims are there keeping everything in place as they should.
Good luck :)
:iagree: Could be the posi clutches sticking and releasing, the additive will help this. Also grab you rear tires at 3 & 9 o'clock and 6 and 12 o'clock and see if there is any play with either direction. Check the front of the trailing arms also to be sure the bushings/ shims are there keeping everything in place as they should.
Good luck :)
