Leaking Differential ----NOT GM's PROBLEM
Thread Starter
7th Gear
Joined: Nov 2004
Posts: 7
Likes: 0
From: Sweetwater TN
Leaking Differential ----NOT GM's PROBLEM
2004 6 speed coupe, 18,000 miles
Rear differential left side still leaking after FOUR repairs.
4/05 6,883mi replaced seal
5/05 7,069mi replaced seal
11/05 11,541 mi replaced seal
8/06 14,406 mi new side cover and seal
Differential still leaking. Car out of warranty, so its my problem.
GM doesn't even warranty it's own repairs.
How many times does it take a GM mechanic to actually do a repair correctly????????????
NO WONDER TOYOTA IS NOW NUMBER ONE
Rear differential left side still leaking after FOUR repairs.
4/05 6,883mi replaced seal
5/05 7,069mi replaced seal
11/05 11,541 mi replaced seal
8/06 14,406 mi new side cover and seal
Differential still leaking. Car out of warranty, so its my problem.
GM doesn't even warranty it's own repairs.
How many times does it take a GM mechanic to actually do a repair correctly????????????
NO WONDER TOYOTA IS NOW NUMBER ONE
Le Mans Master
Joined: May 2006
Posts: 7,871
Likes: 252
From: Hillsboro OR
Try this number....
The independant Fleet Manager that I bought my car from gave me this number (1-800-222-1020) . It is supposed to be the GM National Customer Service line. I never called it because I convinced the dealer to solve the problem I was having. Good Luck. 
Team Owner
Joined: Jul 2004
Posts: 124,407
Likes: 288
From: .... NJ
Cruise-In VII Veteran
St. Jude Donor '05 thru '19
I just called for an appointment, my warranty expires on 7/26. I had the seal and cover replaced last year. When I changed my oil back in May I noticed the rear spring on that side had oil on it and the area around the cover on the left side was wet again.
I bet a lot of people who never inspected the rear and know to look for this issue get it fixed. It is a slow leak so I never really saw oil on the floor in the garage.
I bet a lot of people who never inspected the rear and know to look for this issue get it fixed. It is a slow leak so I never really saw oil on the floor in the garage.
Burning Brakes
Joined: Apr 2004
Posts: 908
Likes: 0
From: Ponchatoula la.
2004 6 speed coupe, 18,000 miles
Rear differential left side still leaking after FOUR repairs.
4/05 6,883mi replaced seal
5/05 7,069mi replaced seal
11/05 11,541 mi replaced seal
8/06 14,406 mi new side cover and seal
Differential still leaking. Car out of warranty, so its my problem.
GM doesn't even warranty it's own repairs.
How many times does it take a GM mechanic to actually do a repair correctly????????????
NO WONDER TOYOTA IS NOW NUMBER ONE
Rear differential left side still leaking after FOUR repairs.
4/05 6,883mi replaced seal
5/05 7,069mi replaced seal
11/05 11,541 mi replaced seal
8/06 14,406 mi new side cover and seal
Differential still leaking. Car out of warranty, so its my problem.
GM doesn't even warranty it's own repairs.
How many times does it take a GM mechanic to actually do a repair correctly????????????
NO WONDER TOYOTA IS NOW NUMBER ONE
Drifting
Joined: Apr 2005
Posts: 1,753
Likes: 29
From: McKinney TX
Does anyone know exactly what the problem is? I have read about people having this problem many times.
I have an 02 and have never seen leaking diff fluid. Was this problem mainly on 03+ year cars? How can you tell if your butt is leaking if it doesnt leave a puddle?
I have an 02 and have never seen leaking diff fluid. Was this problem mainly on 03+ year cars? How can you tell if your butt is leaking if it doesnt leave a puddle?
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Racer
Joined: Jun 2004
Posts: 321
Likes: 0
From: Bethlehem PA
St. Jude Donor '08
Before everyone starts bashing GM, your repair will be covered under the GM good will policy. Especially with previous repair attempts. It is the dealership service manager who is saying no. Insist that he call in the claim to GM for approval or go to another dealership that will. If the service manager refuses, then call 1-800-222-1020 and open a complaint against the dealership. Just be nice until it's time not to be nice! Good luck
Racer
Joined: Jan 2007
Posts: 409
Likes: 1
From: Warrington Cheshire, England
Before everyone starts bashing GM, your repair will be covered under the GM good will policy. Especially with previous repair attempts. It is the dealership service manager who is saying no. Insist that he call in the claim to GM for approval or go to another dealership that will. If the service manager refuses, then call 1-800-222-1020 and open a complaint against the dealership. Just be nice until it's time not to be nice! Good luck
,
Hi there,
I have a 2004 CE.
I can't see any leak on the diff, but there is a dark stain, which might have been a previous.
If it is leaking, would it be covered bu GM good will policy in UK? or just USA?
Just what is the problem, what does it stem from. i
is it poor materials, or poor workmanship?
Drifting
Joined: May 2003
Posts: 1,755
Likes: 97
From: Sandy Utah
Had the same problem twice. Second time fix over three years ago and so far, no problems. The first fix was with the same seal as was in the car when it was new. The second fix was with a new seal that was developed to fix this problem. Look at the repair invoices and see if they use seal nbrs 88996703 (I beleive this is the axle O-ring) and 89047953 (left side cover O-ring). These are the new parts as 14 July 04 and fixed my leak. Good Luck. My car is a 2001. 
Race Director
Joined: Apr 2004
Posts: 16,135
Likes: 5
From: Newberry FL
Cruise-In VIII Veteran
St. Jude Donor '07
I would try the customer service manager and let him have an ear full. I am certain that GM will do the repairs if it hasn't been very long since the last fix, you just need to talk to the right person.
Melting Slicks
Joined: Dec 2004
Posts: 3,049
Likes: 0
From: The second childhood is the best one of all.
2004 6 speed coupe, 18,000 miles
Rear differential left side still leaking after FOUR repairs.
4/05 6,883mi replaced seal
5/05 7,069mi replaced seal
11/05 11,541 mi replaced seal
8/06 14,406 mi new side cover and seal
Differential still leaking. Car out of warranty, so its my problem.
GM doesn't even warranty it's own repairs.
How many times does it take a GM mechanic to actually do a repair correctly????????????
NO WONDER TOYOTA IS NOW NUMBER ONE
Rear differential left side still leaking after FOUR repairs.
4/05 6,883mi replaced seal
5/05 7,069mi replaced seal
11/05 11,541 mi replaced seal
8/06 14,406 mi new side cover and seal
Differential still leaking. Car out of warranty, so its my problem.
GM doesn't even warranty it's own repairs.
How many times does it take a GM mechanic to actually do a repair correctly????????????
NO WONDER TOYOTA IS NOW NUMBER ONE
Race Director
Joined: Apr 2004
Posts: 16,135
Likes: 5
From: Newberry FL
Cruise-In VIII Veteran
St. Jude Donor '07
I know you want to vent at GM but this is really a reflection on your dealer. GM dealers are given the discresion to make repairs in your situation and bill GM. Just today I got a $1200 replacement job on my traction control module for $300. My car is an 2002 with 23000 miles. Last year my dealer replaced my diff cover and seal for free. It was out of warranty for 19 months. I would recommend you find a dealer with a service department manager you can build a relationship with. Many service dept. managers are just mechanics and not very consumer oriented. The one I go to is very consumer oriented. Remember you can catch more bees with honey than vinager. It seems you may have ticked him (or her) off.
Nicely put.
Last edited by mph1972; Jul 19, 2007 at 09:50 PM.
Instructor
Joined: Aug 2004
Posts: 118
Likes: 0
From: Waukesha Wisconsin
I know you want to vent at GM but this is really a reflection on your dealer. GM dealers are given the discresion to make repairs in your situation and bill GM. Just today I got a $1200 replacement job on my traction control module for $300. My car is an 2002 with 23000 miles. Last year my dealer replaced my diff cover and seal for free. It was out of warranty for 19 months. I would recommend you find a dealer with a service department manager you can build a relationship with. Many service dept. managers are just mechanics and not very consumer oriented. The one I go to is very consumer oriented. Remember you can catch more bees with honey than vinager. It seems you may have ticked him (or her) off.
Advanced
Joined: Feb 2005
Posts: 50
Likes: 0
Had mine done 5 times and last year it started leaking again. I drained it and the filled it with Red Line and knock on wood, it stopped and hasn't leaked since. Red line states it lowers the temperature by 6 to 7 degrees and I wonder if thats what it takes to reduce the pressure inside. Don't know for sure, but so far so good.
Race Director
Joined: Jan 2002
Posts: 19,557
Likes: 1,470
From: I love you & miss you Linda
2017 C7 of the Year Finalist
St. Jude Contributor
If you lived in PA, you'd be in a new car by now.
They get 3 strikes here and their out.
The silver Z06 in the picture below behind my EB 02 is a prime example...
They get 3 strikes here and their out.
The silver Z06 in the picture below behind my EB 02 is a prime example...