This is the fifth time that I've had to have the left side cover on the diff replaced. Everytime we follow all the directions and it lasts around 3500 miles and starts all over again. Last time, they installed an new side cover, seal and axle. It lasted almost 3200 miles and starting leaking last night. No racing, just normal driving. HELP ANYONE. By the way, its a 2000 coupe a4. 19450 miles

 

Maybe the bearings inside are shot. Is there any play in the half shafts?

 

Whatever you are doing-----STOP IT!

 

The cause of the leak is rubber seal failure! You need to figure out what is causing the seal to fail. Most likely lateral movement of the output shaft! Insist the deler check for lateral play. You can check it your self. Crawl under the car and try to move the output shaft forward and rearward and up and down. If it is excessive, something is worn inside!!

Keep us informed on the results.

BC

 

Are they using the latest design axle and cover seals? GM had a lot of problems with the older design axle seal and especially the differential cover seal. There was a service bulletin that came out on this around the 1st part of November 2003. Have your service people look it up and make sure they're using the latest redesigned seals. The service bulletin lists the P/Ns of the redesigned seals. Good luck.

 

Next Monday my 2003 MN6 goes in for the fourth time. I have heard that the 03 and 04's have the new designed seals in them from the facorty. Can any one prove that myth true or false. I have 21K on my car. It is a daily driver.

 

Just dropped off my 04 A4 (12,000 miles) tonight for the leaky rear end.

First time I've ever had it back to the dealer for service.

 

I don't know this for certain, but as I remember from an article that I read on this in the past, GM for whatever reason elected not to introduce the redesigned seals in the transaxle build process for model years 2003 and 2004. Our car was a later build 2003 model with a build date of March 24, 2003 and the tech found the old seals in it. I've seen a few posts here in the past where several 2004 owner reportedly said their cars too were found to have to old seals.

It's been a while since I read the article and I don't remember the details now on the axle seal. As for the differential cover seal though (which is an O-ring), the article as I remember said that the cover seals were somewhat too small in diameter for the grove in the differential cover. As a result, a proper seal was not always formed between the cover and differential carrier mating surfaces. My understanding is that the newly designed cover seal is much thicker. The tech that replaced mine said there was no mistaking the new cover seal in that you nearly had to pound it into the grove where the old one would fall right into place. The mating surface of my left side differential cover was also scored and this was replaced too along with new axle and cover seals.

I believe it was CF member C-5 Tech that submitted an excellent post quite some while back on the November 2003 Service Bulletin and the exact procedure that should be followed for this repair and the replacement of the seals. From his post he was obviously very familiar with this. I have looked a number of times and can't find his post. I'll bookmark it if I ever find it again.

 

I have heard of and seen a lot of '04s in the shop for the seal repair ...not looking foward to it happening to my '04