On my 4L60E, I have developed a leak at the gasket between the tailshaft housing and the main body of the trans housing. No other problems that I can see.

My question is, if I replace just that gasket, is that sufficient? Is there an internal seal on the output shaft between the main housing and the tailshaft housing that might be contributing to this?

I was told once by a shop that the trans on my Blazer has a seal inside and if it goes, too much fluid goes into the tailshaft housing causing problems.

I am trying to identify the parts before I take this apart. Anything else I should look for? The seal at the rear of the tailshaft housing is fine.

 

Update - According to the service manuals, there is an O-ring type seal between the main body and the tail shaft housing. There doesn't appear to be any other seals that could contribute to a leak at this seam. Can anyone confirm this for me?

 

I believe that's all it is, there's no gasket just an oring.

 

Thanks. I replaced the O-ring and it worked. Leak stopped. The hardest part was getting the speedometer sensor in just right so it didn't drag on the reluctor gear.

Here is a tip for anybody who removed the speed sensor. Make sure you rotate the rear wheel and listen to the tail housing on the A4 transmission before you drive it. If it is rubbing, you will hear it and will need to rotate the sensor a little until it stops.

Also, it was so easy to remove the housing extension that if you ever have any difficulty removing the speed sensor, I recommend removing the extension housing and just pushing the sensor out by hand from the inside. This is a lot safer than trying to grab a stuck speed sensor with pliers possibly causing damage.

Thanks Kevin Blown 95 TA for confirming....