Thomastp

This is a recap of what I did to solve a real bad oil leak(s) on my new to me 94 LT1 6 speed coupe with 85000 miles.

After all the advice I received on the forum I did a lot of investigation and determined that I would replace the rear main seal and the oil pan gasket. Once I had the transmission out and the flywheel off I could see how bad the rear of the oil pan was leaking. There was also a lot of oil on the front of the oil pan and cross member. I couldn’t determine if this was a result of a leak in the oil pan gasket or somewhere higher up on the timing cover. The rear main didn’t look too bad but since I had purchased the new GM seal, with the flywheel off, it’s a 5 minute operation to replace it. The clutch wasn’t slipping and it had plenty of wear left on the disc, so I just reinstalled it (Now I know what a dual mass flywheel is). I finished up last night. I started the car and checked for leaks. Nothing. I did an around the block run and nothing. I went for a 20 mile highway run and the oil pan, bell housing, and starter were dry. But, I did have a leak. It looks like the seal on the tail shaft of the 6 speed is leaking. This is a new leak. Oh well, off comes the exhaust system again. At least I put the exhaust system on with all stainless nuts and bolts. It sure is nice to have the under side of the engine dry.

I do have a couple of questions. I used the Felpro “blue” gasket on the oil pan. When I filled the engine with oil, the level didn’t even come close to the upper limit on the dip stick. I put in 4.5 quarts. I added another ½ quart and it’s now closer but still not there. I’m thinking that the Felpro was much thicker than the original gasket so that caused the level to be low with the specified 4.5 quarts. With that said I should put in enough oil to get the level to the upper limit on the stick. The upper level on the stick would be where the oil level needs to be in the pan to cover the pump. Has anyone experienced this with using the Felpro “Blue” oil pan gasket?

I used the BMW/ Castrol 5w 60 synthetic in the transmission and it seems quieter. Has anyone had the same result?

My next chore will be to replace the clutch hydraulics because I have a hard shifting condition at times and after reading all the information the ZFDoc has on his site it sounds like my problem is the clutch actuator cylinder has developed a hang up spot between the seal and the bore at the fully extended end of the cylinder’s travel range. I will post an update with the results after I do the repair.

Well, thanks to all for the input. The transmission removal wasn’t too bad and it will be much easier the next time I have to do it.

Southern Comfort

I also used the Felpro blue and I had the same problem. 4.5 quarts dosent do it and 5 barely does. So with your situation and mine I have to believe that the additional 1/4 inch of the gasket is the problem.

But....no leak either... :party:


[Modified by Southern Comfort, 7:45 AM 10/8/2003]

YLO Z06

Congrats on your repairs!! :cool: I, unfortunately, am still suffering from a front oil pan gasket leak (even after 3 new gaskets). A question -- where did you put RTV sealant for the oil pan gasket?? I did not put any where the gasket meets the timing cover (per the GM manual), and that is where my leak is. I think I will seal this area next time...

Thomastp

I didn't use any sealant per the Felpro instructions. I made sure that everything was supper clean. One area that needed a lot of attention was the bottom of the timing cover. The original gasket left little ribs along the surface and because of a the space restriction I used a small flat blade screw driver to remove them. Then I used a scotch brite pad to clean off any remaining junk. After that I cleaned the block and timing cover areas with a rag and brakekleen. I think that even any sealant might cause a problem. That Felpro has bushings in the corners so its imparative that there is nothing under those corners to hold up the bushing. Hope this helps.