New guy to the site, have had my 92 305 TBI for about 7 years now and have a very slow oil leak coming from the rear of the engine. Questions I have are: How much should it cost to have the seal replaced; How hard would it be for me to change on a lift in a military Auto Hobby Shop with a fair knowledge of cars and a very good knowledge of this one; Any other places I should be checking for this leak?

When the leak first started, I did the valve cover gaskets (hoping it would be that easy) but still had the same leak. As stated before, it is a very slow leak (only a couple of drops in the driveway after driving around). The leak isn't large enough yet to affect the oil level to the point of adding oil. Also, I have never had the oil pan off, should this also be something to look at?

I have heard that this engine is pretty notorious for RMS leaks just wanted to run it by the knowledge holders before proceeding.

-Rob

 

The 2 piece rear main seal was bad for leaks, the one piece unit was supposed to correct this problem. You have a 1 piece seal in your engine.

 

Thanks for the info... So this means I will be dropping the tranny huh? Any answers to the questions above?

 

Some other places to look for the leak are the oil pan gasket, oil pressure sending unit, back of the intake manifold, oil dipstick tube. If you are pretty sure it is the rear main seal, you could drop the inspection plate from the trans and clean it out real good up in there and keep an eye on it for leaks (put the cover back on before driving it)

 

unfortunately, you'll have to pull the tranny(and i believe the flywheel) to replace that seal it sucks...i had to get a new seal put in when the tranny got rebuilt