Z28WannaB

I've got a 1995 Formula V8. I recently just replaced the intake manifold gaskets because it was leaking.

However, I am still leaking oil. I noticed there is a lot of oil on the back of my oil pan.

I think it is the rear main seal that is causing issues. Anyone know where it is located. How difficult is it to replace?

http://shbox.com/1/rear_main.jpg

- Z28WannaB

944v8inDFW

May be worth a cheap UV dye kit to help pinpoint the leak. About $20 at the chain stores. You might take a look at you oil pressure sending unit as well. Just my 2 pennies.

sssalah

This is the rear main seal and its housing. Its located between the engine and trany, you'll have to remove the trany and the flex plate to get to it. It could also be from the oil pan gasket, and that requires liftling the engine 3-4" up. Leave it to the next rebuilt if the leak is not that major.

Z28WannaB

The Oil pressure sending unit can leak?

You know, I figured it was just like all the other f-body guages and was innacurate. But maybe you know.

My fuel pressure gauge, is kinda spuratic. It obviously goes up and down as you apply more gas and let off. But it kinda twitches noticably.

Is that anything to be concerned about? Could my sending unit be going out?

Back to the main rear seal, anyone know how to locate it? And is it difficult to change?

- Z28WannaB

multicar

Like sssalah said, it's behind the flexplate/flywheel. Its known as a 1piece rear main seal. Most don't go bad, unless blowby is excessive and blows them out of the retainer. If you go there,, you need the seal and the retainer gasket.
Doug

TW95Z

Here's a link to my write up when I fixed my leak. I had to replace the oil pan gasket because it was leaking also. These pictures will look familiar once you get the tranny out and flexplate off.

http://www.pharmacy.arizona.edu/staf...RMainSeal.html

Good luck,

Kevin Jackson

Did you fix the intake yourself? I dont mean to doubt your abilities, but there is a good chance it is still your intake. Back when I had an LT1 i did the fix myself, and used a nice thick bead of sealant, put on the manifold perfectly straight, and everything else by the book(or DIY guides from here). well shortly after it started leaking agian and worse. I thought it was a sending unit or rear main so I took it to a shop and it turned out to be the intake again. the mechanic said even though i used the right amount of sealant according to the books, that you need to use alot more, almost an excesive amount. he said he used an entire tube for the front and rear seals.

DarkHorse

You don't need to raise the engine to replace the oil pan gasket. Just drop the pan and stretch the gasket over the pan, it's actually quite an easy job and fast too.

97WS6SCharged

You still have to raise the engine a little bit to get the pan off of the front two studs that GM used on the LT1. What a pain.

Lt1t56

How long ago did you reseal the intake ? did you clean old oil off trans and engine ? Just wanted to mention this because if you have had an intake leak for a while there is going to be a lot of residual oil still dripping off engine and trans, mostly when engine is warm.

DarkHorse

?

Not on my car you don't. I just had mine on and off last night before an event today. Not sure if yours is different but I have 2 studs in the rear and my fronts are 12mm bolts vs the 10mm bolts along the sides. I don't have to jack squat up to lower my pan and replace the gasket.

97WS6SCharged

Hmm... GM must have changed them somewhere over the years. The three LT1's I have all have studs on the front and back two holes for the oil pan.

DarkHorse

That's weird. Are the front 2 different sizes from the rest? Mine are 12mm or 1/2" I thought that was very odd.

97WS6SCharged

Yeah, they use a 1/2" nut with the studs. The rest of the pan bolts are 3/8".