95 GC V8 oil leak near filter

[The_Penguin]

Well my '95 doesn't want me to sell it. It decided to start leaking oil.
I first thought it was a defective filter, as the oil was leaking around the filter. Tighening it didn't help. So I replaced the filter, but no, still leaking.
I haven't crawled under it again yet, but I'll likely find it's still leaking around the filter.

I searched and read a few threads, and just wanted to ask again before I tackle it.

The seal on the filter adapter (O ring) is only on the 6cyl, correct?
If that's the case then I should probably look at the pressure sending unit? Anything else I should look for?

Thanks.

[hundahunta]

if I am not mistaken I think this year engine has a oil filter adapter housing,...

[The_Penguin]

There's nothing in the service manual that I can see. Under the filter I think there's a nut on the threaded shaft that the filter screws on to, but I doin't see what would leak, as it's all surrounded by the filter gasket.

[Cam7]

Cant see any thing in my manual. The only way I have found oil leaks is to clean the engine and crawl underneath and look. Oil leals are hard to find and mask where they are comming from. One time I thought i had a leak comming from the Valve Covers after wipping down the motor and crawling under the leak was comming from the intake manifold. Jack it up and crawl underneath.

[Myrtle Beach]

i had the same problem with my 4.7 and it turned out to be the pressure sending unit. I don't know if your motor has the pressure unit mounted above the filter but if it does it is a cheap fix. I would definately check to see where the pressure switch is mounted for your engine. Hope this helps.

[dksob81]

I had the same problem after I changed my filter and oil, I the O-Ring (gasket) on the oil filter got stuck on the engine when I removed the old one, and when I put the new one on the doubled up gasket caused it to leak.

[The_Penguin]

Well it just keeps getting better.
I crawled under there tonight, and the filter is clean and dry. Looks like last week's fix worked.
The new leak is coming down the back of the engine, and dripping off the bottom of the transmission housing. Trying to be optimistic, I located the oil pressure sending unit, between the EGR valve and the distributor using the braille method, and felt around. A bit of oil came back on my finger. So I wiped as much off as I could and went for a drive. Came back, and felt back there again, trying not to fry my hand.

Dry.
I think that spells rear main seal.

[dksob81]

yea if the leak is not coming from the Oil Pressure sending switch, then the rear main seal would be the next palce I would look. also have u checked the Oil Pan toward the tranny, the gasket could be bad, but if it is coming from inside the Tranny bell housing then it would be the REAR MAIN SEAL.

[Cam7]

If it is the rear main it shouldnt be too hard to fix. Pull the pan, oil pump and rear main bearing cap. the hard part is to take out the upper old seal and install the newer uper seal. Did one on a Chevy 350 lately wasnt too bad. Replaced one on a Geo Metro had to pull the motor.

[dksob81]

yea to get the upper seal off just use a Nail or Center Punch or something, and pound in on the one side of the seal so that it will slide out the other side then use some pliers to pull it out. and reverse to get ti back in. it is a lil tricky.

[xj31]

Yea, the seal is pretty easy to change-once you get the oil pan off.Good luck with that.Before I would go and start putting a rear main in it,I would check and make sure that the intake isn't leaking out the back.Trust me, you don't want to take that oil pan off if you don't have to.