Recommended Pan Plug Seal
 

I've had an oil leak for some time now, so I changed my oil a few days ago and found that the pan plug had somehow worked it's way loose. Not so loose to fall out but loose enough to leak. The only reason I can think this would occur would be a damaged or incorrect sealing washer.
The last time I changed the oil I used an aluminum crush washer, so I figured I'd try a different material. This time I installed a nylon washer and it didn't leak a drop for three days.
I backed the truck out today and I noticed oil on the floor. When I checked the pan plug, it was loose again.
Now I'm not sure what material sealing washer I should use.

In both cases the plug was tightened properly.

Any recommendations will be appreciated.

Re: Recommended Pan Plug Seal
 

Nylon is original equipment AFAIK. Maybe the threads are worn on the plug or in the pan?

Re: Recommended Pan Plug Seal
 

Yea, I'm pretty sure it's the original pan plug. Maybe it's time for an oversize plug.

Re: Recommended Pan Plug Seal
 

Maybe a oversize plug or try a copper crush washer first?

Link: https://orv.livejournal.com/327244.h...d-tight%20seal.

Re: Recommended Pan Plug Seal
 

I use a relatively thick cardboard style washer, works for me just fine without any issues. I think it may be about 3/32 thick

Re: Recommended Pan Plug Seal
 

Been happy with these.
https://shop.advanceautoparts.com/p/...B&gclsrc=aw.ds

Re: Recommended Pan Plug Seal
 

That thing should never come loose on its own. You have some type of issue, maybe even a metric bolt. I use a copper washer now due in part to the nylon one being 50 years old, neither loosens on its own.

Re: Recommended Pan Plug Seal
 

The plug didn't come loose if it was tight in the first place. You evidently forgot to tighten it, happens to best of us.

Re: Recommended Pan Plug Seal
 

That's the style I use. I have two vehicles that I installed different crate motors in and both came with the metal/rubber seals. Mine don't leak.

Re: Recommended Pan Plug Seal
 

If you read my original post, you'll see that it absolutely loosened, not once but twice.

Re: Recommended Pan Plug Seal
 

Maybe somebody else is messing with it then. we had an idiot at the dealership about 25 years ago that was trying to get the lube guy fired b'cuz he didn't like him and was pulling that ****. Lube guy was on though and got him fired and luckily there were not any customer cars that got damaged.

Re: Recommended Pan Plug Seal
 

Not a chance.
This truck has never spent a single night outside since I took ownership of it in 1999. And, although I drive it every day (Except when it rains) It's never left out of my sight. I consider it "The vehicle I drive when I have absolutely no where to go".

Since it's the original pan plug and I have changed the oil every 3000 miles (Tightened the plug EVERY time) since I have owned it, I'm thinking the plug is probably ready for a 1st oversize.

Re: Recommended Pan Plug Seal
 

I changed oil for 20 years at two different dealerships. I have removed and installed more drain plugs than most people on this planet. If the threads are good a plug does not come loose on it's own no matter what gasket it has.
ETA, if the threads are bad it won't tighten in the first place.

Re: Recommended Pan Plug Seal
 

https://paceperformance.com/i-648519...ain-plugs.html

or buy from your local GM dealer. These seal better IMHO than the stock ones.

Re: Recommended Pan Plug Seal
 

I fixed mine by using a flat washer and O ring. The washer has an ID slightly bigger than the O ring OD and is about .015" thinner than the O ring. I've done this on a couple engines and have never had a leak.

Re: Recommended Pan Plug Seal
 

Thanks for the link. I ordered a few.