Hey guys, I just found a soft ball size puddle underneath my Cobalt. It looks like it's the rear main seal. I was wondering if anybody has used the Blue Devil rear main sealer on their Cobalts or any other car? Somebody said that it won't work on the cobalt, but I didn't quite understand what he was saying. Thanks in advance for any advice!

 

By the way, yes I know it's a cheap fix, but I know Blue Devil works really well on head gaskets. They say it's a "permanent fix." I just don't have the money to pay somebody to fix it right now.

 

Those type of sealers never work.

That much oil seems to be a lot for a rear main, but it's possible. It just started leaking? Maybe it's possible it's something less invasive? I don't see a lot of rear main leaks on ecotecs, even with very high mileage and poor oil change history.

 

It does seem very strange. All of a sudden I just saw the oil out of nowhere. I have been very diligent about my oil changes. I use Mobil 1 and I change it every 2,500 miles.

 

Here is a few pictures of the leak. To the left is the transmission pan. You are looking toward the driver side between the transmission and oil pan. I looked up top and found no leaks. Valve cover looks good, head, and oil sensor looks clean. That's all I can see. So I'm assuming its the rear main.

 

A rear main will almost always leak straight out the bottom, there's a small vent in the bottom of the trans that allows any liquid to run down, no reason for it to go out the rear at the level of the oil pan.

If you don't have a valve cover or rear cam seal leaking, i'd assume it might be leaking around the oil pan but that would also be the first time i've ever seen that on an ecotec that hasn't been opened up by someone and not resealed properly.

I'd still plan on just fixing it right or not at all. There is no good additive you can use on a sliding seal that will work.

 

Have you checked the oil filter cap?

 

Yes. It does not seem to be coming from anywhere visible from the top of the engine unfortunately. The oil path I am seeing is between the transmission and oil pan as shown in the pictures above. Besides that, I cannot see any other path.