lowercasee

So in the past few days, I have noticed a few rather large oil spots (~1 ft. diameter) in my driveway. Prior to that, it was dry outside of the few old spots from when the trans plugs were leaking. Upon looking underneath the truck, I saw that the front of the transmission, back of the motor and oil pan were covered in oil. Immediately thought it had to be either the oil pan gasket, or worse, the rear main seal. On further inspection though, the oil appears to be coming from up higher at the back of the valve cover. Most likely suspect for that, to me, is the cover gasket. This was recently replaced with a Felpro (as you can see in the pics) though so I am kind of surprised it's leaking again. Is there anything else it could be or do I just need to replace it again? Sorry for all the pics, just wanted you to see what I am seeing. Thanks!



Back of driver's side engine compartment, looking at trans


Passenger side rear, valve cover


Passenger side rear from underneath


Back of driver's side, valve cover


Passenger side underneath again


Back of passenger side rear valve cover again

Steve83

The oil on top of the VC lip makes me think it's coming out of the PCV grommet, the breather grommet, or the filler neck. Have you checked the torque on the VC bolts?

lowercasee

It's only at the back of the valve cover so I can't imagine it's the breather up front. There does appear to be oil on the grommet in the back and the plastic part in it seemed to be about half way out I pushed it back down but there was barely any resistance at all. Should it be a more snug fit? Could the grommet just need replaced?

BLDTruth

Does the pcv valve rattle when you shake it?

The grommet the valve sits in should be very snug.

lowercasee

I will give it a shake and see. It definitely is not tight at all. Just to confirm this is the grommet at the back of the valve cover, not the breather in front that goes to the air box.

lowercasee

Just checked and yes, when I pulled the piece out of the grommet and shook it, it rattled like there was a marble or something in it

Steve83

Yes, grommet 6K780 (lower Left pane of this diagram) should be very tight, and they're available new at most parts stores:


(phone app link)

If you pull it out of the VC, be careful not to tear it and drop the pieces into the crankcase.

lowercasee

Gotcha, thanks! Will probably pick up a new PCV valve as well just because. Will also make sure that the VC bolts aren't loose.

Edit. Would the loose PCV valve / leaky grommet really cause that much oil leakage? Also, any tips for getting it out safely? I could just try to pull it first and see if it's still got enough elasticity. Or maybe cut it and work it out.

sdmartin65

It's possible the PCV could leak that much. If it turns out to be the valve covers leaking the oem gaskets on my 95 are an oring impregnate into steel. They are a bit expensive new but a set from the wrecking yard would work perfect, they are very durable. I always use blue thread locker on the bolts.

lowercasee

Thanks for the tips, hopefully I can check it out this afternoon.