Oil Leak Woes

[ballsie]

2002 Qx4 4x4 123k miles

Long story short....

I had a small (seep) oil leak at the valve cover. One of my customers is a GM dealer and they offered to replace the gaskets for $200. It was a no brainer so I let them do it. Well, they cracked one of the valve covers in the process and replaced it with an OEM Nissan valve cover.

Got the truck back and it had a major oil leak within 2 days of getting it home. Brought it back to the shop and they said it was the rear main. They offered me a great price to replace it, so I had them do the rear main, the upper oil pan and the lower oil pan gaskets along with a couple other unrelated items.

They ran the truck on the lift for a couple of hours after the work was completed and it had no leaks, but after a 20 mile test drive the truck is leaking oil just as bad as it did before. The shop then went to Infiniti and bought all new OEM gaskets and did the job all over again with the same results.

Now they are thinking it might be a head gasket. Does anyone have any info to offer? I think they are just grasping because the HG is just about the only gasket left to replace!

Thanks!

[ballsie]

Just to clarify, Oil is leaking between the motor and transmission.

[atraudes]

It sounds like the rear main seal. I've read a few stories here where people have had to have it replaced a few times before it's fixed properly. From what I gathered, that seal can be difficult to get set properly.

[ballsie]

Considering he pulled the entire truck part twice to redo the entire job, I would think he got it right.

I read a thread a little while ago from a guy with the axact same issue shortly after having his valve cover gaskets replaced.

The only leak I had was a seep at the valve cover gaskets. I let them swap the VC gaskets and all of a sudden I have a rear main leak less than a tank of gas later. I read that a loose valve cover bolt could run oil down the back of the motor and mimic a rear main between the motor and transmission. I have my fingers crossed with that idea!