96 Burb Oil Leaking Rear Main?

[lincoln20012002]

Ok, I have searched this forum fairly well on oil leaks and I need some advice.

I have a 96 k1500 5.7 suburban, with an oil leak from the rear of the engine.

Currently the trans is OUT of the truck and off getting rebuilt, while out I thought it would be a great time to look at the oil leak problem. It looks like I have two leaks,
1 is the oil filter adapter and the cooler lines that go to it.

The second leak looks like the REAR Main seal. From what I have read it is fairly uncommon for the late model rear main to leak.

Should I drop the pan and do a rear main and oil pan gasket while the tranny is out or does it sound like I have another problem?

The only reason I hesitate is the Chilton manual makes the oil pan removal sound like a bear. ie, "remove the two upper right side front axle mounting bolts and rotate the front drive axle with the front wheels turned to the left" From looking underneath Im sure how that is going to work......help!

[2000CAYukon]

Is the flex plate off so you can see that the rear main is really the source of the leak? It is more common for the rear of the intake to be the source of the leak.

If you decide to do the rear seal, use a cherry picker to lift the engine up high enough to remove the oil pan. Since the tranny is out, it will be easier than if it was in.

//2000CAYukon

[lincoln20012002]

I need to take the flex plate off, but I can see the rear main through one of the holes and I can see oily residue from the rear main area.


If the the intake was leaking oil down the back side of the engine, is it known to run down and collect in the torque converter cover?

Before I pulled the trans, I noticed engine oil dripping from the torque converter cover, almost like the rear main was leaking and running down into the cover.

[2000CAYukon]

Originally Posted by lincoln20012002

If the the intake was leaking oil down the back side of the engine, is it known to run down and collect in the torque converter cover?

Yes.

//2000CAYukon

[lincoln20012002]

Ok, tonight I will remove the flex plate to make sure its not the rear main and also, I am going to look very closely at the back of the intake.

I guess I never thought of the intake being able to leak oil like that, but from what everyone posts on this forum I would say its 10 to 1 in favor of a leaking intake and not the rear main.

I will let you know what I find.

Thanks for the advice, its really nice to get some good input before starting a major operation.

[lincoln20012002]

With the flexplate off and the truck up on the big jack stands, I can see that the rear of the intake is leaking oil. It must be a fairly decent leak as I can see it has been running down the back of both heads and all over the bell housing of the trans. It also has been leaking into the torque converter cover, it really makes sense now that I know what im looking for. I think that all of the oily residue that i am seeing on the oil pan and around the rear main is from the rear of the intake. I guess when the burb is running and driving down the road it must really sling oil out of there and run all over everything.

While the intake is no small job, I am more comfortable doing that than the rear main. (lots of documentation on this site!)

Thanks 2000CAYukon for your advice, I really think you saved me from a lot of unneeded work.

I know what Im doing this weekend

[2000CAYukon]

In case you have not seen the DIY thread on replacing the intake gaskets, here it is http://www.automotiveforums.com/vbul...17#post2613117

The Fel-pro gaskets are the updated design and work very well.

Glad you figured it out!

//2000CAYukon