Found oil on the underside of the oil pan yesterday. Did an oil change and all I got out was 4 quarts. Never had any problems with oil leaks before. I check levels about once a week when I first got my burb a couple summers ago then about once month. No issues until yesterday. AFM was my first suspicion but wasn't sure if I ever read anywhere that the underside of the oil pan is where the oil ends up if you have lifter issues associated with the AFM. So where does the oil end up?

I've got 146k on my '08 LTZ. Does it seem odd that AFM issues would develop at this late stage? TSB mentioned something around 40-60k, IIRC.

 

If you are having AFM issues, you will be burning the oil and it will be coming out the tailpipe. I really doubt that is your issue here.

 

Of course not. That would be too easy...

Thanks for the reply.

 

you mite have a rear main leak

 

Anyone know what the "book time" is for a main seal replacement or replacing the rear crankshaft pilot bore? Apparently a porous crankshaft pilot bore can mimic rear main seal leak. I found a website that estimates national repair costs but can only find info on main seals....around $1000. I have a call into the dealer and they are looking into it but after a couple call backs, still nothing so not holding my breath.

Thanks in advanced.

 

Per all data for the 5.3L on a 2007

Labor Information l Mfg. Warranty Standard
Crankshaft Main Bearing
Replace
Main & Rod Bearings
Includes: Check All Bearing Clearances.
15.1 22.2
Main Bearings Only
Includes: Check All Bearing Clearances.
14.4 20.1