Okay, so I bought this Suburban and thought it was/is a nice truck for work. I have had many issues though lately with the truck and I now have a new issue. After a no start was cured with a new PMD I now have oil leaking out through the bell housing... Assumed it was the rear main seal and went through the process (which was a mission for me to do) of removing the 4L80e to replace the seal. I was so excited after I reinstalled the tranny thinking I would finally have my truck on the road again, but to my disappointment IT STILL LEAKS!!! I noticed the oil pressure is at 70 or higher and am thinking/hoping it is something simple. Any ideas are appreciated. Thanks guys...

Check your CDR if it drity it make rear main leak

take the CDR off and clean with brake cleaner or gas just make sure it dry before putting back on

not sure why oil that hight for maybe the guage going bad

The pan seal will also leak. I have seen a rear main seal failure diagnosed, when it was actually the pan leaking. Resealing the pan is much easier. But do check CDR function before going any further.

Jake

also look at the valley to see if it might be coming from somewhere else and just looking like it's from the rear. i assume it's not atf, right?

No, not ATF. Also, did the water test (for CDR) on the dipstick tube, no bubbles... water did come up into the clear tubing. Oil pressure is higher than normal (sitting at idle @65-70). Checked valley and saw nothing that looked suspicious.

Clean the area and "watch" for the leak .There are fluorescent dyes you can add the the crankcase to help find the leak.

Check the oil pressure switch (OPS) its behind the fuel filter, could be leaking at the fitting, and running down.

clean the CDR very well and see if leaks continue

I think your OPS is under the intake manifold on a '96, if it is leaking it will leak into the valley under the manifold. The valley has a drain tube from the valley to the drivers side of the block around where the oilcooler lines exit the block this could be missleading and look like it is coming from the bellhousing, by the way most auto trans equipped blocks don't have this tube it is mostly found on manual trans vehicles so oil and fuel doesn't make its way onto the clutch, I guess GM didn't care if it went all over the torque converter as it wouldn't cause any harm other than a big mess the converter can sling around inside the bellhousing and then leak onto the ground. A fuel leak can also appear as an oil leak when it washes the grease and dirt loose from the valley and it may look like an oil leak, put your finger in the puddle and smell it and see if it smells like fuel, that will head you in the right direction. If it smells like fuel check your fuel filter housing, it has o rings in it for the fuel heater and water in fuel sensor. Good luck and keep us posted with your findings.

Saw this thread before I saw your other thread with the PIC of the crack in your block. Check your other post.

Thanks to all who commented. I've started a new thread as I discovered (with your help) where the oil was coming from. Turned out to be a crack in the OPS mount location. Poor engineering on GM's part if you ask me, should have mounted flush into the block and not on a rise as shown in pics. In any case I am now faced with a new problem, how to repair/salvage 6.5 block due to this small crack. Thanks to all who replied!!!!!

do not use brake clean to clean CDR it will disform rubber gaskets use diesel or gas

Took some pic's to share... see them on FB Here, http://www.facebook.com/album.php?aid=2034809&id=1317256731&l=55387d3c2c