Hey Duramaster!!!!!!

[Diesel_D]

It looks as if my coolant leak is the oil cooler. You said you were changing one this week, are there any tricks or is this pretty straight forward? When i pull off the cooler am i gonna lose all my antifreeze? IM assuming the gasket is a dealer part? Any advice would be appreciated.

[mafrazer1]

oil cooler is connected to coolant system, so you will lose some when you break it loose. Oil too of course.(I don't know how much)

There is no gasket at the block face, it is 2 o-rings, one on the face, one on the boss that fits in the 28mm hole. Save them and check for damage.
Also check block face surface for roughness where o-ring mounts on face.
Any rough surface should be smoothed over to get good seal.

I manage tools and programs on the CNC machining line that cuts this area of the block. There have been some leaks reported due to poor finish on this face where o-ring fits. In 2002 I changed the machining process to improve surface spec. on this face at the request of Mfg.Engineering.
No reports of leaks since then.(none that got all the way back to me)

[Duramaster]

WOW! That's one way to get my attention! Yes, there are two O rings at the blosk face. There is also a O ring where the pipe feeds into the cooler from the front and a gasket where the pipe attaches to the waterpump. There is also a gasket where the aluminum "ELBOW" attaches to the rear of the cooler and then a goofy rubber gasket where the elbow attaches to the rear engine bellhousing adapter/ cover. I added about 5 gallons of coolant/ water mix to the engine (50/ 50 of course). Oil loss was only about a quart at the most. It is an ugly job that requires some assistance upon reassembly and I also made up a few new WORDS! :p It takes alot of patience! There was also an update a few years ago stating to add a thin application of GM Assembly adhesive at the O ring block surface to prevent future leaks.

Lot's of luck and have fun with the expanded vocabulary!!! :D:D

[Diesel_D]

I just wanted to see if you were paying attention. Thanks for all the help.