Tremec TKO 600 Oil

[ceslaw]

Need to confirm the proper lubricant for a TKO 600. The specs call for GM Syncromesh #12345349 or Dexron III / Mercon Spec ATF. Bought a bottle of Penzoil Syncromesh and a bottle of Dexron III. Both are red in color. The fluid that was supplied by Tremec is green and really stinks. I don't want to mix different types of fluid if it will cause a problem. So I have the following questions:

1. What was supplied by Tremec? Why is it green and why does it stink, compared to the recommended fluids noted above?

2. Is the red Dexron III and the Penzil Syncromesh (which lists the GM part number specified by Tremec) compatible with the green stinky stuff?

3. The fluid suppled by Tremec comes in a plain black bottle with a nondescript label, but it does describe the fluid as "synthetic." Is the Dexron and Penzoil/GM Syncromesh fluid a synthetic? If not, could this be the difference between the green and red colors and the pungent aroma?

I only need to add a few ounces to top it off (to replace a bit that drained out the rear end when I removed the transmission to do some flywheel / clutch work).

CESLAW