Jet Pilot, I have been running Castrol Syntec Dexron III, as that is what Bill K recommended at the time I had my VB and TC installed, one thing you need to be aware of is that DC says that using Castrol Syntec is a no no, if you have questions I would call Bill K's shop and get his recommendation. You will be very impressed with Bill's product.
------------------
00, 4x4,ISB,Quad Cab,LWB,Bed Rug,Smitty Built Side Rails, Century Canopy,Westach Combo Gauge, Bill K's VB,TC