bump...

Some of you put some miles on the t56 so far and i would like some more feedback with the original question

I know this is an older thread, but I thought I'd add the information I recently (Oct. '15) received from Tremec when I asked them the same question. The answer was Mobil 1 Synthetic ATF. In my question to Tremec (via the tech line on their webpage) I referenced the recommendations for Dextron III and Pennzoil Synchromesh and even asked if I should break in the T56 with the Dextron and then switch to something else or stay with the Dextron and Tremec clearly stated in its reply that " the correct fluid for your Magnum transmission is Mobil 1 Synthetic ATF".

Royal Purple Synchromax. Its purplish red and is like ATF. The bottle specifically says for use in T56s

IMHO, those guys at Tremec are yahoos and don't know anything other than how to write up a sales invoice. I called them a while back about bellhousing alignment and they told me its not required, but if I wanted to....following these directions (which were for the 4 speed bellhousing). Told him about removing the front plate and he proceeded to tell me not to take the transmission a part.

It really depends on who you happen to get connected to on the phone which varies day to day. I asked a similar question about alignment and the Tremec tech told me it was absolutely necessary to align the bellhousing and said the onl way to do it correctly was to remove the front cover. One would think you could get a straight answer on such basic questions.

I used some valvoline dex3. I have redline d4 ready to go in once i put 500 miles on the car and change all the fluids