I just had a conversation with Corey Crump at Standard Transmission in Fort Worth. Standard has been in business for a many years and they set up at most all of our local swap meets. They are representatives for Hurst Performance and work on and carry a complete lines of transmissions and parts including the Tremac and all of the Borg Warner transmissions, including the T-5's we use.
I asked Corey what oil or grease they recommend as a lubricant for the T-5. He told me definitely ATF because the construction passages and tolerances are so close on the T-5 that oil of any weight will just not flow into these passages to lubricate the transmission. I questioned him about gear oil and he said "No!"
Everytime I get into this conversation, I always end up with the same answer and I would recommend that those of you who refuse to accept ATF as being correct for your T-5 rethink your approach to these transmissions and use what is recommended by the peole who build them, use them and rebuild them.
