Hey guys was wondering if you could answer me some questions, I'm about to start a mark viii swap for my 2000 mustang gt. Was wondering if I need the t-45 or the tremac 3650 ?
Just wondering. Which transmission do you have now?
Why do you want to change it as the Mark 8 is a modular motor and any transmission that bolted up to the 4.6 already in the car would bolt up to the Mark8.
But to answer your original question. Either. The only real consideration is to match the number of OSS teeth that the PCM is expecting. In that regard the T45 is more likely to be correct. If it's an early 3650 likely it will be correct as well. Late model 3650 may have a different number of OSS reluctor wheel teeth.
If you do happen to get a late model tr3650 with the different number of OSS teeth it can be corrected with a custom tune just like a rear end change.