Transmission Swap
Transmission Swap Information
FOX and SN95 Guide
So you are thinking about swapping a different tranny into your mustang, but are not sure what exactly you need, and what you might have to do to get it working correctly with your setup. Hopefully this guide will be all that you need. I have done many of these swaps, and have gathered info on what I don't have experience with so you don't have to. On to the goods!
T-5 to C4-C5
This is a real common swap for people looking for a relatively cheap and very strong automatic. The c5 is a later version of the c4 found in early 80's model Mustangs that features some better case mods than the earlier c4's, but they are basically the same thing. The c4 can easily be modified to c5 specifications. One confusing factor about this swap is the difference between the big and small bellhousings that are available forthese transmissions. If you find an early model transmission (pre ~75), it will have the small bellhousing that is required with the 157 tooth flexplate. These 157 tooth flexplates are all a 28oz imbalance, so if you want to use it on a late model 50oz imbalance motor you will need an aftermarket 157 tooth flexplate that has been balanced to 50oz. The later c4 models have the big bellhousing from the factory, and they use the 164 tooth flexplate as found on AOD Mustangs.
T-5 to AOD/AODE Conversion
So your thinking about putting an AOD in to replace that T5 for everyday driver duty, or because you want the consistency and easier starting line hit of an automatic, but still want to have overdrive. If you are planning on the aode, you will need an aode computer and transmission wiring harness. A very good choice to program the shift points of your AODE is to go with the Baumanator TCS.
AOD to T-5/Tremec 3550
This is a very common swap for people who want a stick in their automatic equiped cars. This swap is straight forward, but requires quite a bit of time and effort, mostly coming from the pedal swap.