Resurrecting the thread here; The Mach 1 in 03 had the 4R70W, in 04 they upgraded to the 4R75W just like the Marauder. These vehicles had the exact same drive train when it came to automatic transmissions. The Marauder had a different upper intake is all that was different. As for the difference between the 70 and 75; reverse sun shell is stainless steel design and gear set is hardened with bearing improvements, the pump was improved, new intermediate piston assembly and solid sealing rings, there's a different ring gear for the speed sensor.
All Gen 2 Lightning came with a 4R100, they never came with a 4R70w or 4R75W. Gen 1 Lightning E4OD only. The 4R75W first came out in 04.
In order to install a 4R75W in your 96 GT you will need to change the pin out of your main transmission connector on the pass. side of the Trans. Then you will need a different speed sensor and last you will need a custom built program to run it properly or it will shift through the gears early.
The 96 4R70W was the first improvement from the AODE/4R70Ws from 92 - 95. The case was improved for better oiling and strength. They are still not considered good enough for real high hp. In 98 the Trans was improved again. The valve body in 99 was then the next big improvement. In 01 the transmission was again improved slightly and better valve body. 03 and 04 were the last improvements and where you get the 4R70E in 03 and 4R75W in 04. If you want a good transmission to start out with for any type of performance then I would start a 99 or newer. For any real serious power I would start with a 4R75W. I've got a couple of them running in the 9s right now.
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