03,04,05 4T45E trans ?

[gectek]

ok i have an 02 GT and need to overhaul it, but its my daily driver, so i found a few trans that have very few miles for good $$$ and am lookin at getting the best of the 3, i found an 03, an 04, and an 05, so can anyone tell me if i would have problems with dropping any of those in my 02? i know they used diff solenoids, but they come with the wiring harness so i should have to worry about the diff connections. what probs might i have

[AaronGTR]

Actually the solenoids should be exactly the same between years and you shouldn't have any problems using your stock harness. They don't mention anything about changing them. Most of the changes they made between years where all internal. The upgrades made to the valve body, pressure regulator valve, 2-3 accumulator valve and bore where made on the 2002-2003 year 4T45E so your current tranny probably already has it and any newer one you buy will certainly have it.

In 2003 they added a more accurate line pressure control solenoid, sealed pressure switches, and an improved driven sprocket support thrust washer.

In 2004 the only things they changed that would affect your application (the grand am) is they added higher capacity pump shaft and input sun gear thrust bearings, and a new case air vent and elimination of the TC clutch feed limit valve (both of which are fairly inconsequential and won't affect how it operates).

So I'd say you'd be good with an '03, and an '04 or '05 would also be fine or only slighlty better. In '05 they didn't change anything really other than adding new applications so it doesn't matter which year. All these specs can be found on the gm powertrain website. Other than picking which one you want, it should be a straight swap out and bolt in procedure.