Besides the tail shaft being different are there any other differences like gear ratios and stuff like that?

 

Internal gear ratios are the same in every 700R4.

 

Thers a few,Itll work but it might not feel the same.It would help if it was the same year, then the pump might have the same amount of viens,the more viens the better.and the servo might be diffenrt,vett 700r4s have a bigger servo then 3rd gens stock.
the spring that connects to the throttle/kick down cable could be a differnt tolerance making it difficult to adjust,and yes tailshafts,but if you have your old 700 you can swap these things yourself.

 

Make sure its a 700r4 from a V8 and not V6. The bolt patterns are different.

 

also make sure the speedo gear is the same color or your speedometer will be off.swap it with the old one.

 

TC dust cover bolt location changed.

Yeah I know, it's a biggie