How do I know which transmission I need?

[TBoomer]

I am shopping for a used transmission for my 01 LS. It's a V8 with sequential shifting. Two choices keep coming up.
Model # 5R55N ID 1W4P-AA
Model # 5R55N ID YW4P-AA

Which one? Or how do I find out?

 

[FASTLLS]

You could ask Maxx ------------->

He could run your VIN and tell you.. I also think there is tags or it is stamped on the trans..

 

[TBoomer]

Got it. Thanks!

 

[FASTLLS]

no problem..