Does the number on the transmission supposed to match VIN number? (2001 Xtreme) trying to figure out if the trans is original. Took my car to a shop and he said the transmisson needed to be rebuilt. Long story, but I basically got robbed. I'm wondering if he actually rebuilt my trans or if he went to a junk yard and put a different one back in. The number on trans doesn't match the vin at all. Any help is appreciated

 

I don't think there is a number to which you can tell this. Most salvage yards mark the used transmission in some way. You either trust your mechanic or you don't. If you don't trust the shop you should make a permanent mark on the part to be repaired and take pictures. Specify on the work order you want your original equipment rebuilt. What is the warranty you got?