I want to know how I could tell the difference between a J Spec D15 tranny and a USDM D15 tranny.

Thank you.

 

USDM trannys have USDM VIN numbers on them. JDM trannys have a unique identification number on them aswell, however they are not as long. The tranny's also have a model number as well, which can identify them too (S80, S1, Y1, etc.) JDM D15bs were the only ones with LSDs.

 

they have many versions of the d15 motors in japan and usa.. but trasmission all have the same or similar gearing.. only thing you have to watch is the splines on the shaft..