2002 Gmc Sierra 2500hd 4x4 Automatic Transmission

[jacksonjw81]

All I am looking for is what transmission I have so I know how much fluid and type I need to buy for it and the differentials.

[yukon25008.1]

if its an 8.1 truck it has an allison

if its a 6.0 its a 4l80e

the front and rear diff,s get 75/90

[kifels]

there are several free VIN Decoder that you can run you VIN through and it will provided you with pretty much all the info you could need. for EX:http://www.compnine.com/vid.php this site breaks alomost everything down, was dead accurate with my truck.