Does my GM 12 Bolt have a factory locker?

[mac52]

Hey Guys,
I am new to the whole Forum thing. But I have a 75 chevy K10 with a NP203 transfer case (full time 4wd). How can I tell if my 12 bolt has a factory locker or is an open diff? I checked for the g80 code on the glove box but didn't see it. Not sure how to tell. Any clues would be nice. Thanks!!!

 

[jmbcary44]

not sure, but I don't really recall reading about a g80 in the 12 bolts from them but I could be dead wrong also...could always open it up, new fluid is always good too

 

[mac52]

Thanks, that is where I was headed next, but wasn't sure if there was a way to test it without busting it open first?

 

[Pender1]

Thanks, that is where I was headed next, but wasn't sure if there was a way to test it without busting it open first?

Check your axle code

http://www.gmsquarebody.com/forum/showthread.php?t=4185

 

[mac52]

That last link totally answered my question I was able to find the code on the diff. It is open thanks for that.

 

[87scotty]

Couldn't you jack up the rear end put truck in neutral and spin tire see if they both spin forward or not?

 

[Pender1]

That last link totally answered my question I was able to find the code on the diff. It is open thanks for that.

Glad I could help.

Couldn't you jack up the rear end put truck in neutral and spin tire see if they both spin forward or not?

Yes, that is the definite way to check. Sadly not everyone has easy access to floor jacks and such.

 

[Don5]

Take it out on a gravel road, stop, and you know the rest.....

 

[87scotty]

My ole warn out 350 won't spin the fronts :-(