Casting numbers for a 12 bolt

[Stricken1]

My friend picked up a 12 bolt rear. I need to find out whats the spline and gears. The cast is 3896839 and it says gm84 on the pumkin. The axle number is kBH197W92 It's 58inches end to end on the axles same as my 10 bolt.

[Firebirdjones]

I'd have to check my crash book in the shop for that number.

Is the KBH number what you grabbed off the passenger side axle tube??? Thats the number I would need for gears etc....

Do you know if it's leaf or coil spring??? Passenger car or truck???

I can tell you all original equipment 12 bolts have 30 spline axles both truck and car. Truck 12 bolts have a smaller pinion gear diameter which makes them a tad weaker than the passenger car version. There are some other details but would take a while to explain.

I'll run these numbers tomorrow for you and see what this is exactly. Cheers.

[Firebirdjones]

Well I had to get into the truck book to find those numbers.

Turns out it's a 1979 chevrolet truck, conventional cab, 1/2 ton series 10, either a 4X4 or 2 wheel drive. It should have 11 1/8 inch by 2 3/4 inch rear brakes. It's a 3.73 gear open rearend, (non lockup). Hope that helps.

[Stricken1]

Thank you very much!