K10 Rear axle ID

Disclaimer: Links on this page pointing to Amazon, eBay and other sites may include affiliate code. If you click them and make a purchase, we may earn a small commission.

T-roy K10

Member
Joined
May 9, 2023
Posts
48
Reaction score
76
Location
mississippi
First Name
Troy
Truck Year
1985
Truck Model
K10
Engine Size
350
I know it’s a 12 bolt, even though everything I read says a 1985 k10 never came with a 12. Lady at DMV said it was either military or some government agency. It has the loud clunk in reverse and seems to have too much okay when turning yoke by hand (nothing up and down). Limited slip is also worn out and axles/wheels wobble slightly so they are bent.
the question.. I need to pull the axles to Id the splines and length or does anyone know those specs?

You must be registered for see images attach
You must be registered for see images attach
 

legopnuematic

Licensed Junk Dealer
Supporting Member
Joined
Oct 27, 2016
Posts
2,181
Reaction score
5,152
Location
MO
First Name
Spencer
Truck Year
1971, 1̶9̶7̶4, 1976, 1979,1̶9̶8̶5, 2002
Truck Model
Dart Swinger, Sierra 10, C10 Cheyenne, C10 Big Ten, Silverado 10, Ram 2500
Engine Size
225/6, 350 c.i., 350 c.i., 5.9l Cummins
From the factory it would have been a 10 bolt, someone along the way swapped one in. They are basically a direct swap. My friend put his 87 10 bolt front and rear under his 75 K5, with the dana 44 and 12 bolt from the 75 under the 87 to make it still roll.

Why would someone swap a 10 for a 12? Who knows at this point.

AFAIK, all 12 bolt truck axles are 30 spline, 1970-1981 12 bolts should all use the same axle lengths. 5 or 6 lug depending on 2wd or 4wd.

With that said, safest bet is to pull them to inspect and verify to be certain.
 

Forum statistics

Threads
43,422
Posts
935,288
Members
35,273
Latest member
zcostilla
Top