k-10 axle questions

[jrlucky]

I'm getting a half ton four wheel drive running gear on a trade this week (70-72). The bad part is that it doesn't have a rear axle. Were the 73 & up rear axles the same width? Just wondering since the front axles (72 and earlier) were different and the later ones are a lot easier to find. I know I will have to double check the gears. Any help would be grateful so I can start my body swap. thanks

[andrewmp6]

The 4x4 part of this forum will know better then anyone.

[Mike C]

They are close enough to work. Both mine and my kid’s project have 8 lug semi-float axles swapped in from mid-80’s K20 Suburbans.

You can also run a 67-70 6 lug drum axle if you are relocating shocks and spring mounts. Even a coil spring setup. Just know that the earlier 67-69 housings and maybe some early 70’s are 1.5” narrower.

But the tape measure is your friend. And it may be cheaper to buy a matched set of axles from a 73-91 square body than to re-gear your newly acquired rear whichever way you decide to go.

Good opportunity to go to 8 lug axles for strength as even the semi-float 14 bolt is WAY stronger than the 12 bolt. Once again depending on what you plan on doing with the truck. Big tires, manual transmissions, powerful engines all eat the 12 bolt IME.