Full-Time axle into truck with NP205 transfer case?

[Rodent]

I saved a '77 K20 from the crusher awhile back intending to use it as a winter beater. Truck currently has a SM465 with a NP205 part time case I believe. The front axle is pretty messed up, its been ran for a long time with busted axle joints, the ears are ground off the knuckles from the shafts just slapping and flopping around in there and everything is rusted to hell and back anyway.

I have another K20 chassis in the backyard from another project with a full-time 10-bolt with new calipers and such, and was wondering if its possible just to swap this entire axle into my part-time equipped truck.

This is a winter beater, I do municipal plowing, and I only have like a 3 mile round trip to work. Gas mileage is no concern. My Bronco II crapped out on me at the end of last winter in 16" of snow. Figured I'd just go bigger and simpler.

[kwmech]

You can swap the entire assy, just make sure the ratios match.

[Rodent]

Oh yeah. I think they're both 3.73s. If not, I'll just swap the rear axle too. The old chassis has a posi rear.

[1976gmc20]

The only difference was that the "full time" front axles came without [un]locking hubs - just a solid flange that permanently connected the axle spline to the hub.

So you could rob the lockout hubs from the old axle if they are any good or just run it without lockout hubs. I'm not sure that it really makes that much difference as all the newer stuff just turns all the time anyway. I hardly ever unlock the hubs anymore on our Suburban, and my K1500 has the central disconnect permanently engaged.

[Rodent]

Yeah I've heard some conflicting stories on what you can swap out and this and that. I personally don't care if I can unlock the hubs or not for what I'm doing with this truck. Simpler the better.



The day I brought it home. Put a battery in it and drove it. Burned and leaked almost a quart of oil in 45 minutes though! Currently in the process of swapping engines.

[1976gmc20]

Well, at least you won't be afraid of scratching it

Main reason I bought my C-20 back 20 years ago, is that all the K-20s looked about like that and cost twice as much as a 2wd in nice shape

[Rodent]

And I won't feel guilty about driving it in the salt either, I really hate rust.

[andrewmp6]

If you don't like locking hubs you can get a drive flange kit which locks it forever.

[1976gmc20]

Originally Posted by andrewmp6

If you don't like locking hubs you can get a drive flange kit which locks it forever.

That's what the axle from the full time (NP203) pickup should already have

I worked for a Chevy dealer about the time those first came out. I joked to people that I had converted my K20 pickup (early 1973) to "full time four wheel drive": I locked in the hubs

All I had to do then was put it in "4-loc" (4-hi) when I needed real 4wd.