I'm interested in what front and rear ends y'all have been successful at swapping into you 6400 frame. I know the pre-90s ish P30s are a good candidate and I think I have also heard that a Chevy 3500HD is a good donor if it's pre 95 or something. Wondering what else people are using other than these two. In theory most things can be swapped in, but some are going to be easier than others. I would ideally like to only swap in things that are rated for the same GVWR or more.
Is there a good reason not to run what's already there? No sense opening up a can of worms when it would probably be simpler to rehab what you've already got. Jerry
"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt! There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway Love your enemies and drive 'em nuts!
There has been a lot of discussion about rear end swapping and front axle parts replacing drum brakes with discs. At the top of several discussions are notes regarding your exact questions by Grigg and others. Read up on all those to get a start.
I have replaced front axle 2 ton and larger drum brakes with disc brakes from ‘91-‘01 P3500 HD spindles/hubs with 10 on 7.25” volt pattern, tie rod behind the axle trucks, keeping wheel inside the fender, using original axle, on two of my trucks. Delphi(Saginaw) power steering also.
Disc brake rear axle(D-80) on above trucks come in two widths, narrow fit 7’ bed width. Wide fit 8’ bed widths. D-80 and other axles come with modern axle ratios depending on engine choice.
22.5” wheels no longer exist, unless one is lucky, there are options. 19.5” wheels seem to be plentiful, if one can handle smaller OD tires than original.
The same disc brake hubs/spindles come on other trucks than GM factory bodied trucks.
Get out your scale, start looking around and measuring, back alleys, wrecking yards, abandoned yards. Some fabrication skill required.
Pictures show trucks with useful disc brake running gear. I got my spare set from a school bus with GM V-8 and auto trans.
Ed
Last edited by EdPruss; 03/23/20234:31 PM.
'37 GMC T-18 w/ DD 4-53T, RTO-610, 6231 aux., '95 GMC running gear, full disc brakes, power steering, 22.5 wheels and tires. '47 GMC 1 ton w/ 302, NP-540, 4wd, full width Blazer front axle. '54 GMC 630 w/ 503 gasser, 5 speed, ex fire truck, shortened WB 4', install 8' bed. '55 GMC 370 w/270, 420 4 speed, grain, dump bed truck from ND. Works OK.
