We have an '85 F250 4WD Diesel. The body and
cab are pretty much shot (rust). We would like
to transplant the drivetrain into a donor vehicle.
What year trucks should I look for? My thought
is that we would bolt the existing drivetrain + suspension
to the new vehicle and leave our old frame and
body behind. Will a F150 frame work or does
it have to be an F250 frame?

 

The F-250 should have front leaf springs, so you need a 250 or 350 frame of the same configuration (cab & bed lengths). Or you can change it if you get the driveshafts with the new frame. You may still have to have them cut to match the length of your transmission, though.

If your frame is OK, it would be MUCH easier just to swap the body.

 

Thanks Steve. I am surprised that it is much easier
to swap the body. How about all the junk on the
firewall. Doesn't this have to be relocated? Wiring
harness ....

I see that we need the F250 or F350 frame. I
suppose if we were just doing the body, we could
use the F150 body. Do you know what year models
are compatible?

 

'80-86 F-150 to F-350 cabs have all the right holes for your current interior parts and would be direct swaps, but '87-91 is close enough if you don't mind a little fabrication &/or upgrading. If you're comfortable with heavy wiring harness mods, you can make the '87-91 harness run your engine, but I mean HEAVY. That would make using the '87-91 interior easier, but it's not really worth all the hassle.

Same year & model range for the direct-replacement front clip (fenders etc.), but including Broncos. You can go as far up as '96 with remarkably few problems, and that's a popular swap. Just be sure to get EVERY piece of painted sheet metal forward of the firewall from the same body style to make it work.

For a complete bed, '80-96, but there's some way to mix the tailgates. I'm not into pickup bodies, so I don't know the specifics on that swap.

 

I am looking for just the opposite of you. I need a rusted out body and no drivetrain. If you end up needing to get rid of your frame and rusy parts, let me know.

 

If your donor cab comes off a non diesel, be prepared to swap some of the wiring, mostly the extra warning lights, and, the glow plug circut. This may or may not be plug and play, I have an 85 that we pulled a diesel out of, but, it's wiring harness has more than a few modifications.
Evan

 

If you have a manual transmission, there's one more consideration for the '80-up bodies.

'80-'82 trucks (and Broncos) use a mechanical clutch linkage, '83-up use hydraulic clutches. The firewalls are different where the pedal hanger mounts, and the lower firewall/upper floor is different (where the mechanical linkage rod passes through).

Bodyside molding lines and creases were the same from '80-'97, so front clips, doors, cabs, and beds from all those years will line up nicely. However, the shape of the fender wells changed in '87.

The '86-earlier fender wells are flat across the top and angled open more toward the rear (a Ford truck styling cue that goes back to the late '50s). The '87-up fender wells are more rounded and symmetrical around the tire. If you change the '80-'86 front clip without changing the rear (e.g., bed), the fender wells won't match.

If you change the front clip style, make sure you get the radiator support bulkhead (some call it a header panel) for the new front clip. Those are not interchangeable with the different sheet metal styles. And don't forget the cowl panel (between the windshield and hood) to go with the new front clip. The cowl panels are interchangeable between all years, but the look is more complete if the cowl style matches the front clip. The later cowls with small round holes are also better at keeping tree leaves and other debris out of the HVAC ducts.

 

Actually, all 82 and later cabs are set up for the hydraulic clutch, you just have to drill the firewall, and swap the pedal and the rod it is bolted to over, and, the only difference in the lower part of the floor is that manual linkage trucks have a hole, while juce clutch trucks don't, the stamping itself is the same.
Evan

 

We have an automatic with the diesel so the clutch
problem is not an issue. I need to assess how much
rust we have on the frame before I decide to move
the drivetrain into a new truck or put a new body
on the existing frame. Are the 2wd and 4wd frames
the same?

 

2wd & 4wd frames for F-150s are the same, except for the rear spring hangers. 2wd has 2.5" 4wd is 3"

2wd in anything else is just like the F-150 (twin i-beam&radius arms), 4wd in F-250/350 is leaf spring, and AFAIK, interchangeable

 

The front end of the frame rails is different on F250/350 frames.

The 4x4 frames have a big dimple pressed into the side of the frame rail to hold the inside of the front leaf spring shackle, and the bottom flanges are cut back for several inches to clear the front shackles. Neither of these features is present on the 4x2 frame rails.

 

I posted on this topic about a Centurion F-350/Bronco conversion doing a diesel conversion at: http://www.fordtrucks.com/forums/sho...613#post935613

Ford Truck Enthusiasts Forums > Older, Classic and Antique Trucks and Vans > 1980 - 1986 F-Series Trucks / E-Series Vans > Egine swap 460 to a diesel...Can I??