I was looking at 'what if' I swapped F450 axles under a 2017 350 vs a 450 pickup regular cab. I looked around quite a bit before finding the info. Posting in case someone else is curious.

Interesting the F450 PU CC aligns to the C&C data, but the PU regular cab has a higher radius for the given wheelbase. Its like they increased the radius on the F450 pickup with the regular cab. Not sure why the F450 RC has the same turning circle as the F350

Turning Circle as function of wheelbase below for F450.

 

Thats some fancy algebraic siferin youve accomplished there.
I dont know about radius claims by Ford for a given cab configuration. But...
Nothing compares between the 350 and the 450.
The frames are different, the 450 axles are significantly wider, allowing sharper wheel cut.
I have a 2017 450, Reg cab, in a mason dump configuration.
And a 2019 CC F250 short bed pickup.
Not sure how the wheelbases compare. Probably the pickup is longer.
But the 450 turns in noticeably tighter than the 250.
And its not just about wheelbase. Its the tighter turn in. The 450 almost seems like you could turn the wheel so tight the wheels wont rotate but slide sideways.
I never thought about frame width but the 450 frame is a completely different design. Ill have to climb around under there again but I dont think its boxed. Its a much heavier duty truck.
Enough so I think a front axle swap would be more involved than just the axle. And plastic flares from the 450 cab.
Interesting thought though.
The 450 front end has a full compliment of grease fittings where the 250 is greaseless but for the U joints at the spindles. I havnt really heard the 450 guys commenting about death wobble either. I dont know if theres notable difference in geometries either.
For the sake of discussion....

 

Google Sheets does the siferin...

From what I read the turn in on the 450 axle is 45 instead of 35* on the 350. The wider axle and knuckle geometry allows for the wheels to turn further. I had read the F450 frame on the pickup and C&C was boxed till the end of the cab, but the C&C is channel cab to tail for easier upfitting (also more flex). I think the track widths are the same between C&C and PU models... so thinking the frame construction isnt a factor in radius.

I had a 2017 SC F450 C&C but a long wheelbase. It turned quite good even with the 12' flatbed. It was just too much bed. At the time I needed a diesel tank and a flatbed and it was turnkey and priced right. I had the C&C for ~2 years and sold that truck last month for quite a bit more than I paid for it.

Ultimately I want a truck they don't make, a SC, a short wheelbase, the 45* turn in, and I prefer the options in a PU model. Swapping the front would come down to differences in the 350 and 450 frames ... you say these are different up front?

I would prefer to get a later model, but might have to go back and look at pre 17 trucks with a 6.7. I read some folks have swapped alxes on those.

 

Much of the 450 and up front track width (appears to) comes from the hub adapters. Not saying the front axle would be a direct swap, but maybe it's not too far off where it matters.

 

Pretty sure my 2020 F350 SC C&C turns at 40 degrees not 35 as stated above. You gain 5 degrees with F450.

 

I started sifting through part diagrams and the housings, arms, and whatnot are common. Spindles, hub, adapters, brakes differ but thats all on axle. Master cylinder, steering box is a different dash number and that seems what needs to be sorted out.

I read somewhere on this forum? it was 35* turn in on the 250/350. I have no idea the actual. The data says its ~13% difference and nearly 6' for the wheelbase I'm looking at.