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obs frame interchangeability

some zilch

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I have a '97 F-super duty obs (2wd, reg cab, straight front axle w/leaf springs, 10 lug rims)

I want to put the F-SD suspension and axles under a crew cab f350 of similar year. Does anyone know if most of the holes will be in the f350 frame?
 
2wd or 4wd F350? The F-Superduty uses the 4wd frame for the leaf spring hangars. It should be a direct swap into a 4wd truck. If the F350 is 2wd however, youll have to cut the front shackle mount out of the F-Superduty frame (or any other leaf sprung 92-97 frame) to put into your truck's frame. The rear spring hangar will bolt up but i dont think the holes are in the right place, as the radius arm bracket would be there.
 
What are you trying to do?



Don't overlook a cab swap, or a cab clip, ie, cutting the a pillars and across the floor, making it a crew cab, not messing with the firewall and such, been done in many driveways

I have a 95 fsuper duty 7.3 5 speed truck here, if I ever decide to make it a crew, that's how I'm doing it
 
Aren't F-Super Duty a 34" wide frame?

Is the F350 a cab and chassis truck? Seems like the regular F350 had a wider frame, but I might be misremembering.
 
AKnate said:
Aren't F-Super Duty a 34" wide frame?

Is the F350 a cab and chassis truck? Seems like the regular F350 had a wider frame, but I might be misremembering.
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In the back yes, frame "dovetails" behind the cab on a C&C truck.

Putting a crew cab on a regular cab C&C frame, the front mounts will line up, rear would have to be fabricated. Might need slight body lift for the floor pan to clear the frame, if it bumps up behind the cab.

An F Super Duty frame is a lot beefier than a F350 frame, which is the benefit to it. The F Super Duty 2wd monobeam drop axle is nothing special. The rear end spring perch width on F Super Duty would be less than a pickup bed "styleside" F350 is set up for. You'd have to look and see if you can move the perches outboard some. I know on the F350 cab and chassis trucks, there's no room to move the perches, I don't have a F Super Duty axle to look at.

If you dont yet have a crew cab, find a 4wd cab and chassis one (rare?), and swap the F Super Duty shit under it. Front will bolt right in, using the F Super Duty springs. Unsure on F Super Duty rear spring length, should be the same.
 
posford said:
If you dont yet have a crew cab, find a 4wd cab and chassis one (rare?),
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Why would it matter what he sources the cab from? Worst case he has to add/modify a cross-member to support the back of the cab.
 
arse_sidewards said:
Why would it matter what he sources the cab from? Worst case he has to add/modify a cross-member to support the back of the cab.
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Read. Left to right, top to bottom. Just because you said cab swap doesn't mean my answer is only im reference to a cab swap
 
posford said:
Read. Left to right, top to bottom. Just because you said cab swap doesn't mean my answer is only im reference to a cab swap
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I get the other differences.

I'm saying that if the dude is trying to build a 10-lug crew cab on SD axles then slapping a crew cab cab sourced from whatever donor he can get his hands on onto a an F-superduty rolling chassis seems like the easiest option, no?
 
I dunno if you'll find a F-Superduty crew cab? I don't think I've ever seen one. So if you wanted to use that frame with a 4-door cab you're stretching the frame. And then like posford said the back half is a 34" wide straight rail frame so you can't put a stock box on it easily. At that point I actually think it would be easier to swap the 10 lug axles into the crewcab frame.
 
Does anyone know if the cab and chassis f350 frame is the same as the f-superduty?

It seems both the 2wd and 4x4 c&c versions have the frame re-enforcement in the middle.
 
Levigarrett76 said:
Does anyone know if the cab and chassis f350 frame is the same as the f-superduty?

It seems both the 2wd and 4x4 c&c versions have the frame re-enforcement in the middle.
Click to expand...
The F Superduty is a thicker frame for sure. Not sure about the profile, if it matches the standard C&C frame. I have one but its buried last I checked.

arse_sidewards said:
I get the other differences.

I'm saying that if the dude is trying to build a 10-lug crew cab on SD axles then slapping a crew cab cab sourced from whatever donor he can get his hands on onto a an F-superduty rolling chassis seems like the easiest option, no?
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I guess it depends on what bed he wants. If he wants a crew cab style side truck, the F-Superduty chassis would suck, because length won't be right without modification, and may require a slight body lift to clear the curve of the frame. You're getting into the booty fab side of shit quickly.

Buy whatever configuration of truck he wants, but 4wd, and the parts should about roll under. Pull transfer case and install F Superduty trans mounted ebrake. Simple as fuck
 
Levigarrett76 said:
Does anyone know if the cab and chassis f350 frame is the same as the f-superduty?

It seems both the 2wd and 4x4 c&c versions have the frame re-enforcement in the middle.
Click to expand...
Google search "ford body builder manual pdf" and fine one from the 80s/90s. It will have illustrations. IIRC they are really close but not exactly the same.
 
posford said:
The F Superduty is a thicker frame for sure. Not sure about the profile, if it matches the standard C&C frame. I have one but its buried last I checked.
Click to expand...

Is it thicker front to back or just from the back of the cab to the rear of the frame?
 
Pics from my 97 F-350 C&C frame mid section

9841651.jpeg
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6514651651.jpeg
 
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Seems like the frame was taller on the F-Super Duty.

I had a 97, and still have a 97 F350 C&C. Both 4wd. The SD was a Quigley conversion.
 
I saw this driving around this morning. Couldn’t get a good look, but pretty sure it’s a crew cab and a bed bolted onto an F-Superduty frame. Tires were narrower than the fenders, body was lifted, front axle was an I beam. Bed looked shortened
BF72FCDA-0176-4D28-A6AB-23D1D5FD41A7.jpeg
3F7C165C-043F-4025-BD84-B56B73A8E554.jpeg
CA1A0FDE-8386-433F-8390-6496DB4EE43B.jpeg
 
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