We have a 1990 F-350 the back cross member is toasty and the back of the Frame needs help, question is the frames on the F-250 and F-350 are the same wanted to know if the back 2' feet of the frame would be the same as a F-150 and if the are not please explain to us the difference, thought they may be a lighter steel thickness? Also are the cross member the same? We are getting calls on this a lot to fix up these trucks. Looking for some good feedback.
Ty.

 

250HD and 350 are the same except for front suspension (TTB vs D60). The frames are the same. 250LD and 150's had a very different, lighter frame, again I believe they are the same as each other as well, but I can't say that with complete certainty.
-Mike

 

the F-250 diesel used the F350 frame in a pickup. if your F-350 is a cab chassis truck, it has a different frame than the pickup has.

 

I agree with everything stated above.

You can mix and match crossmembers between pickups(f150-f350)

But cab-n-chassis trucks are all on their own

 

Thank you for the feed back have more information confirmed,
will see when we take some more trucks apart and see side by side the difference in any frame thickness on the back 2' of these frames.
Ford Depot.