Does anyone know if there is a difference in the thickness of the metal used to make the frames on 73-79 trucks? Would a 1-ton frame be thicker than a 1/2 ton frame? Is there any advantage in building up a 1/2 ton with a 1 ton frame??

Thanks
Howard

 

I know that the '76 3/4 ton frames are a gauge or two thicker then the 1/2 ton of the same year. My '76 Explorer is 3/4 ton but I have changed the running gear to 1/2T and kept the 3" rear springs, 1/2t has 2 1/2". Tires and front end parts are easily and cheaper to get plus I could change rear gear sets to fit my driving. I have a 3.25 positive traction in now. This set up has worked for me for 20 years. I am sure that's more info then you were looking for.

 

Frame thickness is the same, 1/8". Although, 1 ton frames are stouter than 1/2 ton frames. Not sure about 3/4 ton frames. Newer frames are thicker and taller.

 

Yes, the metal may be the same thickness but the frames are different in strength. for example in 1973
F100 2wd 117"wb=3.09 section modulus
F100 4wd 117"wb=3.92 section modulus
F250 2wd 133"wb=4.14 section modulus
F250 4wd 133"wb=5.58 section modulus
F350 2wd 137"wb=5.58 section modulus
F350 2wd 161"wb=7.84 section modulus
as the GVW increases so does the frames strength.
Source: 1973 Ford truck Data Book
Hope this helps with your decision...............Bart

 

What is an F100 2wd 133" wheelbase?

Josh

 

My '76 F-350 Super Camper Special Has a 8" Deep Frame.(Proof is in the link below) (Description Below Picture)
http://i684.photobucket.com/albums/v.../090205210.jpg


(The two above pictures are of my '76-SCS.)

('73 F-100 2WD)

('74 F-100 4x4)

('75 F-350 Dually 2WD)

('76 F-250 4x4)

('76 F-100 2WD)

('77 F-150 4x4)

('78 F-250 2WD)

('79 F-350 4x4-First year for F-350 4x4)

Hope I helped.

 

my 76' highboy's frame is 3/16". So aparently they do vary in thickness as well as depth of channel. Post #4 probably reflects this.

 

78-f150 is 3/16 as well. height of channel varies dependent on where it's measured. Mine goes from seven in spots to as little as five.

 

79 f150 is 3/16 as well. Well at least what is left to the frame

 

my 75 highboy is 1/4 inch in the front.

 

F100 2wd 133"wb=3.26 section modulus

 

The reason I asked is that im working on at '74 F100 and have a 77 F350 im parting, thought if the 1ton frame was better, that i'd swap them. Possibly make for a better ride?

Thanks
Howard

 

I would guess IF the 1 ton frame is indeed thicker and more rigid, the resulting ride would be worse/stiffer.

my 78 used to be 2 wheel drive f-150. I wanted 4wd so i swapped a frame from a 78 f150 4wd. The ride quality of the 2wd was light years better than the current 4wd. I guess whether that has anything to do with frame rigidity/ thickness I can't say. Maybe it's just due to the 4wd susp. setup.

 

I would guess IF the 1 ton frame is indeed thicker and more rigid, the resulting ride would be worse/stiffer.

my 78 used to be 2 wheel drive f-150. I wanted 4wd so i swapped a frame from a 78 f150 4wd. The ride quality of the 2wd was light years better than the current 4wd. I guess whether that has anything to do with frame rigidity/ thickness I can't say. Maybe it's just due to the 4wd susp. setup.

 

well we all have to remember that after 30-40 years, these frames do lose thickness over time due to rust, also i don't think the frame gauge changes, now the C frame dimensions could change, but i don't think the overall gauge changes, also the main factor i see between a F-100 to a F-150 to a F-250 to a F-350, is the suspension changes, from what i see the suspension and the axles are the major changes, thus if you go from F-100/F-150 to a F-250 and up you lose the nice ride, due to the fact of front leaf spring suspension and stiffer springs, anyone will tell you the F-100-F-150 front coils give a better ride, and if you want the best riding truck of them all, and the closest thing to a car like ride then the rwd F-100 was your choice, its car like suspension gave it a smooth ride (plus weaker, more grocery getter suspension, mind you after '75) vs. tougher stiffer springs found in the F-150 and up, but i see you have a 74 F-100 so it is more closer to '75 F-150 since the F-150 was to split the difference between the F-100 and F-250 for coming emission reasons, but overall you would actually reduce ride comfort with a F-350 frame, it will be more rigid then a F-100 frame and suspension, personally if i was only looking for comfort, i would stick with the F-100 frame, but if you plan on more, then the F-350 frame seems like a good choice, just take note you will lose ride comfort, now i know many hard core F-250+ owners might disagree, but the fact is the front leaf springs give a poor ride compared to coil springs, either way you got a great frame, and its all about what you want to do with the truck, also does the F-350 frame come with the upgraded axles? that will also effect the limitations of the truck, if it has the F-350 axles you can do just about anything with them, it will also limit your wheel choices, generally the F-100/F-150 5 lug pattern is easier to find rims for, just another heads up, also i don't know everything about the F-250+ trucks, but i think there axles also have drum brakes in the front? i am not sure what year F-250+ got disc up front? this is also another heads up, plus the heavy duty axles will add to the trucks overall weight, thus MPG will be reduced, just another heads up, all these things are alright don't get me wrong, but if you don't need the super strength of the F-250+ then the costs out way the benefits, personally the F-150 suites my needs, but others may need a tougher truck (F-250,F-350) or a better ride, so they would get a F-100,

so good luck and keep us updated, also i would also factor in condition of each frame, if rust is a problem in the F-100 frame, then i would swap in a heart beat if the F-350 frame is better,

hope this all helps out, also i could be wrong on the frame gauge, but as far as i have seen they all use the same gauge?


-Brent