Diff Question

[Stu]

I have been a lurker for some time on this site, not having an F truck sort of meant I couldn't add to much. Incredible site by the way and so much information so willingly shared, I love that.

I have bought a 1972 F 250 dually 2wd which I was going to do up, however funds are now limited so I may sell it.

I recently bought a 1976 F250 2wd and I really would like to put the 72 dually diff and springs straight under the 76 model.

I didn't relies at the time that the 72 dually has a 34 inch chassis rail and the 76, 38 inch rails. I tow or will be towing a very heavy boat that weighs around 7700lb mark.

Is there anyway at all I could modify anything that will enable me to roll the dually diff lock stock and barrel under the 76??

They both have the same 8 stud wheel pattern.

Stu

Australia

[sargentrs]

Im not sure about that conversion but I have seen mods where they went the other way of putting a dent side suspension under our trucks just by moving the spring perches. So it sounds possible but you'll have to measure both for clearances.

[Randle]

Stu I would check your frames rails, the 1/2 ton changed to 38" in 73, 3/4 ton didn't change from 34" to 38" till mid year 77, and the 1 ton stayed 34" thru the 79 model year. If yours is a 76 it should interchange.

[Stu]

I measured the 1972 dually frame rail, outside to outside at the wheels which came to 855mm or 34 inches. I then measured the 1976 model at the same spot and it came to 955mm or 38 inches.

I guess the question is, can I move the spring perches out 2 inches either side and still have some clearance between that that and the inside tires?
If not could I potentially use a spacer to push the wheels out a flys dick?
Its a pain not having the 76 F250 here just yet. Im picking it up in around a months time however I did take the measurements before leaving.

I have called a few F250 wreckers in Australia and I get as many different answers, its doing my head in really.
Some state they should all be the same rail width, others so no way, cant be done, other wouldn't have a clue, I fall into that category.

Pleeeeese help.

Stu

[Randle]

I'm not sure what model you have you can check out this link. http://www.fordification.com/tech/chass ... arison.htm I do know my 76 350 is 34". You can measure from the springs to the inside of the tires and see how much clearance you have.

[Stu]

My 72 F250 dually is 34inches, the 77 F250 single rear end is 38 inches wide.

[sargentrs]

Granted, it's strictly by eyeball, but from looking at this drawing http://www.fordification.com/tech/images/bb70/p10.gif there appears to be adequate room to slide the spring perches out 2" on either side and still have the tires clear the springs. You could also get wheels with the appropriate back spacing to move the tires out a little more to compensate if you need more clearance.

[Stu]

Thats schematic is of a 4X4. The diff I wish to use is a 1972 F250 dually which I want to fit into a 1976 F250 NON dually.

[Stu]

Here are some photos, all be it bad ones. This is the back end of my 1972 F250 dually flat bed I think you guys call it.

This is the the rear end I want to roll out and then roll under the newer 1976 F250 2wd.

[Madman]

Stu I would check your frames rails, the 1/2 ton changed to 38" in 73, 3/4 ton didn't change from 34" to 38" till mid year 77, and the 1 ton stayed 34" thru the 79 model year. If yours is a 76 it should interchange.

This would be correct for the 3/4 ton since a 76 Dana 44 is a direct swap into 67-72 F250 4x4's. I know I am a day late and a dollar short, but just in case it helps!

[Stu]

Thats what I have said above. The measured width of the 76 F250 2wd is 38 inches while my older 72 F250 dually is 34. Can I make a modification so I can use the springs,diff and wheels from my 72 f250 dually under the 76 f250?