axle swap

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Sep 30, 2007 | 05:43 PM

ol74hb

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axle swap

will a 78-79 f250 front axle directly swap into a 73-77 highboy

Sep 30, 2007 | 10:17 PM

masterbeavis

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From: Eldorado Ca. USA

your steering will need to be addressed. Its not a direct bolt in swap, but it will bolt into place.

Oct 1, 2007 | 01:10 PM

benwantland

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From: Iowa

My buddy and I are also looking at this exact same swap for his 75 F250 4x4. The donor axle is from a 79. What is different about the steering? The 79 axle looked like it used the same power-assist (hydraulic ram) system, although the cylinder wasn't on the axle that we were looking at. The other issue is the disc brakes. We figured we'd grab the proportioning valve from the 79 and go to the parts store and get a rebuilt MC & booster for a 79, and probably be good to go. Does that sound right?

Oct 1, 2007 | 03:08 PM

ol74hb

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what about the leaf springs and the shock mounts? the 78-79 use a wider leaf spring

Oct 2, 2007 | 11:00 AM

fordsrgrt

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From: clinton iowa

the leaf springs are the same width in the front.i did the axle swap from a 76 f250 to my 74 f 250.you'll need the ppv valve ,and new mc and power booster, and new rubber lines. and possibly a different drive shaft for the front. as noted above steering issues will arise,what i did was just converted to a manual steering arm and got rid of the power control valve assy and all its hoses

Oct 2, 2007 | 02:23 PM

75F350

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Both axles use a push pull style system, so I do not see where there would be a problem. Both D44's use a similar steering arm, and you can still use the Hydro assist system if you change the tie rod to accomodate it. Since you already have an axle under the truck, you have everything you already need. This is a 100% bolt in modification.
The conbination valve is simple enough, and can be bought at your local parts house. Do be prepared for a little confusion when selecting your master cylinder, as there were many configurations. Also be prepared for sheelling out a bit of cash for the 350 booster and master, these puppies were not exactly being given away.
A little suggestion with your lines, would be to install stainless steel braded ines instead of factory rubber ones, they will be much better, and last longer. While the factory rubber ones have lasted over 30 years, the upgrade lines wil be a nice upgrade.

I Forgot! Since you are going to be using the high pinion front axle, your driveshaft may be a little long.
If your truck is lifted you may not have a problem, and hey, if it is lifted yo may consider scrapping the push pull steering anyway.

Last edited by 75F350; Oct 2, 2007 at 02:26 PM.

Oct 3, 2007 | 01:39 PM

benwantland

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From: Iowa

Quote:

Originally Posted by fordsrgrt

the leaf springs are the same width in the front.i did the axle swap from a 76 f250 to my 74 f 250.

Well the 73-77.5 F250 4x4's were essentially the same, but there were some major changes in mid 77, I just can't remember what they all were or how they affect the swap we're looking at.