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'79 Ford D44 width question(s)

themangeraaad

NAXJA Forum User
Location
Halifax, MA
So I have been searching around and doing a bit of research on a D44/9" swap from a late 70's bronco or F150. I plan on running 36" tires by the time all is said and done, so I need something a bit stronger that the stock stuff.

So I have found that the stock axles are approx 60.5" WMS to WMS (I have also heard 58", but I don't know if that was the WMS width). I have found that the '78/'79 F150/Bronco had the HP D44 front and 9" rear that were approx 66" WMS to WMS. Can anyone confirm these numbers?

Also, I have read that a same year F250 has the HP D44 front (heavy duty in some?) and D60 rear, but they are "a bit wider" than the F150 axles. So I know they are a bit wider.. but I couldn't find any actual numbers, particularly WMS-WMS numbers. Anyone know this info? If "a bit wider" means approx 1" wms-wms wider, I may be able to live with that. If it means 2" + wider I may run into issues. Erm.. well I will probably be running into issues either way, but I will cross that bridge when I get there :roflmao:

Long story short I was going to pick up a D44/9" out of a F150, but I just came across a D44/D60 out of a F250 for sale locally. Granted I know there are different things to take into consideration (lug pattern, overall size, strength, etc) but I am ignoring those for the time being and for now just want to compare axle width. I will get to the other aspects of the axles once I know what I am working with.

This is mainly because I currently have stock axles and 33x12.50s that are backspaced so they stick out approx 5" on either side of the rig. I have seen a build where someone threw full width axles (I want to say it was an F150 D44) under their XJ. With "normal" backspacing the tires only seemed to stick out a bit more than mine do now.. I am beginning to think with the correct planning/wheels, I may be able to avoid shortening the full widths and stay relatively close to my current width (a good thing :thumbup:). For 36" tires & selectable lockers, either axle setup should be strong enough... so it is starting to come down to width and availability. Either way I will need new wheels, new driveshafts (or adapters), and other such parts. So those costs balance out.

That and having the HD D44/D60 combo would be badass, even if it's just for the bragging rights:D Thanks for any help!
 
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In stock form, the D44 has the same axle joints as your D30, not much gain as the axle joints are what usually breaks. I'd put alloy shafts on the D30 before I'd spend the effort to do the D44. For it to be stronger, you have to factor in alloy shafts for the D44. BTW, XJ stock width is 60.5".

The stock D60 has 30 spline shafts, smaller than the 31 spline shafts in the 9", and a lot heavier with less ground clearance. No one will think it's cool to run the stock D60.

Not saying don't do the upgrade, just know what you're actually looking at. The good stuff takes a little more work and money.
 
In stock form, the D44 has the same axle joints as your D30, not much gain as the axle joints are what usually breaks. I'd put alloy shafts on the D30 before I'd spend the effort to do the D44. For it to be stronger, you have to factor in alloy shafts for the D44. BTW, XJ stock width is 60.5".

The stock D60 has 30 spline shafts, smaller than the 31 spline shafts in the 9", and a lot heavier with less ground clearance. No one will think it's cool to run the stock D60.

Not saying don't do the upgrade, just know what you're actually looking at. The good stuff takes a little more work and money.

Thanks. I had heard/read about the D60's size (which is why I mentioned overall size as a criteria that I would look into down the line after getting widths straightened out). Would probably end up doing some work to it before it got installed, so I would be doing my best to take care of the ground clearance issues.

Regarding the D44 axle joints, I know the older model D44 had smaller axle joints, but thought that after the mid 70's they had larger axle joints... I am probably wrong, it seems to happen alot :laugh: The issue with that is if I go full width in the rear (9") I would want to have matching width up front... so the D30 would have to go anyway.

I have considered a Ford 8.8 swap for the rear and building the front... but at the same time I would prefer the extra strength of the 9" if it will fit my Jeep as I hope it will.
 
The 8.8 and the 9" both have 31 spline axles, so they're the same strength. Unfortunately, when you first get started and hear things about axle strength, most of what you hear is based on custom axles, not stock axles. All custom D60's have 35 spline axles (unless they are built with 40 splines), and many custom 9" are built with 35 spline axles in 4x4's.

All D44's have the 297x/760x axle joint, except the early closed knuckle 44's....and maybe the very early small Bronco D44.
 
Alright, thanks.

Now that leads to other questions. Basically if I should settle for an 8.8 and build that if needed or if I should go to a 9" and build that if needed. Clearly I need to do a bit more research on my end for stock axle strengths. I started off looking for an 8.8 but then moved my way up to the 9". The 8.8 may hold up to 36's, but I don't know if I will end up staying at 36" once I get there or if I will feel the need to go bigger eventually and build a dedicated trail rig. If the 8.8 & 9 are comparable in strength in stock form, I may still go with the 9" for the added potential.

Another [possible] plus of the 9"/D44 is that I can pick up a matching set of axles for 500$ or less. Granted I wouldn't gain that much strength over an 8.8 and D35 based on the comparisons you provided, but it would at least be a stronger rear end than the C8.25 and the front would have potential. It would require more fabrication work than than building the 30, but thats the fun part! Also, getting a super 30 kit is around $1000 so I feel like it would be more valuable to spend the money and upgrade the entire axle now rather than throwing money into a D30 that may be replaced down the line anyway. Then again I may just be spewing bs for all I know. Looks like I know what I am spending my night doing. :read::compwork:
 
so what is the width of a '79 Ford f250 D44?
 
Another issue with dealing with the 78/79 Ford HP44 is how are people dealing with the cast part of the Ford mounts? I also was thinking about this swap but keep hearing about staying away from these yrs, but not how to deal with it.

Bill
 
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so what is the width of a '79 Ford f250 D44?

Its 69" and way too wide unless your in the mud... On most tight trails its snug for me and Im at 65"... I disagree with Goat the 30 even with alloys does not compare to the 44 except in ujoint strength even the stock shafts are stronger than the stock 30 stuff(plus I like my 5.38's)... I did the 44 swap on the front and rear and put alloy joints and shafts and Im running with 36's just know that its the limit for the 44 for any sort of durability... as far as a 60 rear not worth the money unless you bore it out to 35 spline shafts and with a nine you need to get the pinion up a bit higher out of the rocks so you dont trash it over and over and that too costs money(big bucks for a high nine center)... To run bigger meats its gonna cost some serious coin just know that now Im into my front and rear for about 2600 including alloys and alloy joints and lunchbox lockers and I did some serious bargin hunting.. I dont have high steer but I did go over the knuckle and my builder axles only cost me 225 to start with so keep that in mind..

Just for reference my rig measures 77" from outside of the tire to outside of the tire
axles= 65"
wheels= 15x8 3.75" backspace
tires 36x13.5x15 SS iroks

so the f-250 starts out at least 4" wider and when ya suck with wheels in with more backspacing you hubs get abused badly... At most I would say I could run is like 4.5" backspacing after that they just stick out too far...

good luck and do a lot more research first it saves untold amounts of money later...


themud
 
Isn't F250 8-lug wheel pattern? What ever it is, if you want to change patterns, you need to change everything, knuckles out.
One good thing about the 250 axle, is it's leaf sprung--no cast radius arm brackets.
 
I understand everybody says a D44 is the same strength as a D30 because the U joints are the same size. It is my belief that because the shafts themselves have a bit more meat around the U Joint that the U joints survive better in a D44. I run the 9-760 joint and did before as well.

I run a 4.7L stroker and have what has been called an agressive driving style. I used to pop D30 axles all the time. Since going with the D44, I have only nuked one hub, and no axles. If anything I drive harder now than before. I still run stock Ford axles. Maybe the difference is that I carry spares :D
 
Wanting to bump this up...

Picking up a set of these for very cheap, and planning to swap em.

Big bearing 31 spline 9"

44 front is cast wedges, but we are going to modify and keep the radius arms.

Planning to have Brandon from Rides duplicate the radius arms he built for this:

http://www.nc4x4.com/forums/showthread.php?t=71712
 
Wanting to bump this up...

Picking up a set of these for very cheap, and planning to swap em.

Big bearing 31 spline 9"

44 front is cast wedges, but we are going to modify and keep the radius arms.

Planning to have Brandon from Rides duplicate the radius arms he built for this:

http://www.nc4x4.com/forums/showthread.php?t=71712

Ford guys like the radius arm F150 axles, but the F250 axles like the OP here mentioned don't have the casting, so they would give you more flexibility. You might look to do a swap with a Ford freak or a Chevy guy doing a Solid axle conversion.
 
Wanting to bump this up...

Picking up a set of these for very cheap, and planning to swap em.

Big bearing 31 spline 9"

44 front is cast wedges, but we are going to modify and keep the radius arms.

Planning to have Brandon from Rides duplicate the radius arms he built for this:

http://www.nc4x4.com/forums/showthread.php?t=71712
I have a 79hp 44 with the cast wedges. I re tubed mine for my application and noticed that the tube going into the housing is only .250" wall. Don't know if you planned on doing a truss but you may want to look into it.
 
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