decode this axle!
Elder User
Joined: Jan 2010
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From: Hattiesburg, MS
That only applies to F-250 4x4's. ALL F-350 2wd trucks are narrow frame. 79 F-350 4x4's are wide frame.....except for chassis cab models.
Elder User
Joined: Jan 2010
Posts: 787
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From: Hattiesburg, MS
.....unfortunately, it's not that simple. The tubes taper from 3.5 inches to only 3 inches. Right in the middle of this taper is where your new spring perch will be.
But, I'm getting ahead of myself. The first thing you have to do is remove the drum brakes. Then fab or adapt caliper brackets. There are no "bolt-on" disk brake kits for this axle.
After you get the brakes removed, you can worry about the perches. (you have to remove the brakes first because your springs will not fit between them). You can either get creative with your welding.....and put the perch right in the taper. This will require 2 different size u-bolts and a custom top plate. Or, you can find a short section of 3.5 inch tube and "sleeve" it.
I know how much you value my opinion.......but if you haven't bought this axle already, I would pass. You can make it work. But, unless it's just dirt cheap, there are other axles that require much less work.
But, I'm getting ahead of myself. The first thing you have to do is remove the drum brakes. Then fab or adapt caliper brackets. There are no "bolt-on" disk brake kits for this axle.
After you get the brakes removed, you can worry about the perches. (you have to remove the brakes first because your springs will not fit between them). You can either get creative with your welding.....and put the perch right in the taper. This will require 2 different size u-bolts and a custom top plate. Or, you can find a short section of 3.5 inch tube and "sleeve" it.
I know how much you value my opinion.......but if you haven't bought this axle already, I would pass. You can make it work. But, unless it's just dirt cheap, there are other axles that require much less work.
Tuned
Joined: Jul 2001
Posts: 439
Likes: 0
From: Erie, Pa
Hillbilly, just in case you are wondering, this axle came from a 1978 Ford F-350 that was single rear wheel, and had a style side bed. The frame rails were 37" wide (same as all ford trucks of 1978-1979). This was not a cab chassis. This was in fact a Crew cab long bed pickup. There were no special wheels, or spacers used in order to install standard Ford steel wheels on this axle. I have a dually Dana 70 rear axle, and the WMS is not as wide as this axle. This WMS and spring pad distance is the same as a Dana 60 from a F-250 of the same year (as I have 2 of those sitting here also).
Steve S.
To many to list.
Steve S.
To many to list.
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Elder User
Joined: Jan 2010
Posts: 787
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From: Hattiesburg, MS
Well, BOM says: 603896 - 70 - Rear - 1978 F-350 1-Ton Pickup, Dual Wheel & Other - 1 Piece Case.
Maybe there is an error with the BOM?? Either way, I'm only working off the number.....since that was the only information provided. If you know so much about this axle already.....then why does your friend need it "decoded"?
The reason there were no special wheels or adapters....is because they are not needed. Even the F-350 SRW pickups use a "DRW axle". You can bolt on singles OR duals......does not matter. And, no, all 78-79 trucks were NOT wide frame.
I wanna see some pics. I was under the impression there were NO SRW Dana 70's made until 80. I'm hoping you can prove me wrong.
Maybe there is an error with the BOM?? Either way, I'm only working off the number.....since that was the only information provided. If you know so much about this axle already.....then why does your friend need it "decoded"?
The reason there were no special wheels or adapters....is because they are not needed. Even the F-350 SRW pickups use a "DRW axle". You can bolt on singles OR duals......does not matter. And, no, all 78-79 trucks were NOT wide frame.
I wanna see some pics. I was under the impression there were NO SRW Dana 70's made until 80. I'm hoping you can prove me wrong.
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Elder User
Joined: Jan 2010
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From: Hattiesburg, MS
Well, the best I can tell (looking at it from the tiny screen on my cell phone) it has all the signs of a narrow frame axle. Meaning it has the narrow cast iron spring pads and the shocks bolt to the sway bar mount. Do the tubes neck down Just before the backing plates? I can't tell from the pic. Also can't see the drums very well, but they look like drw drums.
Elder User
Joined: Jan 2010
Posts: 787
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From: Hattiesburg, MS
Well, yours is upside down and covered in dust.....but it looks just like one of my 70's
If it's like mine, I can assure you it's a narrow frame axle.
Here's a closeup of the tube:
Right in the middle of that taper is where your spring pad will need to be. Notice the cast iron spring pads with the tapered ends. Only the narrow frame axles with the 2.25" springs use this style pad. The 70's with 3" springs also use a cast pad. However, they are shaped different.
If it's like mine, I can assure you it's a narrow frame axle.
Here's a closeup of the tube:
Right in the middle of that taper is where your spring pad will need to be. Notice the cast iron spring pads with the tapered ends. Only the narrow frame axles with the 2.25" springs use this style pad. The 70's with 3" springs also use a cast pad. However, they are shaped different.
Tuned
Joined: Jul 2001
Posts: 439
Likes: 0
From: Erie, Pa
Well Hillbilly, I must eat my crow and appologize here. I took measurement from the cab chassis dually Dana 70 and this Dana 70 and they are exactly the same. I did not think that there were any narrow frame trucks after early 1977. This would make that bed (if it was any good) a very rare bed then (narrow frame mounting, dual fuel doors, with race track trim).
Again, I am sorry I spoke up about this, and I now have to go change my add.
Thanks
Steve S.
To many to list.
Again, I am sorry I spoke up about this, and I now have to go change my add.
Thanks
Steve S.
To many to list.
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