rear end swap help...

[F8LDOSE]

Anybody know if a dana 70, or 80 from a 94 and newer will be a bolt in for a 1989? thanks

 

["Mad Max"]

Howdy - the 2nd gen axles should bolt up - I'm 99% positive the perches are the same, but the 80's have a larger housing and I don't think the u-bolts from a 1st gen (dana 70) will clear the 80 housing. There may also be some changes to the emergency brake cables and brake lines. Here's the link to a previous thread that may have some additional info:



https://www.turbodieselregister.com/forums/showthread.php?t=111727



- Sam

 

[RonA]

The housing is larger on the 80 as are the perches. I bought new u-bolts and had to slot the holes on the shock bracket. I also made some shims to match the larger radius on the Dana 80. E-brake cables had to be cut and then spliced back together.

RonA

 

[1stgen4evr]

rear axle swap

This is off subject a bit but is relative to substitution on the rear axle.



I have known for some time that there are dana 70 HD axles that were in some Chevy "camper specials" from a few years back. These are dually width and can be used on our trucks with a bit of modification.



What are the benefits of doing a 'hard' swap as opposed to a 'bolt in' with this? Well I want the larger brakes which are 13 by 3 1/2. The tubes on these axles are bigger than our first gen 70s and if memory serves me correctly, there is a larger pinion bearing set and maybe larger carrier bearings. The hub bearings are larger and again from memory, I think the drive axles are slightly stouter. For this particular swap, I got this axle really cheap. That may be the case in other places as there are few calls for this particular axle.



I have recently acquired one and will be making the changes to use it in one of my trucks. I am sure the e-brake is slightly different and I will have to get the correct yoke for the drive shaft hook up. The lugs are different and I think will require the newer hub centric style Dodge wheel. I believe that I can use the footed lug nut that Ford uses which I have had very good result with. The spring perches/pads are not in the correct placment for a Dodge but I have changed those on other axles with good success. I bought the axle with a short section of frame which has the heavy sway bar that is typical of the Chevy setup. I will incorporate that into the refit of this to my truck. The larger ubolts are on the axle so I won't have to buy new ones.



I will do a follow up on this when I have more exact info. Anyone who can contribute on this, I would appreciated the advise.



1stgen4evr

James



It is my position that any modification to a first gen is allowable without penalty from higher powers if it is performed by the owner and thus will not render the truck a misfit in the first gen section. This includes parts borrowed from Ford, Chevy, GMC or the space shuttle which in the analysis of the owner will make the truck more powerful or allow continued operation at less expense. (more powerful, less expense--- how is that for complete opposites) Actually I am going for continued operation. Easing up on 440k miles with the manual 93.

 

[NIsaacs]

The Chevy Dana 70HD will fit Ford's too I have one in my "74" F-350. Like James said they have some major benefits over the standard dana 70. Depending on the year & model they are out of, and the year & model they are installed in, you may or may not have to change spring mounts. Mine was a direct bolt in other than the drive shaft, the chevy uses a bigger u-joint than the Ford. They have 4" axle tubes like the dana 80, so I had to enlarge the u-bolt circle. The Dana 70HD is rated at 10,000lbs weight capacity, and 8800 ft. lbs. of max torque, the 2000 ft. lbs continuous torque is the same. I think the pinion brg. set is the same on both units, however the carrier brg's. have a larger outside diameter. The Dana 70HD is good stuff, almost as good as the 80, and a whole lot cheaper





"NICK"