Dana 80 Swap

[Shadrach]

Has anyone swapped in a Dana 80 in place of the 70 in a 1st gen? My buddy blew up his 70 again :{. Too much weight and torque I guess. Shadrach

 

[Simplysmn]

If I had to do it again I would swap a corp 14 bolt out of a chevy Pretty stout rearend if ya ask me .

 

[RSchwarzli]

Yes, I did it on the crew. Granted, it might not work the same in the sense that I went to aor ride at the same time but...



What do you want to know?

 

[Shadrach]

What did you have to change to mount it? Driveshaft length? Spring saddles? Shock mounts I know are different. He will want to stay with leaf springs and drum brakes. How many different widths are there? His truck is a dually. Shadrach

 

[RSchwarzli]

Yes, pinion length was different so driveshaft did change.



Shock mount are also different.



Widths, there are three used in Dodge trucks if my memory serves. Wide to narrow: Dana 80 dually 3500, Dana 80 chassis cab dually 3500, Dana 80 2500.



If he wants to stay drum, then it is a pre 2000 axle (hope I remember that year right) as they went to disks then till the end of the 2nd gen run. Also remember that when they went to disks they also did a ratio change from 3. 54 matching our first gens, to a 3. 55 ratio.



As for the springs, cant answer that as I do not have any leafs at all. I changed to a 4 link air ride so I am not 100% sure.



Hope that helps!

 

[HHhuntitall]

Widths, there are three used in Dodge trucks if my memory serves. Wide to narrow: Dana 80 dually 3500, Dana 80 chassis cab dually 3500, Dana 80 2500.



If he wants to stay drum, then it is a pre 2000 axle (hope I remember that year right) as they went to disks then till the end of the 2nd gen run. Also remember that when they went to disks they also did a ratio change from 3. 54 matching our first gens, to a 3. 55 ratio.



As for the springs, cant answer that as I do not have any leafs at all. I changed to a 4 link air ride so I am not 100% sure.



Hope that helps!

First off, I really need to see your 4 link system at work. That's just downright cool! I've been wanting to monoleaf the front and airbag my '90! Nothing like spare time, right?





I believe there are only two frame widths, as the Regular Dually(non-CC) will bolt right under a 3/4 frame; the CC is narrower. The springs will have some differences. The early CC springs had bolt eyes that both curled up, while the 3/4 and 1 ton trucks had one turned up on the front, and one down on the rear. That was up to '97; I'm not sure if that carried all the way through the CabChassis line run. As far as the brakes, it depended on the build date, location, and what was in stock!! I believe all the 4x4 built after Dec? '99 had disk brakes, but I've seen some later '00s that had drums in the 2x4 3500 trucks. You'll have to mount new spring perches on your axles to mount it under your truck. The lower shock mounts we cut off carefully, moved in, and rewelded to match the factory shocks on the '93, even on the CC axles. As far as the gear ratio difference, you can get away with it on dirt, but don't dare ask much on hard surfaces(duh, right?). The older Fords had 3. 54 rears and 3. 55 fronts in some instances from the factory. Locking hubs are your friend!

 

[RSchwarzli]

Will see what I can do in regards to pics for you!

 

[Shadrach]

Thanks guys. Shocks mounts and leaf saddles I had fiigured out and modifing the drive shaft length is no problem. What about the ujoint? Is it a different style? Shadrach

 

[HHhuntitall]

Shadrach,

Uhhhhh, I THINK the standards were the same. I know the autos were smaller on most of the old 250s, but on the 350, I'm not sure... ... . I know my '93 has the same u-joint as my '97, so I'm betting you do. Just watch out for variations in make and model!!



And what's your four door, and how much do you want for it, if it's still for sell?



BSchwarzli,



Pics would be greatly appreciated. I've done airbags on some large fords and such, but they weren't very practical. I'm curious as to what bags you used and how much travel you have with the 4 link setup?



Thanks,



God bless,



Casey

 

[Shadrach]

What about rims? Will the 93 style dually rims fit on a Dana 80? It would be a pain for rotating with different rims front and rear. Shadrach

 

[RSchwarzli]

No they will not. I tried!



Goes like this:



Rear is a hub centric design with 5/8 studs. Front is a stud centric deisgn with 3/4" studs. There is therefore a diameter difference between the front and rear hub cutout of the rim. Therfore, will not fit. Only option you have is to mill a front hub bigger and then a front should fit however the studs will be sloppy. Could solve the play with a cone nut type of thing... .



Sorry to be the bearer of bad news.

 

[Shadrach]

So What do you have on the front of your truck for rims Robert? Shadrach

 

[HHhuntitall]

American Eagle Alloys sells an American made aluminum dually wheel that uses Mag-type lugnuts. They have a shank that goes down into the wheel, with a washer under the lugnut head. My '90, '91 and '93 all have 5/8 lugs all the way around. But, if you switch the axles, you can buy a different set of lugnuts, 16 5/8, and 16 9/16, but externally they'll all look the same. On the last one we did, we swapped Chevy dually hubs up front, and they had 9/16 lugs..... just an idea. You could then use the '94 up dodge wheels... .

 

[RSchwarzli]

HH is correct. I screwed up on my memory! The fronts are 5/8 rear are 9/16. Me so sorry!



As for mine, I still have not 100% decided. As that will be the last part I will need before I start driving...



My current thought is to use a cone nut that goes into the wheel. Would have to do a 5/8 stud on all rims, but would need the ID of the 2nd gen rim (as it is hub centric). All I really know so far is it will be a 19. 5...



As for the front hub off a chev, interesting. Love the idea, not sure I can put a chev part on my Dodge though!



EDIT: Thinking here, as the 1st gen front rim is a stud centric design, you would not have the support/strength on using a 9/16 stud and not haveing it ride on the hub, unless that chev hub was also a hub centric design that matched the Dodge rims hub ID.

 

[Midnite]

Why mess around? If he's repeatedly blowing up Dana 70s then maybe he should step up to a Rockwell 2 1/2 ton. I didn't think the D80 was that much bigger and stronger than the D70, but maybe I'm wrong.

Mike

 

[HHhuntitall]

As for the front hub off a chev, interesting. Love the idea, not sure I can put a chev part on my Dodge though!



EDIT: Thinking here, as the 1st gen front rim is a stud centric design, you would not have the support/strength on using a 9/16 stud and not haveing it ride on the hub, unless that chev hub was also a hub centric design that matched the Dodge rims hub ID.

As far as a Chevy part, just think DANA... . that'll make it easier. But if you go that route, it'll depend on what brake rotor you have, you may have to get new ones. Some are too thick to accomodate the factory Dodge pads inside the calipers.



I used Alcoa Aluminums on my '93, and if I remember right, they were hub centered. Hmm, I'll have to check that. I know the rear were, as I used drilled '01 steel rims on the rear(the lug holes had to be drilled). I drilled the Alcoa's, too, so I could use the American Eagle Lugnuts in 5/8. In '01, Alcoa offered a rim setup that mirrored Dodge's increased 1/2in of backspace so you can use a larger tire. I filled the extra 1" of space with 255/85R16s. Depending on brand, they usually only touch when loaded really heavy.



What's the bore on Dodge wheels, 4. 88? I think Fords are 5. 13 or so. Same as Dexter/Hayes 12,000 lb tandem dual axle.



I'll get back to you guys.



God bless,

 

[Cumminsduallyguy04]

What did you have to change to mount it? Driveshaft length? Spring saddles? Shock mounts I know are different. He will want to stay with leaf springs and drum brakes. How many different widths are there? His truck is a dually. Shadrach

In case your still interested Im swaping a GM 14 bolt 10. 5 rear into a 91 dodge as we speak. I scored the gm rear for $50 courtesy of cash for clunkers. It has 15" drums compared to dana 70U 14inchers. the swap appears to be simple at this moment. Cut all brackets from 14 bolt make new (im on a budget too many projects started) leaf spring perches. weld them on and bolt the rearend back into the truck. Im satisfied with the gear ratio at this time. When budget allows Im gonna throw in around a 3. 50:1 gearseat and spool. In the summer time we convoy at 100+ mph to my bonfires. As far as driveshafts are concerned on a budget im going to source the 2nd peice of a 80's 3/4 ton suburban rear driveline. I will have it cut to length at a local truck shop and mated to the dodge 2 peice driveline and balanced as a assembly. I havent measured to see if it will work but I will do a thread soon on the swap. the 10. 5" 14 bolt rear has a much shorter pinion than the dana 70U. as far as parking brakes are concerned i grabbed the rear half of the suburbans parking brake cable setup and kept the cables and brackets from the suburban.

 

[Cumminsduallyguy04]

Thanks guys. Shocks mounts and leaf saddles I had fiigured out and modifing the drive shaft length is no problem. What about the ujoint? Is it a different style? Shadrach

u joints between 80's 3/4ton suburban gm 10. 5" ring gear 14 bolt and dana 70U are the same in my 91 dodge 250.

 

[Shadrach]

I still haven't figured out the rim problem. Any further ideas? Don't forget this is a dually. He wants to be able to rotate tires and only carry 1 spare. Shadrach

 

[RSchwarzli]

Was speaking with Rickson wheels. They will custom do what I need for mine. The larger hub so it works on both, and will also put the larger 5/8 holes. For the rear with the smaller holes, they will supply tapered cone nuts so there is no movement.



1 rim. Works all the way around.