2nd Gen Non-Engine/Transmission Dana 70 problems

[AClayton]

Yeah..... Thx HB! I saw that last night and talked to him..... Unfortunately, it is a 1st gen 70! We are still researching to see if it will work in my truck.



@D4life- I feel exactly the same way..... a D70 'should' be more than enough for me, but I need to determine whether it is my mechanic that possibly didn't do it right or maybe a faulty bearing. Just don't know at this point until he looks at it. Btw... ... my sig shows about 500hp to the wheels with my power upgrades but I daily drive and tow with only 350hp... ... which has been more than enough! One would speculate that a 70 would be substantial but I guess our trucks just develop so much torque that it brutalizes our drivetrains. I don't dragrace or sled pull or anything..... I do however drive a little briskly at times just because it so much fun. But nothing, IMHO that would otherwise be deadly to the suggested time expectancy of a dana 70!

 

[AClayton]

Yeah..... Thx HB! I saw that last night and talked to him..... Unfortunately, it is a 1st gen 70! We are still researching to see if it will work in my truck.



@D4life- I feel exactly the same way..... a D70 'should' be more than enough for me, but I need to determine whether it is my mechanic that possibly didn't do it right or maybe a faulty bearing. Just don't know at this point until he looks at it. Btw... ... my sig shows about 500hp to the wheels with my power upgrades but I daily drive and tow with only 350hp... ... which has been more than enough! One would speculate that a 70 would be substantial but I guess our trucks just develop so much torque that it brutalizes our drivetrains. I don't dragrace or sled pull or anything..... I do however drive a little briskly at times just because it so much fun. But nothing, IMHO that would otherwise be deadly to the suggested time expectancy of a dana 70!

 

[AClayton]

Yeah..... Thx HB! I saw that last night and talked to him..... Unfortunately, it is a 1st gen 70! We are still researching to see if it will work in my truck.



@D4life- I feel exactly the same way..... a D70 'should' be more than enough for me, but I need to determine whether it is my mechanic that possibly didn't do it right or maybe a faulty bearing. Just don't know at this point until he looks at it. Btw... ... my sig shows about 500hp to the wheels with my power upgrades but I daily drive and tow with only 350hp... ... which has been more than enough! One would speculate that a 70 would be substantial but I guess our trucks just develop so much torque that it brutalizes our drivetrains. I don't dragrace or sled pull or anything..... I do however drive a little briskly at times just because it so much fun. But nothing, IMHO that would otherwise be deadly to the suggested time expectancy of a dana 70!

 

[AClayton]

Yeah..... Thx HB! I saw that last night and talked to him..... Unfortunately, it is a 1st gen 70! We are still researching to see if it will work in my truck.



@D4life- I feel exactly the same way..... a D70 'should' be more than enough for me, but I need to determine whether it is my mechanic that possibly didn't do it right or maybe a faulty bearing. Just don't know at this point until he looks at it. Btw... ... my sig shows about 500hp to the wheels with my power upgrades but I daily drive and tow with only 350hp... ... which has been more than enough! One would speculate that a 70 would be substantial but I guess our trucks just develop so much torque that it brutalizes our drivetrains. I don't dragrace or sled pull or anything..... I do however drive a little briskly at times just because it so much fun. But nothing, IMHO that would otherwise be deadly to the suggested time expectancy of a dana 70!

 

[AClayton]

WTH..... looks like my rear-end isn't the only problem I have this morning! Now my computer appears to be acting up!

 

[JR]

AClayton, do you ever get on CF? They have a large classifieds section I was skimming through a little earlier and saw a handful of rear 70 and 80 axles in either gear choice. The trick would be finding one within a reasonable distance of you but its worth a look if you havent yet, especially if your mechanic has some bad news for you.

 

[AClayton]

AClayton, do you ever get on CF? They have a large classifieds section I was skimming through a little earlier and saw a handful of rear 70 and 80 axles in either gear choice. The trick would be finding one within a reasonable distance of you but its worth a look if you havent yet, especially if your mechanic has some bad news for you.

I found another 70' in good shape on Craigslist..... but don't know whether to get it or wait for an 80. What is CF?

 

[HHhuntitall]

The Dana 70 has a great housing and oiling characteristics, but is has a false pinion support... . Basically translated, it can't take the torque you're putting through it, even at 350hp. I'd wager the inner pinion bearing is out when your mechanic pulls it, or the outer bearing as stated earlier. The 80 is larger, with better supported bearings, and can take the torque much better, although it still will have failure if you load it heavy and put the torque to it. The AAM is a little better, but if it's not a 3/4ton axle, it won't work... . The outer bolt surfaces are just too far out, unless it's a Cab and Chassis axle. And even if it is the right width, you'll have to change your spring hangers, rewelding them back on due to a spring width difference, and I believe you'll have to have the bolts and hardware, as well, as the larger tube diameter won't work with your existing U-bolts and plates..... A Dana 80 is the more viable alternative, IMO.



The 1st gen Dana 70 has even narrower spring pads than yours, so it will work, but you'll have to weld on new spring perch pads..... The 70 was a viable alternative to the more expensive 80, and showed promise when coupled to the Cummins behind an automatic transmission... ... as you'll notice, only auto equipped trucks had the 70. Standards came with the 80... ... Add your built auto behind your twins, and you're transferring a lot of torque to the rear, that it can't handle... ...

 

[AClayton]

I finally found a Dana 80!!! Picking it up tomorrow morning..... it's out of a 97' 2500 5 spd truck and has 160k miles on it. Looks like all it needs is to be cleaned up a bit and new brakes and hardware installed.

 

[HHhuntitall]

ON the yoke, the 70 yoke won't fit the 80. In which case, you'll need either a new driveshaft or adapter U-joint, such as... . (I think this is the right one, just check it out before you buy one, if you decide to go this route... . ) http://www.ringpinion.com/b2c/ProductDetails.aspx?ProdID=10473&Product=DS_U-1435&Brand=Dana_Spicer The adapter U-joint is pretty simple fix-it parts... .



Oh, and SCORE on the good find!! You'll be happier in the end, IMO.

 

[BigPapa]

If I'm not mistaken, which is very possible, the spring pads and possibly the shock mounts will require modification to make the 80 mount where the 70 was.

 

[BigPapa]

This guy on CompD in Northeast Ohio has a rebuilt 70 4. 10 for sale cheap. I think he's down to $300. I just sold my used open 70 3. 54 with almost 400K miles on it for a bit more than that.

http://www.competitiondiesel.com/forums/showthread.php?t=145515

 

[NIsaacs]

I finally found a Dana 80!!! Picking it up tomorrow morning..... it's out of a 97' 2500 5 spd truck and has 160k miles on it. Looks like all it needs is to be cleaned up a bit and new brakes and hardware installed.

Good job! Try and get the u-bolts and mounting hardware, an 80 has 4" axle tubes v/s 3. 5 on the 70. I think the drive shaft will need shortened so you can install a larger yoke on it at that time if need be. I think the shock mounts are the same.



Nick

 

[AClayton]

There is a plethora of information about this swap on TDR as well as other forums. I'm on my way to pick it up now..... it's about a 5hr drive south to Wythville,Va. The seller says it doesn't have any e-brake cables and only 1 drum is good. From what I gathered thus far, a driveshaft mod is necessary, new brake cables, shoes and wheel cylinders.

I may have to just get the 70 back into service while I prepare for the 80 swap.

 

[AClayton]

Can you guys help with a reliable source to purchase the U-bolts and stuff... ... I guess NAPA is the source for the e-brake cables?

 

[HBarlow]

Congratulations. I believe the Dana 80 will provide you years of good service.

 

[AClayton]

Congratulations. I believe the Dana 80 will provide you years of good service.

Thx HB... ... . SEE?????..... sometimes I listen! Lol

 

[HHhuntitall]

I've got U-bolts for stock spring packs, but I'm not sure I have the bottom metal... ... I may can find them in the next few weeks. I've got to hit some yards for spring packs to build up for one of my ranch trucks. Do you have the auxilary springs on top of the main spring pack? 2 or 4 wheel drive? And I may have a set of lower pads, just gotta look. I've had two trucks parted out lately, and I know they both had 80s under them... ... . stuff should be around here somewhere... .

 

[HBarlow]

Thx HB... ... . SEE?????..... sometimes I listen! Lol

Yes, most of the time you eventually do. That's why I like you. You and I have a relationship like a father and son which is appropriate in many ways.

You are often offended, annoyed, maybe even challenged by some of my comments. Your initial reaction is sometimes to reject what I say and stubbornly try to prove me wrong. I'm not always right and you're not always wrong. Sometimes over time you come around and accept that I might have been right after all.

I am old and you are a mature but younger man with less experience. Nature dictates that we occasionally clash. It's just the way life is.

 

[AClayton]

Yes, most of the time you eventually do. That's why I like you. You and I have a relationship like a father and son which is appropriate in many ways.

You are often offended, annoyed, maybe even challenged by some of my comments. Your initial reaction is sometimes to reject what I say and stubbornly try to prove me wrong. I'm not always right and you're not always wrong. Sometimes over time you come around and accept that I might have been right after all.

I am old and you are a mature but younger man with less experience. Nature dictates that we occasionally clash. It's just the way life is.

You are right Harvey... . I am stubborn and hard-headed! It's ok to clash as long as the end result is that everyone remains friends.

The few brake parts that came with my rear are in deplorable condition and all needed to be scrapped. I would assume NAPA is the approved source for all this hardware? What do you guys suggest? The backing plates cleaned up good but I need new drums and EVERYTHING inside them. I found a source online to secure the u bolts and spring plates. Never had a problem with u joints so I may go with the hybrid joint... ... or should I get the bigger yoke and have it welded in place when they shorten my driveshaft?