2nd Gen Non-Engine/Transmission Project Dana 80!

[AClayton]

My last trip to WVA has reminded me that my Dana 70 rear is just flat out NOT adequate. The mountain grades all but killed my backlash yet again! I made it home with no problem... . but it did loosen up again!



The Dana rear that I acquired a couple of mos. ago is my focus now and I have the disc brake swap complete and ready. I had to pull the hubs and after a couple of internet searches, that proved to be an easy job. There appears to be some controversy, or maybe even a personal preference as to whether or not the axle nut can or should be re-used. Almost 50/50! You guys mind offering your thoughts and expertise once again on this subject?



Alan

 

[NIsaacs]

I almost always re-use mine. What is more important is the little cheap john lock, make sure it is in good shape, (you might have to straighten it before you use it) then make sure you whack it good enough that it gets a good bite in the nylon rim of the nut.

You must have a bad D-70 or set up guy. I have tortured the one in my Ford with no ill effects.

Nick

 

[AClayton]

I have tortured mine for some time now and the mechanic doing the work says the same thing most on here say..... the 70 pinion lacks adequate support when coupled with high torque and heavy loads. Truck has 190k miles on it with roughly 12k of it towing my RV. A huge portion of the remaining mileage is towing a 6k lb enclosed cargo trailer. It is the same old thing though... . the pinion nut loosens. It made to AZ a couple mos back, but towing my RV through the grades of WVA fully loaded caused the pinion to become loose. The ring and pinion have never been replaced, but the carrier and pinion bearings were all done about 3 yrs ago.

 

[GAmes]

I reused mine too, but I have only had them off once for new seals. It never occured to me that they might be one time use only, why would that be?

 

[NIsaacs]

I think it has to do with the nylon locking portion of the nut. As you screw it on and off enough, the built in (nylon) resistance goes away due to it becoming "threaded".



Nick

 

[AClayton]

Does anybody have a part# for the hybrid u joint that I need. The old 70 u joint is 4 1/8 inches wide and the new 80 yoke is 4 1/4 wide. The vendor I used to shorten the rear shaft has no clue what I need.

 

[drag racer]

I recommend NOT re-using the OEM nut and retainer - way too critical of a joint to risk it. Better yet, I would switch to the aftermarket design of double nuts and tanged washers - a much better design and no risk of boogering up the threads - don't ask me how I know.

 

[ata]

Does anybody have a part# for the hybrid u joint that I need. The old 70 u joint is 4 1/8 inches wide and the new 80 yoke is 4 1/4 wide. The vendor I used to shorten the rear shaft has no clue what I need.

Try NAPA I know they sell U-Joints that are one size one way and another the size other way.



I don't reuse the Pinion Nut. Yes it still is tight going back on but not as tight as the first time. Second I have always found that if the pinion nut comes loose it will almost never will stay tight again. (new nut or not) So I never take a chance and just use a new nut everytime.

 

[HHhuntitall]

Does anybody have a part# for the hybrid u joint that I need. The old 70 u joint is 4 1/8 inches wide and the new 80 yoke is 4 1/4 wide. The vendor I used to shorten the rear shaft has no clue what I need.

I believe this is what you're looking for: http://www.ringpinion.com/b2c/Produ...=Rear Diff - 4WD&DiffId=153&Source=DiffWizard



I suggest calling Randy's to make sure it's right by using your measurements before you order it.

 

[AClayton]

Update: I installed the Dana 80 today with no problems. I talked with Nick a few days ago and he confirmed for me that all the joints were the exact same 1410 series from Spicer. Closer inspection revealed that the yoke on the 80 was abused and threw off my measurement. Furthermore, and something I just learned, you don't measure the yoke for it is the actual joint measurement that is important. Anyway, I had Randy's Ring and Pinion overnight a new yoke and my new shaft fit perfectly..... with a new u-joint.

I needed new U bolts, new axle brackets for the 80, and all new brake lines. The disc brake kit from Blackbird installed flawlessly with no problems and all the hardware was complete and cut accurately. I went ahead and ordered a new Pac-Brake air bag kit as my bags were showing their age and looked a little fatigued. I also purchased the brake line that eliminates the Proportioning Valve and added my own manual valve which I procured from Summit Racing. I installed that up front just behind the driver side front wheel for easy access. Not sure if I even needed it but maybe as the pads wear into the rotors a bit, they will become more "grabby".

About the only thing I can complain about is the fact that my 80 did NOT come with a posi-unit. Heavy foot throttle application lights up one tire way too easily and these Michelins are expensive... ... so I either need to slow it down or take out a loan to buy new tires every couple mos. I think I will just slow down until I can get a new Trac-Loc installed!

Thx everybody for all the help and very special thx to Nick for answering my call and few questions! It is very much appreciated!!!



Alan

 

[NIsaacs]

You are welcome Alan, glad I could help. Are you sure the D-80 has an open diff? It might need new clutches.



Nick

 

[AClayton]

You are welcome Alan, glad I could help. Are you sure the D-80 has an open diff? It might need new clutches.

Nick

Unfortunately, it is an open diff... ... has spider gears and when you turn one wheel one way the opposite wheel spins the other way.

 

[HHhuntitall]

Ok, so now I'm curious. How did the 70 have the 1410 U-joints? Is it because it's an '01? I've got three on my yard, and they're all 1350s... ... . but they're older trucks..... Info, please.

 

[AClayton]

Ok, so now I'm curious. How did the 70 have the 1410 U-joints? Is it because it's an '01? I've got three on my yard, and they're all 1350s... ... . but they're older trucks..... Info, please.

The 1350 measures 3 5/8 across... the 1410 reads 4 3/16ths across. The counter salesman kept telling me I should have the 1410 joints no matter whether it had the 70 OR 80 hybrid. Several different sources including Nick told me the same exact thing. It turns out my yoke on the 80 was a bit rounded and measuring it was giving me somewhat of a false reading. It was my original u-joint that was worn a little bit..... the newly installed Spicer 1410 fit perfectly in the new yoke but still a little loose in the old one... but just a little bit. The old yoke probably would have worked regardless according to the guy at Randy's... . he said it was not uncommon to have a little looseness in between the caps. Just make sure to tighten the yoke straps with the caps tight on the u joint. I didn't like that so I had them overnight me a new 1410 yoke.

Alan