I just blew my second dana 70 and want to step up to a dana 80. do i need to shorten my driveline or is it a direct swap? i have not found an 80 to buy yet but im looking around.

 

I also busted the teeth off of my 70's pinion and I am keeping a eye for a newer disk Dana 80. Why do these trucks eat Dana 70's? Everyone under the sun says they are bulletproof 1 ton axles but I personally know 3 people other than myself that have also busted the pinion! Let me know how the install goes- your correct about needing the donor trucks drive line or having yours custom shortened.
This video was taken the day the pinion teeth shot out of the diff cover and my learning on these axles began:

 

The Dana 80 is a little bigger so the driveshaft needs to be shortened.

 

just picked up a dana 80 within a two hour drive from home,but has the wrong ratio. im gonna be changing the gears on thursday when the parts come in. i will let you guys know what needs to be done for the correct fit as far as drive line

 

Cool that you found one close by.
Did you grab the u-bolt brackets from the Dana 80 truck as well?
As the axle tube is much bigger.

 

no I didnt, the guy reused the ones he had because he swapped his dana 80 axle out for a 2001 80 with disc brakes. looks like i mite be buying those.

 

got-er done, didnt have to shorten the drive shaft after all. possible because the truck had a 4" lift. everything went smooth the genuine Dana gears and carrier made the set up great and in a timely manor. I ended up buying the u-bolt brackets from the *********** paid $34 each. couldnt find used ones fast enough. the over all size difference of everything from the Dana70 to the Dana80 is amazing, I have no idea why they ever put the Dana70 in these trucks I have found at least 12 people who have whipped out Dana70 rear ends in these trucks.

 

glad it worked, did you need to re-flair the brake lines and did your e-brake setup work?

 

I used the brake lines and e-brake cables that came with the donor rear end, everything was the same except the one line from the frame to the splitter block on the axle housing. that one I had to reuse from my original set up the only difference was my truck has rear ABS and the donor did not. so the fitting on the frame end was different. no big deal tho.

 

nice! sounds like it went better than my drum to disk dana 70 swap did, I have yet to find a way to hook up my E-brake