Rear axle strength for sled pulling...
 

I was running a rear 70HD on my pulling truck. At my last pull, right before the 300' mark, I ended up twisting off the pinion gear right at the end of the yoke. I'm planning to upgrade and thinking about a Dana 80. I've located an 80 out of an E350 with 35 spline 1.5" diameter axle shafts. Are any of you guys breaking gears or shafts on the Dana 80's with 35 spline (1.5" shafts) or 37 spline (1.6" shafts)? Is anyone running upgraded / aftermarket shafts in their 80? -thanks-

I dont know about the 80 but a good friend of mine had the same problem with his 70. Except his put a hole in the bottom of the axle casing the size of my fist.

Yea, at least my housing was still useable. Just took out the gears and gouged up the bearings.

Are the guys without rear end problems running Sterling 10.5's, Dana 80's or something else? Open, welded, limited slips, or lockers? -thanks-

Dana 80 is the way to go... Cheaper route is a gm 14 bolt.

The problem one of my friends had with a stock Dana 80 was twisting the axils out of it. Aftermarket axil seem to have solved the problem for now. GM 14 bolt is super strong also.

14 bolt axles aren't as strong as an 80 but the 80 has a weak pinion yoke in comparison IMO. Seen two of those break off, one damaging the pinion gear, never seen a 14 bolt break a pinion yoke. Never seen a sterling break the gears...axles though will break. I personally would rather break a shaft than anything else in there, but ideally of course would like to break nothing. Could always upgrade to militarys :)

stock 35 spline 80 will befine know many poeple i pull with running them behind big torque cummings and one 900 ft lbs 6.0

I run a 14 bolt in my stock pulling truck. Never have had a problem. It was in the truck when I got it. The PO said he was breaking 70s all the time. 14bolts have gotten so cheap around here[200 to 300 bucks] they just seem a good option.

Sterling 10.5 with stock ford limited slip and stock shafts. Welded axle tubes. So far so good.