dodgeguy71

Well, coming home from a job the other day, trailer in tow and all of the sudden, no forward motion. Pulled her back into 4wd and she moved. Looked underneath and driveshaft spinning.

Thought I'd see how many of the 70 miles I could click off before it grenaded. Took off down the road and got 5 miles and it started to squeal so thought it's finished. Pulled off to the side of the road and was engulfed in a cloud of gear oil smoke. Checked under the truck to make sure a fire extinguisher was not required. Closed the door and called a friend at the dealer about a used 3500 axle, called the wrecker service, called the wife, called the junk yard about the axle and ordered it.

Have not looked at the axle yet, but I did park it on a slight slope towards the driver side and it leaked a couple quarts of gear oil out. When we got it on the roll back the driver and I looked at the driver side wheels and wondered why they were **** eye'd. I believe the wheel bearings are fried! New to me differential will be here Wednesday so that evening and Thursday are set aside for replacing the differential. Not sure what happened but have a good idea it's all my fault.

Will try and post up some pictures of the destruction, kinda curious to see if there are any teeth on the ring and pinion.

torquefan

Wow, if that was a dually, it would have been a Dana 80 in there. It's quite the accomplishment to blow one of those up to the point where there's no more forward motion.

rebal

to bad its hard to kill a dana axle I still have my orig. dana 70 with 3:05 and its rolling on to 800,000 miles now,

KATOOM

Dana 80's came in the 2500 manual transmission trucks and all 3500 trucks. Sounds like an issue with the ring or pinion or both. And yes, its hard to hurt a Dana, unless they're completely neglected, but they're still a mechanical device that subject to a bad component.....or was simply assembled on Monday or Friday.

dodgeguy71

Pulled it out today, removed the driver side hub...without unbolting the axle and removing it first! Last time I did this though it seemed like the axle was longer, mine is just a nub, about 2" long off the end plate where it bolts to the hub. Spindle is trashed, nut don't look like a nut. Don't know if it can be repaired as far as the spindle goes. The chunk looked fine, no problems or issues just a busted axle.

Odd thing is I did wheel bearings about 2 years ago, they were pitted in the rollers and the races. I was running Amsoil in the rear as well, changed it about 6 months ago. I know what broke and I know the why. All I can say is that Dana 70 wheel bearings are whimpy, whimpy...whimpy. I've seen true Dana 80 wheel bearings and they are huge. All you guys with the 2500 with the stick shift thinking your rear diff is a Dana 80, think again. Try Dana 80 hybrid, Dana 80 chunk with whimpy Dana 70 wheel bearings and spindles. Your 2500 automatic, full on Dana 70.

The new to me TRUE Dana 80 will be here tomorrow, I hope. Guess the good thing is with the truck broke I can get some things done on the truck and welders!

dodgeguy71

Learned some interesting things today about a 1 ton dana 80 and a 3/4 ton dana 80 hybrid.

Both are 35 spline(2002 models), same chunk from the looks of it, appear to be the same length once you have all the hubs off. I was going to measure them but decided I needed to keep on pluggin' away to get this done. The rotors appear to be the same as well, just mount differently. 3/4 ton you can just remove them, the one ton you need to pull the hub assembly and unbolt the rotor. Side by side though the rotors look identical.

Wheel bearings. I got some wheel bearings at one time that would slide over the spindle(inner bearing), maybe these were 37 spline bearings, not sure. Anyhow, in the end I had a stripped down 3/4 ton axle and used 1 ton bearings laying on the ground with used 3/4 ton bearings. The 1 ton bearings fit perfectly on the 3/4 ton spindle, inner, outer both. The only difference I am seeing is in the inner bearing itself. It has larger rollers, that's it. I guess the only real difference between the dana 80 3/4 ton and 1 ton is the hubs which make it a dually. Maybe the cab and chassis has the 37 spline with larger inner bearings?

Always learning...

KATOOM

So was there any OD difference between the 3/4 and 1 ton bearings? I understood that the 1 ton had different spindles and different bearings than the 3/4 ton but now I cant say whether or not the different spindles are for different bearing sizes or just for the additional hubs.

dodgeguy71

The only difference I've seen Katoom is the inner bearing. It has larger rollers, nearly twice the size of the 3/4 axle inner bearing. It fit the spindle just like the 3/4 bearing.

I ordered bearings years ago online, told them it was a dana 80. When I got the bearings the inner was huge and just fell onto the spindle. That's when I discovered the dana 80 hybrid. I assumed that the difference was the spindle. When I got the new used 3500 pickup axle I thought I'd play around a bit. That's when I discovered the bearings fit, they would swap back and forth between the two.

The only thing I can figure is maybe, just maybe that the cab and chassis rear differential has the larger bearings that I got when I ordered them online. Perhaps that differential is in fact the 37 spline? But the 3/4 and 1 ton both have 35 splines, axles, I'm assuming that the 1 ton is longer but did not measure them. I was in a hurry and they were there but my tape measure was not so I just moved on. Like I said the only difference I've found was the inner bearing. I'll try and get a picture of them today and post it on here.

KATOOM

I am curious to see what they look like since I've always thought that sometimes larger rollers are considered weaker since they place the load over fewer points as where smaller rollers have more points to displace the load. Now wider is different so I'm guessing you're saying that they're the same dimension except the for the rollers.