cumminsdriver635

Well, I have already killed one Dana 70 in my truck. I put another one in it, and it has probably 130-150k miles on it now.

Recently I have noticed that i am getting a lot of noise out of something in the rear. I got under it with a flashlight tonight after i drove the truck about 15 miles, and felt of everything. I have replaced the rear u-joint on the driveshaft once before, but it has just a tiny bit of play in it now.

Under acceleration the rear is pretty quiet for the most part, but when i let off the throttle at 35mph and the rpm's are 1400rpm or so it makes a pretty loud metal on metal sound. Im REALLY hoping it isnt the 70 again. I have an 80 here for it, but i still need to get a couple things, and I really dont have the time to mess with it right now.

The sound sounds like something is spinning very fast at 35mph, so it has to either be the U-Joint or pinion gear. The axles arent spinning fast enough to make this sound. The sound also seems as if it is coming from under the truck more than from inside the axle. The last u-joint on the axle i replaced didnt make near as much noise, but all the needles had fallen out of it. This one im sure still has the needles in it, but they may be grinding bad causing the noise?

I cant shake the pinion shaft at all, and there isnt any more play in the rear end than it ever had it doesent seem. Also, it wasnt hot when i felt of it after the drive. Just slightly warm. My last 70 made no noise when it died, there was just a slight vibration under acceleration and a clicking sound coming out of it which was a broken pinion and ring tooth. This one isnt clicking any, and it is smooth on acceleration. I would think there would be slop in the pinion shaft if the bearings were going and causing the gears to make that much noise.

I am going to grab a u-joint after church tomorrow and hope like heck it fixes it, but anyone want to reassure me its the u-joint?

Thanks

Eric

Diesel_Dan

what about the carrier bearing. I think that you have a two piece driveshaft.

cumminsdriver635

I have a one piece shaft. Found out tonigh that the 70 ate itself. Its still driveable, but it has chunks of metal in it, so im gonna try my best to get my 80 in by this weekend.

kawi600

The metal can be the abs tone ring or something in the clutch pack too, if it has RWAL and limited slip.
When you change the fluid, can you see in behind to the ring and pinion? Maybe enough to inspect for broken teeth.
The spiders would be suspect if this occurred while turning only.

cumminsdriver635

I drove it just a little this morning before i came to class. Heard an awful grinding, and i guess it ate the tone ring because the ABS light came on. This happened on my last D70. I honestly dont care what is wrong with it now. Its coming out tonight, and im gonna round up what i need to put my Dana 80 in it. The D70 has always made a lot of noise when i turn hard though at slow speeds, especially with a load on, so maybe they have been going for a while?

cumminsdriver635

Well, I just spent $590 on a Dana 80 yukon ring and pinion set, and a master rebuild kit with bearings, seals etc. Guess ill have a basically new D80 in it now