busted ring and pinion
 

About a year ago I was pulling out a small shrub oak at my house on dry dirt, stock michelin tires, no positraction, and there was a loud pop and some big clunking sounds. put it into 2wd and everything was ok wouldn't get back into 4wd. Since the truck is on blocks with tranny out I opened the front diff to look and I am missing about 5 teeth on the ring gear an the pinion is damaged too.

Has anyone else had this happen, it makes me worry about the durability of the front diff with power mods later on?


pacmule

That is VERY unusual. The front end wasnt on blacktop while the rear end was on grass was it?

The Dana 60 front ends in these trucks very rarely break.

My cousin has been pulling his 600hp cummins for 3 years now. He swapped to different gears this winter, but he never had a problem with the stock 3:54 gears in the front differential, and the differential has 230k miles on it.

Most other guys i know that pull havent had to touch their either. Sounds to me like you just either had some bad luck on that one, or the front end was on a really sticky surface with no give and the rear was on something loose, so the front end had to soak up all the power.

I have 240k on mine now and it has never been touched either. I pull with it some, run it down the drag strip and do launched in 4wd some, daily drive it, and use 4wd out on the farm hauling hay and things. No problems yet.

Eric

That was what I was thinking Cumminsdriver. I know that guys are pulling with these things using twice the power I am at now. I was on dry dirt at the time, all four wheels spun a little and were digging in, I think there must of been a weak spot in that ring gear since day one and I just put enogh torque to it to make it snap

pacmule

I think you are right. It must have already been about to break, or cracked before, and you were the lucky one to finish it off! [laugh]

Eric

I snapped my rear pin. shaft off right behind the yoke!! That sure was expensive...

Dana 70's are no fun.

I killed 2 of them. I have a Dana 80 now, and im not worried about the ring and pinion in them, but the spiders are the weak link. Hopefully i can keep from busting them no more than i pull though.

Eric

Any fluid left in there?

The axle seals can leak, especially if driven in sandy conditions or if the breather is blocked... low gear oil can allow the teeth to heat-stress.

XLR8R, yes there was plenty of fluid in there when I opened it up.

pacmule