bent axle

[DDGETHS]

How do I tell if I have a bent or warped axle? I get this vibrations when acclerating at 40 and when braking at 40mph. It is only at 40 though. I have recently replaced front hubs/bearing, all the u joints, had my driveshaft rebalanced. tires balanced. Now what should I do. Someone suggested that I replace the ball joints but I don't feel it in the steering wheel it is in the seat like it is from the rear. I do have a seal leaking on the drivers side rear axle. Thanks for the help.. Pete

[steved]

Could be the leak is causing the rear brakes to hang up some...but this usually happens when you step on the brake.

Could be that the leak is being caused by a bad axle bearing in the rear?? But you should have a noise (I would think). My pinion bearings went bad (they were noisy too), but they got bad enough before I fixed it that the truck would vibrate cause the pinion/ringgear were getting out of sychro.

Are your pinion angles right...I don't know much about it, but that'll cause vibrations. Someone here will know more about it.

steved

[DDGETHS]

I could see how it would be the brake getting hung up on the oil when I brake. But it will happen when I drive at 40 but does get worse when I apply the brake. Pinion angle should be fine. But it could be the pinion bearing. I'll have to try changing both the pinion bearing and the axle bearing so see if that fixes it.. Thanks Pete

[GRMhick]

Sometimes the seal can leak because of a bent housing. or it could be the rear axle bearing is worn out allowing the axle to move in the housing, causing the vibration, and allowing the diff fluid to leak out.
Have you pulled out the shaft, and checked it out to see exactally where it is leaking from? The races on the shaft may be worn out too.

Garrett

[tv_larsen]

It's sounds very likely that the leaking seal soaking the brakes could be causing it like steved suggested. I'd fix the seal (and brakes if they're oil soaked), inspect the bearings and races, then see if the vibration continues.

It seems that many of these newer Dodges have somewhat of a rear end vibration. My '99 does it very slightly at about 40mph in OD, but a slight speed change, or downshifting makes it go away. It never does it braking however.

I believe that, for most trucks, this (usually mild) vibration is a result of natural harmonics. The combination of tire pressures, tire balance, long soft springs, engine rpm, and normal frame flex result in a building natural frequency vibration. The Club Cab/Quad Cab short bed 1/2 tons usually seem to have the worst vibration.

For more info:
http://www.dodgetrucks.org/forums/viewtopic.php?t=12107

Also a chart that might help:
http://www.imagestation.com/picture/sraid23/pbe29f0636deb753c4d2a0a75bff64dc2/fda21c06.jpg

[GRMhick]

Wow, excellent info. I am still trying to track down some wierd vibe in my ram, that is almost completely random, and I feel from the speeds of 55-80+.