So I am having very bad shaking in the rear between 55-75mph. If i have a trailer on the truck in is really bad at 55mph. Had tires rebalanced and rotated and still doing it so it is not tires. Driveshaft is tight and no play. Wheel bearings are good. Have had it in to dodge where i bought it and to my mechanic and no one can find anything wrong. Curves on highway will set it off and cause it to shake really bad too. Dad and I got under the truck and noticed that I have an aluminum drive shaft (5in diameter) made by Spicer. It looks brand new and still has the p/n and lot number tag on it in perfect condition. Is that the stock drive shaft that dodge uses, or has it been replaced? Any help would be great. Thanks

 

2wd uses aluminum shaft whereas 4wd has a heavier steel shaft.

Maybe the rotors are warped?

 

Bad rear shocks? Bent rim?

 

I vote BENT driveshaft. A few guys have actually twisted the aluminum in half. If you have a driveline shop nearby, take it to them and get it checked out-----seriously

 

Ok I will have to do that. Is there a possibility that it could be the gears in the differential? I have read some stuff online with guys having the same problem and they replaced everything in rear end including axles and that finally stopped it. I talked to a driveline shop yesterday, I just need to find a day I can take it in.

 

Do you have 4.56 gears? What is your engine RPM when you feel the shake?

 

Does it also come with a howling noise too? That happened to me, even bought new tires. Same problem. Ended up being the pinion bearing in the rear diff.

It would happen at all speeds and conditions if it was in the drive shaft. If it is just under engine load at reasonable speeds...45+ (put the truck in neutral and coast) I would point to a bearing in the rear diff.