2015 Ram 1500 Rear wheel shake / wobble
 

Hey all,

So for quite some time now I have had a shake/wobble/bounce coming from the rear end ever since I switched out the tires to real truck tires. I have had Dodge thoroughly inspect the truck, I have had a front wheel alignment (wasnt out to begin with), I have tried 3 different sets of brand new tires, and 3 different sets of rims! I have set up a stand and measured run out on the rims, then the rotors, and the hubs. All of which were out quite a bit. Found the hubs themselves were out 0.010" and 0.008". Send my local Ram dealer videos of this, and after them running the same tests and getting the same measurements, they replaced both axles under warranty as the allowable run out is only 0.005. Got the truck back (Brand new BF Goodrich KO2's, and brand new Fuel rims), and NOTHING has changed! I removed wheels, rotors, and remeasured run out on new axles, and found only 0.004" so I am happy with these measurements. If I tilt my mirrors down so I can watch the tires while cruising down the highway, I can actually see the wheels start to shake side to side on and off (not constant but about ever 8 seconds it starts and stops after about 5 seconds and continues doing this as long as I keep driving). The wheels dont look like they are bouncing up and down, but I wonder if they are and it appears to be side to side due to the tire shape/compression and making it look as though it is wobbling side to side. Anyway, my new Monroe Reflex shocks for the rear will be here tomorrow and I will install them, however, I doubt this is the issue. Any help would be greatly appreciated!

P.S. My truck is the Limited Edition, stock height, with 4 wheel factory air ride suspension.

How are your u-joints?

As far as I know they are ok. I jacked up the back end and grab the wheels trying to pull/push to see if I can feel play in them and they seem solid.

I was thinking ball joints... Ujoints seem nice and solid as well. I’ve had bad ujoints previously on a different truck and that feeling was more like a hard vibration versus a wobble/shake.

maybe a balancing weight fell off the driveshaft.

I don't think there are any ball joints out back...... :)

remove the driveshaft and move the ujoints by hand. when its bolted up you will only find ujoints that are ready to fall out...tight/dry seized/ roughness would be missed.

if you still can't isolate it. Find a dealership with a vibration analyzer. Once the frequency of the vibration is measured...it will give you a clue to the part that is causing it. Wheels, tires and axles rotate at one frequency range...driveshafts another.

Thanks for the input.