Woody

Well, the shake continues. Last Friday I rotated the tires front to back, unbolted the driveshaft from the rear axle, rotated it 180*, and bolted it back up, then I put it back on the ground and checked the pinion angles (which are good). The first test drive after this the shaking was worse, same shake in the rear, seats, and floor... At this point i started thinking that maybe it's possible that the oem tires weren't balanced well and neither were my new ones.. so yesterday I took it to an Autotire that has a Hunter Road Force Balancer and had the rear two tires road force balanced.. The tech said they were "way off" which i'd agree with my seeing that on one wheel I went from a strip of (8) 1/2oz weights down to (2) 1/2oz weights.. The shaking is less pronounced than before, but it's still there, it's basically what it was before I rotated the tires. I'm still at a loss. If it were a bent axle then the rear brakes would be pulsing since the rotor wouldn't be spinning true, same for if there were something keeping the rotor from sitting flush against the end of the axle. So I guess the next step is to pull the driveshaft and get it balanced, which sucks because the only nearby driveshaft shop has M-F hours and I work M-F and have no other vehicle to drive. I may just take a day off, drive up there, remove the DS in the parking lot, and carry it into them if they can check it right then. .

I agree, with the non adjustable 4 link and coils there really is no way to change the rear pinion angle, at least not without buying adjustable control arms or lowering the truck. I still need to crawl under mine and actually check the pinion angle at both ends and see where it's at. Also, to add to this, I have a friend with a 2012 version of the exact same truck as mine, albeit with more miles.. When we park our trucks side by side, mine's a couple inches taller front and rear.. Now I know there were minor changes over the years to the chassis but it had me wondering.....maybe the coil springs are stiffer, making the ride height higher, which would throw off the pinion angle? I mean, I doubt FCA would have changed the 4 rear control arms to account for a little higher ride height.. They probably already had millions of them bought and didn't want to throw them away. . Just more "what ifs" to go with the possibility that it's a pinion angle issue.

I found this thread via a google search. I have the same problem with my 2014 Ram CC 4x4 hemi 8spd with 3.92s. I'm at 33,xxx miles now and have just put up with it until recently, figuring it was the crappy Goodyear SRA tires that it came with. I haven't taken it to a dealer for this issue because the dealers around here are horrible, I treat my warranty as catastrophic failure insurance, if I can fix something myself with minimal time and money and not have to deal with a service department then it helps me keep my sanity. Anyway, the vibration, it occurs at any speed over 60mph and sometimes it's worse than others, it's a vibration in the floor, the seats, and the center console, when it gets bad enough I see the back corners of the bed jiggling. I figured it was the factory tires until I had them replaced a few weeks ago and the problem persisted.. actually the problem got slightly worse because the new tires are of a higher load rating and are running just under 50psi.. Things I've noticed so far; when I towed my boat BEFORE I installed airbags in the rear springs the back end would squat quite a bit, a few inches, and the vibration would go away completely..then with the airbags no longer allowing the rear to squat as much, the vibration came back. It's the same load in both instances, a 6,000lb boat and trailer with roughly 600-700lbs of tongue weight. Since the vibration seemed to disappear when the back end squatted more I am inclined to think that this has something to do with incorrect pinion angle.