Hello, I am a new member being a one week owner of an '05 1500 Hemi quad cab 4x4 with 24k miles. The truck is an off-road package with 3.92's and aftermarket 17" rims and 33x12.5x17 ProComp Mud Terrains. I got the tires balanced and it didn't do much good. It just about rattles the teeth out of my mouth at around 65-70 and smooths out a little past 75. It also hits a harmonic and shakes right at 40mph too. I have been reading some of the forums about tightening the torsion bars to levelwhich causes CV wear leading to shakes.I was wondering a good way to really determine if the previous owner did that. Any advise on vibrations would be a major help.
Thanks.

 

I have/had similar issues with my truck.

Do some searching around here and on another Dodge Forum website - DT.com.

Check your u-joints on your rear driveshaft and your front shaft to see if there is any play in them, replace if you feel any.

Also, check your halfshafts, these come out of your front axle/differential to the wheels. My passenger side halfshaft was toast, I could move it 6 inches in either direction with ease. It's getting replaced today under warranty. The shop that I had install 4.56 gears advised me that the splines were rusted pretty bad but I was hesitant to take it in for fear the dealer would blame that, but if I don't tell, how would they know? LOL

I've also seen/read that motor mounts can cause this too.

Check things yourself if you can to see if you can find the source, then take it into the dealer and have them verify.

 

Yeah, I checked the driveshatfs and the rear was just like new and the front only had about 1/8 in. at the slip-yoke by the transfer case. I'm going to ask the dealer if that would make that much of a difference. The front halfshafts were like new as well, with the only movement coming from in line the splines for suspension travel, only about 1/4 in.
I really think it may be coming from the rear. I looked closely today and noticed the right rear leaf spring looked a bit out of place. The threeplates weren't exactly on top of each other, looks kind of like a set of steps. The other leaf looks normal, one plate on top of the other, maybe the rear end may be out of alignment, although I don't know how one would be off and not the other?

Thanks for the tips.

 

Mine turned out to be the halfshaft and inner spline, all replaced and now she rides smooth as silk again

Yeah, I bet those leaf packs being off isn't helping, did you check the rear u-joints?

 

Does it go away when you let go of the gas? I have the same issue on a 2wd, I reach 65 and its vibrating, at 65 I let go of the gas and no vibration. Step on it again, vibrates. I am taking it in to the stealer. They told me is under warranty.

 

Mine would go down slightly when I let off of the gas, it was just so prominent at those speeds. Not sure what the drivetrain setup is on a 2wd but if you have those shafts or similar up there with CV's in them ... check them out for excessive play.

 

Yeah, the rear u-joints are tight, just like new. I don't know how the rear could have gotten off line, I've never really heard of something like that. The right rear tire is the worst on the truck, I just assumed when I saw it on the lot that they had just rotated the tires and the previous owner didn't align the truck when he put the 33's on it. Turns out now, the rear might be off a little and causing the uneven wear coupled with a vibration. I only got it up to 60 on my test drive and didn't notice anything, now I wish I would've sped with the salesman a little more!! I assumed with only 24k miles nothing would be wrong, my luck, huh.

 

Does your truck have a LSD? I mean have you checked inside the rear pumpkin to make sure that you don't have a loosened LSD clip in there causing problems?

Also, check the seal on the front of the rear diff to be sure it's not shot, I had that problem once causing vibes bad enough to rattle the floor mounted 4x4 shifter.

 

Just a thought, i had a 95 LHS that was doing this and couldn't figure out for the life of me what it was, i finally broke down and took it to my mechanic. Turns out i had a crack in a spark plug wire and it was arcing against the block and that was causing the exact same symptoms your describing

 

You know I forgot to also suggest it could also be motor mounts as well.