I'm about to really start pulling my hair out here. For the past several MONTHS I have been chasing a vibration in my truck. It can be sort of described as a "bouncing vibration" that occurs at all speeds, but is the worst while cruising on the highway above 55mph. If I have the cruise control set and I'm on a nice, smooth road the whole truck will get into what seems like a harmonic vibration that shakes everything. It almost feels like tiny little bumps in the road, but it does it even on perfectly smooth, freshly paved roads. It is much worse while towing, even an empty trailer. This started a while back after I had installed the leveling kit and the 2" rear blocks. I have tried anything and everything I can to eliminate it, but nothing seems to help. Here is what I have tried so far:

- Rear driveshaft replaced by dealer
- Adjusted toe
- Removed front driveshaft
- Adjusted front caster front AND back
- Added Dynabeads to all tires (8oz balancing media)
- Rotated tires
- Removed rear blocks
- Rotated tires again
- Installed Bilstein 5100s
- Removed REAR driveshaft (drove with only front in - yes I capped the Tcase)
- Removed front leveling spacer
- Checked balljoints with dial-indicator
- Swapped in a know-good set of stock tires

So other than the shocks and tires, the truck is now on 100% stock suspension. Everything seems tight and nothing LOOKS out of wack. I even coasted down a hill with the engine OFF and I can still feel it. I'm leary about taking it to the dealer again because they don't seem to give a crap, but it looks like I might have to leave it with them and demand they fix it right. Last time I don't even think they test drove it following the driveshaft replacement.

So, does anyone have ANY more ideas for me? I am completely stumped on this one. I can't think of anything else to try. Any and all opinions are welcome.

 

Wow, you have a real problem there, I had a vibration in mine at one point, but it ended up being a u-joint. But I would say you have that covered, unless it is a ujoint in the front??

Just a thought

Kevin

 

I have a similar truck to yours except it has a long bed. I had a similar problem to yours except mine got worse rear quickly. Mine ended up being bad u-joints in the drive shaft. I replaced all 3 as well as the hanger bearing because the driveshaft vibration tore it up.

You say you replaced the drive shaft but I'm noy sure if the u-joints all got replaced as well. To help diagnose my problem we jacked the rear off the ground and put it in gear and ran it. That helped us narrow down the problem.

 

my 04 2500 std cab long bed 4x4 does it at speeds above 60 mph. It doesn't vibrate the truck, and it only does it when you hit a small pot whole or bump, especially on the interstate. It shakes the **** out of the front of my truck. I can slow to around 30 mph and it quits. Got better when I replaced the shocks but I'm wondering if it's not the spacers on top of my coil springs causing it.

 

You're talking about 2 seperate issues you have the dreaded death wobble do a search and you can read for days.

 

I'm with Kevin, do you think it might be a bad front Axle u-joint?????

 

I don't think so, because it does it while going perfectly straight, but it could be a possibility. I don't know how I'm going to check them though, without pulling the bearings and the shafts themselves (no thanks!). I have jacked up the rear end and run it in gear. The first driveshaft noticably went up and down, but I haven't done this for the second DS. I think I might put the whole truck up on jackstands and run it in gear in 4WD to get all tires spinning and see if I can't see/hear/feel something. It'll be the end of week before I have time though.

Townsend600 - Your problem really does sound like "death wobble", if it only does it over bumps and gets worse until you slow down (does it?). My problem is definately not that.

This is bad enough for me though that I am considering trading in the darn truck and starting fresh. Really sucks because I am DEFINATELY going to take a hit finance wise. I'm just cresting that "you owe as much as it is worth private party" right now, so I'll get killed on a trade-in.

 

townsend, bring your truck in to a good wheel alignment shop, have them advance your camber to the max that they can, should either remove or greatly diminish your problem.

As for yours 4x4,, I would change every ujoint on your truck,, not overly expensive, and I have a fair ammount of confidence it should fix your problem..... mine was one of the rear u-joints, but it just as well could be one of the front ones, it might not even be the knuckle ones,, but I think the front driveshaft could even do it,, for the 30 bucks for the ujoints on it I would do it

Kevin

 

I vote again for driveshaft ujoints. Mine all seemed to turn fine on the truck, but when I took of the shaft you could tell they were'nt any good. I had someone put in new joints for me. They said 2 of the 3 didn't even have any needle bearings left just dust. I only replaced the ujoints on the rear drive shaft but it vibrated everything from the rear diff to the transfer case.

 

If you had access to a dyno or something like that, you might at least be able to see if it's the rear (if it's not, you know it's in the front). Like others stated, maybe it's a bad carrier bearing (long beds)

On my old 98 dodge, I had a set of cheap drums put on and they caused a bad vibration, took a while till dodge said they were out of balance (not many places know if there out of balance). Other than that, my only guess would be maybe something in ternal (like a spyder gear fell outa the carrier housing) or a chiped gear in the t-case. Some of the stuff will drive you nuts.

I had a 86 bronco, had a very bad knock on side to side turns, I replaced everyting. Turns out the bolt was bad in the rear leaf spring Some of the oddest things cause the most common issues.

 

I still think it is a bad Axle u-joint, it does not matter if your going straight or turning they can still cause vibes! If you took out the drivelines front and rear like you said and you still have the vibe then my guess is still the front axle u-joints. you can check them to see if they are loose by moving the u-joint with a pry-bar or even your hand, if you see any movement then that joint is bad.(you don't have to tear the front end apart to check them for looseness)



If hes taken the drivelines out and test drove it like he stated in the first post then it could NOT be the driveline joint's
plus the rear D-line is brand new!!

 

I agree it has to be in the front, my ujoint wasnt loose, it just kinda froze up, weirdest way too. The dealer though said that they had a few that it happened too.

Kevin

 

I have had bad U-joints in the front axle shafts on my Jeep and it didn't cause vibration like this, but who knows. That Jeep shakes, rattles, and rolls! I guess I'll stick a prybar on them too when I start more testing on Thursday. But I'm working 4 more 12 hour days so I won't have any daylight until then. Hopefully the weather plays nice. BTW, I KNOW it isn't the front driveshaft 100%, and I'm about 99% sure it isn't the rear. They replaced everything on the rear shaft, including the yoke and balancer.

Thanks for the ideas so far, keep 'em coming!

 

So you did drive it with the rear driveshaft completely disconnected right??

 

Yup. Didn't get it up to highway speeds, but I did hit 40mph and it still felt the same.