StevenAg03

Over the past couple weeks I have noticed that my truck will start to vibrate/shake above 68mph and continue to do so as speed increases. The vibration is not really coming from the steering wheel, but through the gear shifter and the floor boards. It is a very rapid oscillation and quite annoying. For reference, the truck has 205k miles on it. I have had the truck since 103k and have not had to replace any of the items listed below while I have owned it. This does not mean that the previous owner didn't as I know he replaced the IP.

Items I have ruled out:
Tire Balance - I have had the tires balanced and rotated TWICE last week. No change.
Rear Drive Shaft - I replaced all three u-joints and the carrier bearing this week. There was some slop in the carrier bearing. Vibration slightly less, but still present.
Front Drive Shaft - I removed it tonight. No change.
Engine Vibration - With the truck in neutral, I slowly ran it up to about 2700 rpm without any vibrations.
Steering Linkage - all tie-rods are tight with no play
Steering Gear - No excessive movement
Track Bar - Both ends are tight with no movement


Possible Culprits????
Ball Joints - Ball joints on the driver side do not have any movement. Ball joints on the passenger side have very little movement. Only reason I question this being the immediate cause is I would think that with bad ball joints, I would feel the vibration in the steering wheel and not in the shifter/floor boards
Shocks - the normal signs that I know of for bad shocks is excessive tire wear and/or bouncing. With having rotated the tires on a very regular basis, tire wear is not a good sign. Also, the truck doesn't bounce excessively going down the road, but with the suspension as stiff as it is, I cannot really push down on the truck and find out if they are bad. When I jump up and down on the bed of the truck, it barely moves at all. I hesitate to just replace the shocks thinking they may be bad because I want to go with some Bilstein 5100's when I do it and those aren’t cheap.
Hub Bearings - I do not hear any sounds coming from the wheels, but I do not have any other experience with these type of wheel bearings.
Warped Rotors - I have read that warped rotors/drums can case vibrations like this and I do get a pulsing some times when applying the brakes, but it is definitely at a different frequency then the issue I am having now.

Any insight on this before I just start throwing parts at it? Remaining items are relatively expensive and/or time consuming to replace.

SIXSLUG

If it isn't doing it when sitting still its got to be in the driveline.

Check to see if your driveshaft has thrown any balancing weights off. I would also check the pinion bearing.

Call the tire shop and see if the same guy balanced your tires both times and if he knows what he is doing. Not unusual to have a new guy putting all the weight on one side of the tire, spreading it out helps too if it requires a lot of weights.

If it doesn't vibrate in N at 2700 revs I would start looking at the driveshaft out to the tires.

StevenAg03

guess i should have mentioned that the u-joints and carrier bearing were installed at a drive shaft shop and they checked the balance so that is good. Not sure on the pinion bearing. will take a gander and see if i can find any play.

It was Discount Tire. The first time it was done i watched the guy do it. on the first tire, he put the tire on the machine, spun it, looked at the weights, removed the ones that were on there, and then added the new ones. Subsequent tires he removed the weights before he spun them. Hindsight says that first tire was probably out of balance. The next night, i went in and told the counter guy that something was wrong. I watched him balance them as well. He recalibrated the machine and removed all the existing weights before balancing them.

thats what lead me to the ball joints and wheel bearings.

SIXSLUG

Bad balljoints usually cause wandering. I guess an out of balance tire and worn shock could cause vibration.

When I had a bad u-joint I could tip my mirrors down and watch the rear tires for bouncing, there wasn't really any so I figured u-joints and found a bad one.

I guess you could hang out the window to see if the fronts are bouncing, but would probably feel it in the steering wheel.

One of your u-jonts may be munged up.....

rickf

Check to make sure the front tires are not cupped. That can cause a vibration that can sound like a differential bearing. When I balance my tires I will spin them first with the original weights to see if they are actually out of balance. Then I will remove the weights and spin again and put on the recommended weights. Keep in mind that I am doing this myself so there is no labor charge involved. If you go in to have the tires balanced the first thing they should do is remove the old weights before spinning it.

StevenAg03

i re-checked the feel of the rear u-joints last nigt and they felt good. front drive shaft hasnt been in since yesterday afternoon. Maybe tonight i will remove the rear drive shaft and run it up to 70 and see if i have any vibrations... In all seriousness, the comment about the tires and work shocks is why i put shocks in the original message...

I know what badly cupped tires sound like, but there is no sound involved with this vibration (other than the broken dash... ). The front tires have been on the front for all of 5-600 miles so there are no signs of cupping yet.


thanks for all the input guys...

SIXSLUG

My rear u-joint felt tight but was creaking pretty good and had some rusty dust around two of the four cups...a sure sign of a bad joint.

KATOOM

First off.....You cant rule out most of what you listed because all those parts can be contributing to the issue but not actually the problem. The simplest way to determine where the vibration is coming from is to ask.....is it a "fast" "harmonic" vibration or a "slower" more "wobbly" kind of vibration. Driveline stuff will be the fast harmonic type of vibration since those parts are spinning fast, where axles, bearings, and tires will be a slower wobbly vibration since those parts are spinning slower and tires are larger.

As mentioned, tires are usually the culprit, especially by what you just described. You can have them balanced or rotated until the tire shop wont let you around anymore but if they are not perfect then they'll always run out of round since worn tread or slightly misshapen casing or tire age or poor quality construction or inept ability to balance the tire can all be a problem. My last set of tires looked perfect but would never ride good on the highway. I had them balanced over and over until I got tired of the tire shop guys scratching my stuff so I left it alone until one day I noticed that the tread was separating from the casing on one tire and starting to on that others. Got a new set and all my high speed ride issue went away.

SIXSLUG

I like Katooms direction on this. Dad's 94 had a 60mph+ vibration that just wouldn't go away. Driveshafts, brake drums tires shocks, twice over by the dealer and still vibrations.

Hayseed mechanic asked him if the wheels were round. He checked, they weren't, one over 1/4" out of diameter! dodge dealer took to the two worst ones and "lost" them. But did end up replacing alll four wheels in 98 IIRC.

Let us hear what you finally find wrong!

StevenAg03

UPDATE:
So I ordered a bunch of parts and installed them the two weekends ago. Results are below:
XRF Ball Joints - No Change
09-10 Steering - No Change (didnt expect it to be the issue cause i wasnt getting death wobble)
Steering Box Brace - No Change (didnt expect it to be the issue cause i wasnt getting death wobble)
Bilstein 5100 - No change
3rd Gen Track Bar - No change (but then again, its still sitting in the living room so no change is to be expected... )

so after all this, i was at a loss. I took the truck one last time to Discount Tire and explained the situation to them. The tech there was real knowledgable and worked for 2 hours to get the tires balanced and minimized runout. He let me watch the entire process and explained everything they were doing. Result was that two of the four tires were out of round. He did the best he could with those two tires and told me to drive it a little bit and see if they got any better. Well, the didnt. Yesterday, i had all of them replaced under warranty for free (had to pay for new certs) and truck no longer vibrates. One thing i realized after driving with the new tires, the truck was vibrating at all speeds. what i thought was just the stiff, heavy duty suspension was the tires.

moral of the story: watch the guys doing the alignment and watch the tires. They balanced no problem, but you could see them vibrating.

SIXSLUG

The dealership threw every part but a new engine at dad's truck, even was proposed a new trans but didn't get one. After the warranty ran dry he kept after them, when the other guy found the problem the dealership asked for the wheels to inspect them. Dad gave them one and kept the other, they misplaced it and asked for the other one, then agreed to pay for 2 of his new aftermarket wheels that he had put on....

Vibration gone.

j-fox

What brand of tires?

KATOOM

I am a stickler about my tires. I'm not going to pay hundreds and hundreds of dollars for tires and have them ride like garbage. Thats simply not acceptable. Some people dont care but I do. I've never worked at a tire shop but it almost seems like they intentionally do what they can to shut you up while you're there and send you on your way all knowing that most people (me included) dont have the time to come back and sit for an hour or more just to have them fix what should have been done right the first time. So you drive for (X) number of miles which only makes the problem worse before you come back and repeat the whole process. Well by the time you're angry enough to do anything about it, the tires are just about old enough to replace. Ya.....I think its a scam.

StevenAg03

BFG AT KO. In all honesty, these new ones make the 4th set on the truck since i have had it (100k miles) and i have never had a problem out of them. i think the issue was that the truck sat for 10-11 months while i was in the sand box. thus, creating flat spots...

most all tire stores i have been to, discount tire included, have young(er) kids working the bays. And, i agree with you on most all places out there. the guy that worked on them for 2 hours and told me to drive them for a bit ws not the stereotypical tire changer. he was extreamly knowledgable. The reason he told me to drive it for a bit to see if they got better is because they have to jump through hoops to get a tire manufacturer to take them back. this is compounded by the fact that mine were half gone.

the stereotypical guys in this situation were the two that did the balance the first time(s)... different store, different city...

hhrumph

I agree with sixslug, Tires are most likely "out of round".