Strange Vibration

Shawn T · March 15, 2011

Yesterday while returning home from an 1800 mile road trip, I began to feel/hear a small vibration which I thought was coming through the wheel. It got increasingly more frequent but is not constant. It happens on acceleration, coasting, braking and seems to be more frequent at speeds between 60 and 70. As it became more intense it seemed to be coming from the drivetrain somewhere. My wife could not feel or hear it until it became more intense. It was extremely hard to destinguish it from road, exhaust and engine noise but it feels and sounds like a flat tire, or a grindy-wabbly sound. Whatever the hell that means? I don't even know where to start. I have to top off my transfer case every now and then because the yoke leaks, could it be that? At first I thought front wheel bearings but it doesn't seem to be coming from the wheels. It is almost a shudder. Please, any suggestions......

KMGZ400 · March 16, 2011

make sure your tires are balanced.... had the same exact problem and my tires were not balanced correctly... could be balljoints.. just my 0.02

SouthCo · March 16, 2011

I may way off but could a wheel weight have fallen off during the long trip?

Ahh, after re-reading your post sounds like it's more than a wheel weight.

Debo511 · March 16, 2011

Sounds like a possible brake drag. Does it get worse the longer you drive?

Shawn T · March 16, 2011

Sounds like a possible brake drag. Does it get worse the longer you drive?

It does get worse the longer I drive. But it started at some point I guess. Could that just mean my brakes are worn to a point that they are hanging up on me?

ChevyTech77 · March 16, 2011

Stuck calipers, caliper pins or brake pad guides are the only thing that could cause a brake drag from wear and even then, it would be very minimal drag at best. Not enough to cause a vibration. The next time it does it, pull up on the brake pedal with your foot and see if it gets better or goes away.

CoastyAV8R · March 16, 2011

Stuck calipers, caliper pins or brake pad guides are the only thing that could cause a brake drag from wear and even then, it would be very minimal drag at best. Not enough to cause a vibration. The next time it does it, pull up on the brake pedal with your foot and see if it gets better or goes away.

Also feel your brakes to see if they are warm/hot, if they are then your dragging a brake. If it gets worse the longer you drive, chances are it's not your tire balance as that would do it right from the start as well.

Shawn T · March 18, 2011

Haven't got a chance to do a highway test yet, but have ran a few errands around town and nothing. Have been searching far and wide on the forum and there seems to be a trend with dry driveshaft spilnes and u-joints causing a random shudder/vibration. A couple of things.........

1. Have had a pipe on for about 4 years now, so I can eliminate exhaust drone, as it has never happened since the install

2. I mentioned the yoke leak and called the "mechanic" who worked on it and asked him if he had done any other work besides change the prop shaft seal. He added this

a. When he determined that the seal was not the leak, he searched for TSB's and found that this year of truck had problems with yoke castings having porosity. So he removed the driveline and proceeded to fill the prop shaft with rtv and reinstalled it. His hopes were to essentially plug the leak from the inside. Well, it still leaks so even an idiot can assume that there is a wad of silicone jammed between the splines of the prop shaft. Right?

3. I will do a highway test to see if I can elimate the brake drag theory this weekend.

4. The driveshaft u-joints seem to have no play, but that doesn't mean a thing right? They are pretty massive and may need quite some force to rattle. No tell tale "chatter" that usually occurs when a u-joint goes dry.

Any thoughts?

HawkScot · March 18, 2011

Haven't got a chance to do a highway test yet, but have ran a few errands around town and nothing. Have been searching far and wide on the forum and there seems to be a trend with dry driveshaft spilnes and u-joints causing a random shudder/vibration. A couple of things.........

1. Have had a pipe on for about 4 years now, so I can eliminate exhaust drone, as it has never happened since the install

2. I mentioned the yoke leak and called the "mechanic" who worked on it and asked him if he had done any other work besides change the prop shaft seal. He added this

a. When he determined that the seal was not the leak, he searched for TSB's and found that this year of truck had problems with yoke castings having porosity. So he removed the driveline and proceeded to fill the prop shaft with rtv and reinstalled it. His hopes were to essentially plug the leak from the inside. Well, it still leaks so even an idiot can assume that there is a wad of silicone jammed between the splines of the prop shaft. Right?

3. I will do a highway test to see if I can elimate the brake drag theory this weekend.

4. The driveshaft u-joints seem to have no play, but that doesn't mean a thing right? They are pretty massive and may need quite some force to rattle. No tell tale "chatter" that usually occurs when a u-joint goes dry.

Any thoughts?

Did it start after the rtv was used to stop the leak?

I would be cleaning the rtv out! It is useful where it is intended to be used but can cause all sorts of problems otherwise.

Shawn T · March 28, 2011

Problem solved this weekend. When I got the truck on the lift, I went to the front wheels and wiggled them. The right front had at least 1" of orbital play! Wheel bearing shot. Left side was good, so left it because I'm not fixing something that isn't broke for another $297. As you all probably know, you can't just buy bearings and races anymore, it's the whole hub assembly including the new wheel speed sensor. The good news is that from start to finish it was a 35 minute job. It took more time to run to the parts store. I still have the old unit, and there is a really good bearing shop here in town. Can the old hub assembly be pressed out, bearings and races replaced, and repressed? I would rather spend $80 buck for a reman, than buy another 3 bill hub. Drives great, no vibration.....