We're on the road and I'm getting a vibration at speeds under 40. Doesn't seem to be brake related - does it when not braking and no pulse in the pedal. Does not do it all the time either. Can't narrow it down to turning or allerator position. It comes and goes. I've had the following thoughts and suggestions already: wheel bearing, u joint, wheel balance. It feels like I'm passing over old rumble strips, the kind they use to get your attention approaching a construction zone. Not stong, but like really really worn down ones.

My connection to the net is iffy -- have to stand in the middle of a field and even then it is weak. I'll check back in the am.

Thanks for any suggestions in advance.

Camper

2002 350 crew long bed 4x4
97K miles

 

Check your tires you might have a blown belt and have a bubble

 

First step for me would be a proper balance/rotate. If you have a wheel that threw a weight it might vibrate like that.

Holy &*%^ Justin. Hahaha..

 

just a thought,,

That sounds kinda like the sound mine is making, which is the driver side 4x4 hub has come loose inside, and would start to make a rumblestrip type of sound.

Next time it does it, put her in 4x4 and see if it goes away.

I've just been driving mine in 4x4 till i can be without it for a few days.....

 

Check your ball joints! Mine started doing the same thing and every once in a while it sounded like somthing was hitting the floor under the truck. I went looking for a bad wheel bearing and found two bad ball joints and a bad spindle bearing. Replaced all ball joints, bearings, seals and o-rings for less than $300 with shipping. All vibration and hitting floor is gone and the truck drives like new.

 

Thanks all. I did get to try it in 4x4 last night, no change. The front hubs are unlocked, confirmed by getting under the truck and turning the drive shafts on either side. I was wondering about a wheel weight too.

When I figure it out will post it. Have to run 300 miles this weekend with 10K trailer. Fingers crossed.

 

Got'r home ok. Vibration is worse. Spoke at length to a cousin who is a diesel mechanic. Thinking u-joint. Have to go to another funeral tonight, maybe mechanic tomorrow.

 

OK, Finally got it to the mechanic. Tough call, could be a lot of things he says. So here's where I am:

does not vibrate during braking
not during turns that I can tell
4x4 engaged or not no difference. Same for locking front hubs.
still vibrates with trans in N and engine shut off, coast to stop.
only sound is occasionally sounds like I have aggressive treaded tires on

Possible Causes:
front bearings
u joint
transfer case
tranny (doubted)
LS rear end

Next steps:
change transfer case lube
drop rear drive shaft, check u joints

Any other input? Oh, installed a DP-tuner less than 2K miles back. (WOW!) It has no start, stock, high idle, 60e, 80e, 60 tow and decel. I've been running in stock the last few days. Tow a 10K # camper a lot.

Camper

 

you took it to a mechanic, and he didn't know??? what kind of mechanic was it, one that didn't want to tell you the truth for some reason?

you don't think it's ball joints?

are you thinking about taking it to a front-end shop?

 

I would pull thr rear driveshaft and then drive it. Check the u joint. a seized joint will cause a vibration like that.

 

I to am leaning towards the U Joints..When you put her in gear, listen for "clunk", or when you are doing 25 or so, take your foot off the pedal, then hit it and listen for a "clunk"..

 

Does applying the brakes make the vibration go away?
If so, I'm pretty sure it is failed front wheel bearings.
Applying the brakes sort of re-aligns the wheels temporarily.

 

Applying the brakes makes no difference.

He's leaning to a u joint, as am I and a cousin. And I do trust the guy. He's done work for me for years. I'd rather an honest answer like that than a parts changing, money burning experience. Everyone agrees that it is in the drivetrain, so not taking it to a front end shop.

Of course what ever it is keeps getting worse. Pulling into the parking garage this am I could feel it only when I turned sharp. A pulsing pulling, almost like the hubs were locked (which they were not). Got to drive it more later and jack it up.

Camper

 

Sounds too simple to even mention. Have you checked your lug nut torque specs? With the miles you put on since you noticed the problem it is highly unlikely but,,,

 

Sounds like a U-joint to me. I had a similar problem to what you are describing and it was a bad u-joint.