New transmission, transfer case and hubs. This vibration occurs at about 35 when in 2wd when i switch the knob to 4high the vibration goes away?????? As previously stated the hubs, trans, and transfer case are new. I'm thinking the vibration is caused by something in the front end of the 4x4 that when free spinning causes the vibration but when locked the vibration is gone. ideas?

jared

Hmmm...it goes away in 4x4 eh.....

Does the vibration stay all the time from 35 and up or is it just around 35? Could be a tie-rod cuz it doesn't sound like an un-balanced tire.

I think the best thing would be to have a service station find that one out, unless the truck is fairly new. Get the dealership to do it if so cuz it may be a warranty item.

Check all driveshaft splines, front and rear. When loading changes between 2WD or 4WD, these can cause vibrations.

Another would be if you rasied the vehicle, pinon angles changes can cause vibs as well.

I have a 95 F350 7.3 diesel and I experience a vibration in my truck between 35 to 45 mph. I don't have a clue what it is either. I have had a bunch of stuff replaced on my truck within the year.

I've had several 4wd's that had a similar symptom. It would only occur when the front hubs were locked in but the transfer case was in 2wd. The front drive train is spinning freely and often the U-Joints and splines are somewhat sloppy - this will cause a vibration. When you lock in the transfer case (put it in 4wd), the front wheels are geared to turn slightly faster than the back wheels, pulling the truck straight. This causes torque on the front drive train which oftentimes eliminates the vibration at that speed.

I have a 99 F250 4X4 SD 85K with the same problem. However I get a loud rumbling noise with the vibration. Sounds and feels like running over those "Wake-up grooves" on the side of the interstate highway. Happens intermittently between 35 to 65 mph. I slow below 35 it'll stop or I activate the 4x4 switch on dash and it'll stop. Ford said I had a worn out hub. I replaced it but the problem still comes and goes. I think my unk. problem may have ruined my hub. It's been in the shop several times but nobody can find anything wrong.

I own a 96 F350 4x4 that when my right front wheel hits a bump at about 30 mph a strong vibration starts. The only way it stops is if I mash hard on the brakes and slow the truck way down then it goes away. I recently replaced all my bearings in the front hubs and tie rod ends. I thought that solved my problem but a couple weeks later a hit a small bump and the vibration was back. I would think if the problem was with a brake rotor it would be all the time. I once had a Toyota truck that the front end started to shake at 55 mph and if you speed up to about 60 it would stop. The problem on the Toy was the tires wore out of balance but that shake was all the time?

Do you have standard size tires on the truck or did you put larger tires on?

I put 285/75's on my 96 F250 and noticed a little of what you're talking about. I purchased a shock absorber assembly that mounts to the tierod and that took care of the problem. Since you've replaced tierod ends, I'm assuming you had the front end aligned - that would be my other suggestion along with balanced tires.

Jared, pull off your front driveshaft and drive it. I bet the noise goes away. Have someone drive next to you and see if your driveshaft is turning while you're driving in 2wd. If it is, crawl under your truck and see if the driveshaft spins freely in 2wd. If it doesn't, you're hubs aren't releasing. If it does, tie the shaft through the u-joint to the frame to keep it from turning and test drive it. If the vibes are gone, your driveshaft is out of balance, yoke angles are off, u-joints are bad, or splines are worn. All can cause vibration. Also make sure your driveshaft is timed right. Both u-joints must be on the same plane, that is the yokes have to have the u-joint caps pointing in the exact same direction. If there isn't a spline key on the slider yoke to align them, you could be off time.
Jamaro, check your alignment. Sounds like you have too much toe out or not enough caster angle.

I own a 96 F350 4x4 that when my right front wheel hits a bump at about 30 mph a strong vibration starts. The only way it stops is if I mash hard on the brakes and slow the truck way down then it goes away. I recently replaced all my bearings in the front hubs and tie rod ends. I thought that solved my problem but a couple weeks later a hit a small bump and the vibration was back. I would think if the problem was with a brake rotor it would be all the time. I once had a Toyota truck that the front end started to shake at 55 mph and if you speed up to about 60 it would stop. The problem on the Toy was the tires wore out of balance but that shake was all the time?

That is exactly what mine does. Anyone ever get a resolution on what causes this damn rumbling noise.

I have a 2000 f350 6.8 and on 2 occasions had a terrible vibration from the front end. The first time the repair shop put new tie rods did not help I read in a forum to make sure air pressure was correct, it was 10 pounds low added the air and fixed the problem. Recently a had a similar problem at 40 mph the truck developed a shimy that would not stop unless I slowed down to 25 or speeded up to 60 (with it shaking along the way) the problem turned out to be a unbalanced tire.

I would also check for a broken shock in addition to other mentioned problems.