I've been fighting a vibration in my 2000 F150 4x4 ORP (extended cab, w/ 8' bed) since 9k miles and now have almost 25k miles. I've had the truck to the dealer 3 times in the past year, and they can't seem to find the problem. It does it between 40 and 45 MPH whether I'm speeding up, slowing done, coasting, or coasting in neutral.

Ford has supposedly checked the front suspension, the transfer case, the transmission, and checked for TSBs. They can only detect a slight vibration, which they said that that typically indicates a tire problem. I also had the rotors turned.

I took it to a Goodyear distributor and had all 4 tires balanced about a month ago. This seemed to help but it didn't solve the problem. I returned today and had them check to see if a tire(s) were out of round, or possibly a belt had broken inside a tire(s). I've got Goodyear AT/S LT265/70/17. They rebalanced the tires and checked them and said they were very smooth, and that wasn't the problem. They also said I don't have a warped wheel. The tire guy also felt it and described it as a bouncing or hopping feeling and said to have Ford check the transmission or suspension.

Has anyone else experienced this problem? Any tips on what to have Ford check next? Any ideas on what is causing this harmonic oscillation?

 

Did they try roatating the tires to see if it changed the vibration at all? Every once and awhile someone will get a tire that looks good, balances out, etc, but still causes a vibration. The only way to find it is with a newer computerized balancer that checks for road force variation. It has to do with a difference in the dinsity of rubber throughout the tire. Hunter makes a nice road force variation balancer, but you only see it in performance shops because it runs about $15,000.

-Jon

 

I rotate the tires w/ every oil change, and it is always present. It's due again in about a week, so I'll rotate again and see if there is a difference. If I recall correctly, it is worse with the tires I've got on the front now.

 

They rotated the tires when they balanced them, and I can't tell a difference in the shaking.
Is it possible it's the driveline vibration TSB? I wouldn't call 40-45 'high speed', and it doesn't occur afterany 'extended' time. If it's the driveline would it still shake when it's coasting in nuetral since their is now power being supplied? I also checked the bushing area ans there are no signs of any fluid leak.

 

Have your drive shaft checked out, I know that if it's bent in the slightest you will have a serious vibration problems at certain speed.

 

I took it to the dealer today and they put it on a reed tachometer. It indicated a secondary tire vibration. They were going to put the wheels on their balancer to check the wheels and tires, but their balanced seized up.
I mentioned the new balancer that Ford4ever mentioned, but they don't have one. They went on to say Ford has put out a TSB for vibrations and to use on of these balancers to check the tires. However, they were unaware of anyone in the area that has one.
I'm suppose to go back next week after they have their machine fixed and try again

 

I've got the same problem, except mine is between 62 and 65 mph. Very very slight rear-end vibration. Seems to be coming from the driver's side. I've rotated teh tires, checked inflation, had them rebalanced. Not much of an improvement.

Since it is not really bad...I'm just letting it go. It might just be a bad tire or slightly warped rotor. Started at 3,000 mles and truck now has 11,800 miles.

 

My 98 4x4 Supercab had a vibration at 60 to 70 mph...Took a long time to find (noted at 26k..fixed at 64k 1 1/2 years later), but turned out to be pinion bearing in the rear axle. Ford fixed under warranty. Axle was a 3.55 open..not sure if applicable to your case, but hope this helps..good luck...

 

I had the truck back to the dealer today. Turns out both the rear tires have excessive runout, and the one on the left side has a 'hop' to it.
The Ford rep told me it's a now a warranty issue on Goodyear. I went to the local Goodyear distributor, and he said the warranty for excessive runout ends after the first 25% of tread life and I'm around 40% now - and the warranty doesn't cover prorating for this. He said I should talk to Ford becasue they let it go this long. Went back to Ford, they were clueless as to what the Goodyear guy was talking about and referred me to another Goodyear dealer.
I called this Goodyear dealer and he said Goodyear would prorate my tires. i'm just glad the problem was solved.
Thanks to everyone that posted!