Truck Specs:
2003 F250 SD CC 7.3L 2WD
6" Pro Comp Lift

When feathering the throttle around 65 mph I get a slight grind/vibration. This "slight" noise gets much louder when I speed up to around 75, but typically only comes when coasting or slightly pressing the pedel. The noise disappears when I peg the throttle or brake.

I can also hear/feel the noise/vibration at lower speeds 35 - 60 mph when I slightly feather the gas pedel.

U joints on driveshaft have recently been replaced (which resolved other noise issues I was having).

I am trying to find the source of the problem before it gets much worse and possibly more costly to fix.

The noise/vibration appears to be in the front of the vehicle, and NOT travelling up the drive shaft from the rear diff.

Could it be a front wheel bearing?

Thanks in advance for any ideas!

 

Do you feel this in the steering wheel, in the seat of your pants or just "all over"?

If it is in the front, my first impulse would be to check your front brakes.

 

It seems to be more on the floor and the seat than in the steering . . .

The brakes are relatively fresh, I changed them out on all four corners about 15,000 miles ago. I'm not ruling that out but it seems a little too "different" of a grind to be the brakes.

 

If you feel it in the floor and the seat I don't think it is in your front end. I'd check your carrier bearing.

 

The carrier bearing, driveshaft, and rear end have all been rebuilt within the last 15,000 miles as well.

I replaced the U joints within the past 2,000 miles.

I'm really at a loss . . .

 

I'd go back over all of those. Questionable parts can wear out within 1500 miles. 15,000 miles is well beyond "new". If they aren't bad that noise might be very expensive.

 

How much drop is in your carrier bearing? Sounds like you have WAY too much drop..

Not enough drop = Low Speed vibration & noise
Too much drop = High Speed vibration & noise

 

Im not sure the drop on the carrier. I will measure it and see.

What is the typical carrier drop per inch of lift?

I have seen people state anywhere from 1/4" per inch of lift all the way to 1/2" per inch of lift.

 

It varies.. You just have to do it by trial and error.. I run 1-1/8" of drop for my 4.5" and I have no vibration or noise.. Buddy who has 5" lift runs 1-1/2" of drop.

 

Are there any manufacturers that sell a shim kit?

 

Call Marty at Truck Toyz Performance.. he can get you a shim kit.. 1-888-PRO-TOYZ

They are an FTE Sponsor

 

Awesome,

Thanks a bunch Storm.