I just bought a 97 Ford Louisville dump truck, it has a bad vibration that starts about 25mph and stops about 35-38mph. It runs smooth after this. It doesnt appear to shake the steering wheel I have owned dump trucks for 15 years and this has me looking for help. I dont have a history of the truck and bought it with a leaking head gasket which is fixed Tire shop says its front tire, replaced no change I have shook all the ujoints, no play This is a quad dump and it has two drivetrain, midshaft bearings and they appear to be OK. Yokes are in time What I plan on doing next, is to jack up the rear axles and run the truck in gear, to see if I can detect the problem area I would think, if its a rear tire,bent rim, bad ujoint, it would bounce all the time any suggestions:Banghead
I have owned 2 on which a bad rear tire caused a severe vibration at a certain speed, which stopped at a higher speed. One was a real nice CH Mack that Nealy-Coble Freightliner had spent a lot of money failing to find the vibration on. What I do is swap the rear tires 2 at a time until it stops
good idea, hopefully get around to it this weekend
I just had a similar vibration, it would start at 45mph. I was sure it was driveline related but could not find anything loose and all u-joints were good. I finally found a yoke that was getting loose on the front differential directly behind the u-joint. Put a new yoke and nut on and tightened it to specs and the problem went away.
sounds like a tire on the drive to me
I changed one of the almost new front tires (385x22.5) on Thrusday, no change. I know there is still one more left to change, but its a Firestone (95% tread) I did have the tire shop check the tire and they said they couldnt find anything wrong with it. I talked to a mechanic today and he worked on a 1998 Ford, same model as mine. It like to run him crazy, he finally found out it was the front brake drums. He installed balanced drums on the front and it solved the problem. I will check to see what style drums I have I will keep you posted
Well the steering axle has brand new balanced 385x22.5 tires on it now, still has the vibration I guess I will start changing the drive tires, two at a time more to follow
can you put the truck in the air (with rears off ground) then start it that is how i find problems in my shop.
Drivers says today the vibration is still there, plus a new vibration Took the truck back to the tire shop and had two new Firestone 385 tires, these tires are upgraded from the cheaper tires from yesterday Still the same vibration.. Took it to a truck shop and I guess they dont know what to check, so I jacked the rear tires up (as mrkw77 suggested) and ran the truck, noticed the back driveshaft was shaking, like a bent shaft. Took the driveshaft out and plan to take it to the shop tomorrow more to follow
Please let us know what it is as we all have these problems , I pulled all the rears and drums off one and ran it in the shop on blocks, it was the tail bearings in the tranny
i bet the splines in the jack shft is shot if you can lay under the truck and push up on the drive line and it moves up and down in the middle its shot. I have swapped out the female part and solved the problem. hope that helps
OK problem is fixed, but not after alot of hair pulling. This truck had new recaps on it when I bought it (just a note) The problem turned out to be three tires and rims, Im hoping only one rim is bad, all are aluminum rims, but someone had welded 4 places on one of the inside rims HUMMMM not good I know I should have checked the tires first, but who would guess 3 tires out of round badly I did before the tire thing, have the back driveshaft checked for straightness, no problem tighened two yokes, coated splines with locktight replaced two Ujoints I guess the out of round tires, were causing this looping sensation at 30-40mph I think all I have done, was needed, but boy was this a bad process, to have to go through
I feel for you Willis, went through basically the same aggravation with my new IH road tractor. A major P ITA it was until we found that bad yoke along with it being loose. I also put on 8- new rear drive tires (recaps) along with several other things.
Willis, To make you feel a little better, I'll tell you about a real nice '94 Mack CH613 tractor I bought from the largest Freightliner dealer east of the Mississippi about 10 yrs ago. I went out and drove the truck and agreed to buy it if they fixed a bad vibration from about 30-40 mph. The truck had 10 virgin 11R 24.5 tires on it at 90% and better tread. They called me back in about 10 days and gave me a list of what had been done w/ no effect, and offered me the truck at a deep discount. What I remember is that they had: swapped both steer tires and rims with brand new ones off another truck after having them balanced replaced the u-joints replaced the driveshaft center bearing replaced the transmission rear bearing sent driveshaft to be balanced and checked for straightness replaced trunnion bushings (I had put this on my list of needed work) changed trans mounts/ rear engine mounts (Mack, after all) I suggested they swap rear tires, but the service manager said rear tires wouldn't cause this, and the sales manager said they weren't spending another bleep bleeping dime on it. I brought it home and the 4th pair of tires I swapped fixed it. One of the tires wasn't too bad, but the other bounced so bad you could feel it on a dump trailer, so I gave it to a logger. The other truck I had this on was a 1971 Chevy C90 tandem dump w/ 10.00-20s on walking beams. It was easy though, you could look in the mirror and watch these jump. Glad you found it, Mitch
amazing what we (owners) go through with trucks