Some of you may have read this old thread I started a long way back in September of 2011…

https://www.ford-trucks.com/forums/1...l#post10842388

I thought I would start a new one though since that one went off on a tangent discussing the ball joint replacement, which didn’t help anything. Since then I have replaced the front ball joints, steering damper, hub bearings, tires, and most importantly have replaced the brake rotors and pads on all four wheels. I finished up replacing the rears last night and took it for a test drive this morning. The vibration seems to be slightly better, but it is still has a bad vibration when braking. I serviced the slide pins as well when I did the brake job and none of them were sticking and the boots looked good (and look even better after treating them with PB Blaster). I’m fairly sure it is the back since there is no vibration in the steering wheel at all. I was hoping it was the rear rotors since they had a lot of pitting and grooving on the back, when I saw that I thought I had found the problem.

My main question is what to try next. It has taken me this long to get this much fixed because I don’t drive the truck very often and money has been tight the last two years due to medical bills for my daughter. Luckily everything I have changed out so far needed replaced anyway, but it is still frustrating to dump this much money into the truck and still have this vibration.

Thanks in advance for any advice, I have to say this community is the most helpful group that I have met online. I belong to a lot of other forums such as for computers, other vehicles, etc... and none of them are as helpful as the folks on FTE.

 

Since my truck is not four wheel ABS I decided to rule out the ABS system or VSS sensor. I crawled under the truck and unplugged the VSS. I drove down the road and back and it is acting exactly the same, other than the ABS light and the very hard shifts obviously. Part of me was hoping the VSS was acting up since that would be cheap, but if it had been some part of the ABS I'm sure that could very expensive. Does anyone think it could be possible for it to be the brake hoses going bad?

 

I do not see how a bad hose would cause vibration while braking.

The usual culprit is a rotor, but you replaced them. Tell us, do you feel this vibration in your seat, the steering wheel or the brake pedal?

 

I think one rotor is still not true also check all the bolts related to the brakes/wheels.

 

maybe check for runout with the rotor on the truck? if you're lucky and there is some, you could rotate the rotor 90 degrees to see if it changes

 

The vibration cannot be felt in the brake pedal or the steering wheel. It is kind of a shimmy that seems to originate from behind you. Also, when this first started I was using it as a daily driver for several weeks while I was doing some drive line work on my Nissan. For several days before it was fine and then it started suddenly on my first stop on the way to work in the morning, and it has been doing the same thing every since.

 

Check all your rotors again.

 

Any possibility that you have a driveshaft that is twisted / out of balance? Maybe a seized U Joint?

 

Twisted driveshaft?

 

I took it, once again, for another test drive to see if I could pick up on anymore details on the vibration. (And to take my daughter on a quick off road adventure before I put her to bed as we live on the edge of wide-open BLM land). I even tried putting it in 4WD, not sure what it would have proved, but it's still the same in 4WD. I also stopped the truck from about 35 mph with the parking brake, and it has the same vibration! I'm starting now to lean towards the u-joints. I'm tempted to pull the drive shaft out and take it for a quick drive in "front wheel drive" and see if it still does it, if not I'll have my culprit. At least the drive line u-joints are cheaper than the steering knuckle u-joints. And just in case anyone is wondering, all these test drives are being done on fresh smooth asphalt down the road from my house. We have so much washboard near my house that it is hard to tell if anything is wrong with your vehicles without getting on pavement.

 

I'm going to try rotating my tires front to back before I do anything drastic, but since I'll have the tires off and I have a run-out gauge available I'll go ahead and double check them.

 

If you stopped from 35 MPH using your parking brake, that rules out the rotors. The parking brake uses a drum inside of the rear discs.

 

I have seen bad wheels that cause a shimmy.

 

It sounds like it's coming from the back then. Sounds like something is loose back there. Check all the bolts, shake the rear wheels, spin them, and concentrate on the back. U-joints won't cause it.

 

Exactly, that's why I gave it a try. I was kind of surprised with the outcome to be honest.

I figured rotating front to back might move the vibration if it is a bad wheel. If it is on the back and I move it to the front I figure I should be able to feel it in the steering wheel and it will feel different.

Everything in the back seems fine, but it looks like I might have to jack it up again and inspect everything and maybe even check the torque on the u-bolts and other items. I already inspected for broken springs and items like that but didn't see anything. I hauled enough lumber yesterday for the overloads to touch. And the truck drove fine, the vibration was still there but I think the weight dampened the vibration a little bit.