2007 F150 Screw 6.5" Box 4x4 3.73 LS rear end.

I have a shimmy at high speed only that I cannot solve. I have read all the threads that have 'highway, highspeed, shimmy, and wobble' in the thread (that I could search that seemed to make sense).

I find it strange it started a day after I rotated my tires and the first time I drove over 60mph I started to get a shimmy. I also towed a little utility trailer that day (I can lift the thing by hand so I know it isnt too heavily weighted).When I had my tires rotated is when it all started so I naturally thought I had to get my tires re-balanced. It didnt fix it so I then had them balanced again. Then they road-force balanced the wheels. Then they tried to match the wheel to the tire and it said it was pretty close. Then they checked the run out and it was fine. The rear right tire needed 5.25oz on the inside of the rim. We ran out of time and I was going to ask them to rotate them back.

I was worried about the fact that I did the 'soft brake pedal mod' and in one of the threads said that is was a potential problem. I have 25,000 miles on the rod so I doubted it but I backed it out anyways. No change.

At the next opportunity I took it to my buddy who works at a Ford dealer. We threw it up on the hoist and it the first test was the UBJ, LBJ, and Tie Rod ends. The UBJ on both sides were bad. The Right LBJ was gone. The Right Outer tie rod end was gone. I had them replaced. The shake was still there.

I was told they noticed the front brakes were gone. I had 3mm on the front and the rotors were gone. I swapped them out today. No change, shake is still there.

Obviously I need to swap the front and rear tires back to check it out. I dont know how that would matter where they are located, if they are out of balance they are out of balance.

Any ideas......

 

It's not in the balance, that would be more likely to make it bounce or hop. If the runout was good I would suspect that maybe you have a belt shifting in the tire.

The reason it doesn't show up on the rear is because the rear axle is fixed and only travels straight. The front on the other hand articulates (turns and leans) and is connected to the steering wheel.

That's my guess.

 

So if I rotate front to back and it goes away, that means one of the tires is going.... does that mean the tire is about to go if the belt is shifting or can you drive on it like that? I still have 10/32nds on the tires!

Thanks for the help.

 

I hade a bad shake at 60mph and was going to do every thing you did but ended up getting new rims and tires and a alignment. Shake was gone. Can you barrow two wheels and try to narrow it down. That might work

 

If it's shifting you can only guess when it is going to go. You could have a good tire shop look at them, not some place with a bunch of pimple faced kids.

Take a real close look at them. You are looking for slight bubbles in the tread where it might be lifting. Also look real good at where the tread meets the side wall for strange looking wear.

If it is the tire, do you have road hazard on them?

 

The tires could be wearing funny.

 

Thanks guys, I am going to go and take a look at them. They were roadforce balanced but who knows right. I am going to try and swap them around and see what happens.

If anyone has any stock 18" tires that are almost dead. Please let me know. I want to throw on something old and see if it goes away BEFORE I spend another grand or two on the truck this week. I am located in Calgary Alberta but travel over most of Alberta. This is better than recycling because you get a case of beer!

 

X2 on this.

My tires aren't wearing evenly and my 06 has a shimmy at highway speeds.

Definitely something to check

 

^^ thanks for the idea. What isnt wearing right? Like inner compared to outer or what exactly.

thanks

 

i had tires go bad after i put alot of weight in bed ,had a shimmey really bad

 

Correct,

Please see pic below, obviously this is a more severe case than what you may have going on, but it is definitely something to take a look at.

 

thanks guys, I will take a look. I am swapping my bald stock tires back on today to see what happens. I will inspect the one corner I suspect a lot once it comes off.

 

Well so I got new to me tires put on. Shimmy seems to be gone 99% of it. I think either the rims have a hard time balancing (two tires took 1.00 and 1.5 and the other two took 4.25 and 5.50) because of the funny lip or they are bent.

It is more than good enough to last until I get the winters on. The winters are stock size and the rims are stock so they should balance fine.

I will let you guys know if I find out more but we will see.