unbalanced tire - NOT-

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Mike T 3

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ok guys another round of asking help.



so about a month now everytime i take the ST up to 60=75mph ST would shake like i have a unbanlanced tire. well, i had already elliminated that since i had the tire balanced twice now and alligned 2 days ago. today it still shake A LOT, so i kinda pointed it to my right rear tire since the shake seems/feel like its coming from the back of the truck. (if its the front tire, then i sure as hell would feel a lot of it on the steering wheel right?)... so just to do a process of elimination, i had taken the spare tire and placed on the tire i think was doing the problems yet when i took it up to speed, nothings really change. it still shake A LOT...



so, if anyone has had this problem... can you share your experience,



incase you ask why it took me a month to start doing something about it, well i work 10 minutes away and the most i get to do with the ST is 40mph.... i just noticed that i still have a bad shake cuz i went to the inlaws for halloween....



anyway... appreciate your help....

guess i really have to take this one to the dealer eh!....

Mike
 
The bearing in the left side of my rear axle was worn out causing a vibration at 64mph consistantly. Took 2 sets of tires, numerous re-balancing, and a new drive shaft before the problem was located by the dealer.



When I would roll in reverse at about 1-2 mph, I could hear a grinding every time the wheel rotated. When I explained this to the dealer they were able to duplicate my claim and took the axle apart, I guess. Anyway, new parts in the axle and no more vibrating.
 
Mike, There were several issues with drive shafts being out of balance, Rear carriers being out, and even bent axles...

You have to almost us a lift and run the truck in the air, try it with and without the tires on and try other things...

There are ways to do it on jack stands but that can be unsafe..

Todd Z
 
did you put bigger tires on it? your situation is exactly like mine. the SHOCKS are fubar... my truck shook, but not through the wheel.... put on the spare up front, it went away. could be the stuff in the responses above....
 
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STanner; Are you saying the bigger tires can cause this and also wear out the shocks?



I put on the next size bigger tires and new Monroe shocks, I get the vibration over 80mph. and I don't want to wear out the shocks. Mind you I don't drive over 80mph often but i'm just asking?
 
OZ...

I am stating what appeared to happen to mine when i put larger tires on. Anybody on the board will tell you the stock shock ate junk from day one. My hypothesis is that the stock shock are setup to work with the side, profile, type, and weight of the stock tires... I would also look at alignment... HTH
 
The first thing I would do is swap the front tires to the rear and the rear to the front. This will tell you if you have a tire or wheel issue. By doing it one at a time as you presently are, it takes a lot of time and there may be no change as your have not gotten to the affected tire/wheel.



Once you swap them all, if you still have the exact same issue with no change what so ever, then you know for sure you no longer need to look at the tires or wheels.
 
well, thanks guys... i will try rotating tires this after noon..



but mind you that i had already put the spare tire on there and still have shaking feeling.

also as stated it only happens pass 60...



well let you guys know what happens...
 
are the tires cupping r wearing more on one side than the other? Mine were wearing on the right side, inside edge of the tire, I had vibration like you are describing, and I finally replaced the front wheel bearings. It got rid of the vibration for the most part (still have a little due to the wear on the tires).



Yes, it felt like the vibration was coming from the r/r tire, but it is in the same location and it is dramatic how much the vibration went away with new wheel bearings in the FRONT.



Of course, now I have a "growl" when stopping (only from 15 mph to 0) that I have to investigate (not sure if it's the brake pads or wheel bearings, or just tire noise)



 
You either didnot get your tires balanced correctly, or you have one or more tires that are cupped or worn out of round.



According to Ford, the drive shaft issue is supposed ot only occur at speeds above 70 MPH.



Look at the wheel weights. If you have more than 1.2 OZ on any one tire, you probably have the heavy side of the tire mounted on the heavy side of the rim. That can lead to a lot of balancing problems. Just bread the bead on the tire and rotate it 180-degrees and reinflate and rebalance.



It check for tires worn out of round, you will need a dial indicator to measure the runout on the tread. Tires worn out of round can be caused by bad shocks or damaged tire cords from hitting potholes, etc.



...Rich
 
According to Ford, the drive shaft issue is supposed ot only occur at speeds above 70 MPH.



well this pretty much explains my vibration then, mine vibrates like crazy from about 75 on up.



anyone have an idea on what it costs to balance the shaft?



 
Rich, it's a TSB depending on when yours was made. They may replace it with an aluminum one if that's not what you have.
 
Jeff,

mine is a 01 job 2, so with ford the TSBs are a no charge

item?



reason i ask is with Dodge ( my last truck ) they charged for

all TSBs and stated that it was for service information only as

a starting point to find problems.
 
RichM, TSB's will cost you money, they are just an Technical Service Bulletin to tell Ford how to fix a problem. Only recalls are free. It will be cheaper to get it balanced somewhere that works on driveshafts compared to buying the new aluminum driveshaft.
 
Olaf,

thanks for clarifying,once the weather breaks for good here in the

northeast i will have to yank it out one day and get it balanced.
 
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