Major Tire balancing problem

[steam_mill]

I have a 2000 Subaru Outback Wagon Limited .<br /><br />At the 72K km service, the brakes were checked and 'serviced'. Tires<br />were rotated and balanced.<br /><br />Car never ran smoothly again. At 110 Kph (65 mph), I get a wheel shimmy. Back to the dealer it went. He rotated balanced etc. <br />Conclusion, tires were shot. Balanced as best he could but told me<br />the tires were needing replacement anyway.<br /><br />At 80K, replaced with Michelin Hydroedge. Shimmy/vibration were still<br />there but less. Back to the tire dealer. The dealer was great (Kipling<br />Tire in Toronto).<br /><br />Went back to tire dealer and to make a long story short, they balanced all tires 5<br />times. Shimmy still there. Thought maybe the tires were bad.<br /><br />Put on a brand new set of Michelin symmetry. Same problem. Put the<br />Hydroedges back on.<br /><br />Went to dealer thinking a bad bearing/cv joint etc. Car checks out<br />perfect. Tire changes were all torqued with a torque wrench. <br />Different rims at different points on the car. Car does not vibrate<br />only sterring. All drivetrain components appear to NOT be vibrating.<br /><br />Everybody is at their wits end. I like the car but I can't drive it like this.<br /><br />Tire dealer went as far as to balance rim without tire and put tire heavy spot against rim heavy spot etc.<br /><br />Ideas?

 

[Skinnywater]

Re: Major Tire balancing problem

Prior to the 72km service was there any vibration?<br /><br />Is there a vibration as you apply the brake?<br /><br />Has the steering rack been checked for proper mounting?<br />The steering shaft joints for wear?<br />Subframe, motor mounts, differential mounts?<br /><br />Are there any other changes?<br /><br />Specifically, what did brakes "serviced" mean?

 

[Spidybot]

Re: Major Tire balancing problem

General Systematics:<br /><br />The problem has to come from something that rotates when the car moves.<br /><br />Drive shafts<br />Bearings<br />Tires<br />Brake discs<br />Rims<br />Wheel covers<br />Vibration can increase or be ephasized by worn joints or incorrectly torques or badly worn/defective shock absorbers. Some of these seems to be out of the question in your case but should be kept in mind anyway.<br /><br />The items mentioned may suffer from not being balanced and/or not being completely round. A rim or tire that is oval (maybe due to internal breakage) will never run smooth, regardles of 100% correct balance. Try turning the wheel slowly either on the car (jacked up) or in the balancing machine and watch closely for thread run in/out and up/down. Even watch the rim edges.<br /><br />As your car does this even with brand new tires, some of the other items must be involved.<br /><br />Certain tire shops have balancing equipment to do the job while the wheel is fitted on the car. Not as accurate as the traditional wheel balancer, but will cope with balance issues that involves mixed parameters from more moving parts.<br /><br />On the brake/bearing issue one must make certain, that all moves free and that the brake's work smooth and even on all wheels.<br /><br />A disk that has one point where it brakes harder feels like a shake when brakes are applied and will, over time, result in a flat spot on the tire as the extra braking will affect the same spot over and over.<br /><br />One point that often is missed concerns the cleanlines of the hub surface where the rim meets the hub. Even the slightest dirt here, at the center of the wheel, will make a big difference at the circumfence.

 

[JB]

Re: Major Tire balancing problem

I had a similar problem on a Ford Bronco ('68, bought new) many years ago. New tires, new rims, balancing and rebalancing seemed to do no good.<br /><br />Factory guru was sent out. He realigned the front end with added caster and added a damper to the steering, which finally cured the problem. I think the damper became standard on later Broncos.<br /><br />I know there are big differences in live axles on coils with drums and the struts with disks on your Subaru, but it is something to look into.<br /><br />Because this began with a "brake service" I am also thinking like Skinnywater and UU. . . a flaw in a rotor or incorrect mounting of brake system parts.<br /><br />Good luck.

 

[DJ]

Re: Major Tire balancing problem

I would be willing to bet, it's the brake rotors.

 

[ehenry]

Re: Major Tire balancing problem

I had a similar problem with my truck with a set of new tires. What we ended up doing was turning the tires 180 degrees on the rims and rebalancing them and that cured the problem. If your tire shop will let you, watch the tread face of the tire while they are spinning it on the balancer, if you see a jump in the tread, rotate the tire 180 on the rim and spin it again see if the jump goes away. If not get another tire.

 

[mikecjn]

Re: Major Tire balancing problem

I had a similiar problem with my Ford Taurus after a vehicle inspection. The car developed a shimmy in the rear.<br /> Turned out that when the garage removed my rear drums to check the brakes they cracked a small piece of the drum when the were tapping them off. After they rotated the tires to see if it would change anything they finally saw the drum and replaced it.

 

[DJ]

Re: Major Tire balancing problem

I still think it may be the rotors. Todays rotors are very sensitive to lug torque. <br /><br />However, any good tire shop should be aware of the term "road force dynamic". Alot of that has to do with the relationship of the tire and the rim. High point vs. low point indexing.

 

[Pete30]

Re: Major Tire balancing problem

I had a similar problem on a Jeep Cherokee, the mechanic told me I had a broken motor mount.

 

[JB]

Re: Major Tire balancing problem

I think you may make progress on this if you redecribe it as a shimmy problem rather than a tire balance problem.<br /><br />A shimmy is not the same thing as a hop and can be caused by a lot of things that have nothing to do with tires..<br /><br />Good luck.

 

[steam_mill]

Re: Major Tire balancing problem

Just an update:<br /><br />Problem was a rotor not seated properly. Dealer reseated the rotor and vibration went away.<br /><br />What a pain in the a$$.<br /><br />Joe

 

[LubeDude]

Re: Major Tire balancing problem

Glad you finally got it figured out, those things can be such a PIA!!<br /><br />Had a vibration on the wifes RX/7, Finally rurned out to be a separated tire!