Byprodrive

iTrader: (1)

[QUOTE=Och;8516369]Vibrations coming from an unbalanced tire can easily wreck havok on the rest of the drivetrain, and cause damage to driveshafts.

I didn't read you entire post, so you might have already covered this, but I'd like to make a suggestion to anyone concerned with potential vibrations.

1) Do not ever buy non factory rims. Aftermarket rims usually have a large hub bore, so they never sit tight on the hub, and are instead relying on the lugs to be centered - and as a result they are usually never properly centered, and putting extra stress on wheel studs. Constant vibrations are almost guaranteed.

I would say don't use non-hubcentric wheels designed for your vehicle application.

Diesel350

It took it back had it tested for imbalance and they did not see any imperfections. They also mounted the wheel on the back. Just kind of frustrated right now as it seems my only option is to buy aftermarket wheels and tires.

mmarshall

Thanks. Glad it helps.

mmarshall

Thanks.

If the vibration is in the seat, it's more likely to be either in a rear wheel or, as you noted earlier, the driveshaft, rather than in a front wheel. As I said in the article (you may not have read that part), out-of-round tires can be made to balance perfectly, yet still cause shimmies or vibrations in the car. I'd check the runout on the rear tires. If possible, look at them on the balance machine while they are still spinning, and see if you notice any up/down hop or side-to-side motion. If so, it may be time for new tires if doing a 90 or 180 on them doesn't work. If the problem isn't traced to wheels or tires, then, yes, the driveshaft or suspension/steering components would be next on the list.

Byprodrive

iTrader: (1)

On the car highspeed balancing is a disappearing that can solve many problems.
The whole wheel/tire assembly is spun at varying speeds as high as 120mph in my experience.
This balances the assembly under actual operating configuration, taking into account brake rotors,axles,lugnuts, everything that spins with the wheel. This will cost more than twice as much as off the car balancing & the wheel must be replaced in the same position on the wheel studs if removed. This process is often needed for 80mph+.
Another good reason to use oem quality replacement rotors, axles, wheels,etc.

mmarshall

That can screw up the differential/final-drive unit, though, can't it?...or the center differential in car-based AWD?

mmarshall

Excellent point. Not only that, but they might not have the necessary fittings for tire-pressure sensors on newer cars.

mmarshall

Most automakers, today, don't give us much of a practical choice. Low-profile 35-55-series tires have pretty much become the norm on everything except some trucks and SUVs.

Yes, you still get good quality with Michelin, but some others (especially Contenental) are catching up. Michelins, however, sell so much on their past (and, to an extent, present) reputation that some tire shops won't discount them when they have tire-sales on other brands.


Agreed. Hunter makes some good equipment.

mmarshall

The tire, of course, has to have at least a 120 MPH or more speed rating if that is to be done safely. Otherwise, it could (?) fly off the rim, though most tires today have somewhat of a safety-margin built into their official speed ratings.

Och

iTrader: (3)

I wonder what will happen with all the new cars that have electronic steering, where the steering wheel has no mechanical connection to the drivetrain and steering rack. As such, you might not even be able to feel any vibrations, which can be potentially dangerous?

mmarshall

In some cases, you might feel them in the frame or car seat like you sometimes do with rear-wheel problems, especially with the firmer suspensions and stiffer low-profile tires on today's cars.

Actually, although some systems may be off in the future where an all-electronic steer-by-wire system completely by-passes any mechanical connections, those systems, for the most part, don't yet exist in today's production cars. The only (close) exception is in one of the new Infiniti sedans (the Q50, I think), that has an optional electronic system that breaks a direct mechanical connection to the rack. But, today, even so-called "electric" steering systems simply drive the power steering pump with an electric motor instead of a hydraulic pump/fluid. Otherwise, the basic system is more or less the same as conventional hydraulic units....but usually with somewhat less steering/road feel. The electric steering-pumps are claimed to (slightly) increase fuel economy by causing less engine drag, but I'm not convinced.

mmarshall

Also, one thing I forgot to mention in my opening post. Some shops might try and convince you (as a Chrysler Service-Manager did with me years ago) that front-end shimmies are inevitable with FWD/AWD because of all of the spinning hardware feeding into the front wheels/tires (transmission, final-drive units/differentials, CVT joints, etc.....)

Don't fall for that line, That simply is not true, IF the drivetrain components were engineered and assembled properly.

Byprodrive

iTrader: (1)

Some vehicles do require different methods to spin the wheel & tire up to speed. If you have the drive over rack made for tire changing they can spin the tires with the engine. Choose a shop that has the experience to do this safely.

chikoo

The worst offender has been the last Generation Honda Odyssey.

http://www.odyclub.com/forums/9-prob...vibration.html

mmarshall

I know that, in some jurisdictions with roller-wheel vehicle emissions tests (including my own D.C. area), car-based AWD vehicles are exempt by the EPA from the rollers because they can ruin the center-differentials. Instead, they just stick a sniffer-rod into the exhaust pipe and run the engine to 2000 RPM with the vehicle in neutral.