anyone know wtf they are for?

 

to balance out the 4 corners of the car. if one tire wears unevenly, they have to compensate on the other 3 wheels to make up for that. know what i mean? your tires go out of balance, your steering wheel starts to shake, you get pissed, and your tires are being worn unevenly all in the process. so they throw weights on your wheels to even things out.

 

i have weights on 3 of my wheels

 

meaning the oddball that isn't weighted wore wrong. not to say that it'll KEEP wearing wrong, but initially, could've been a minor minor "outta wack" install job on a tire or something. nothing to be worried about.

 

MOst of the time wheels are individually spin balanced, and weights are install on the inside and outside lip of the wheel to properly balance it. You may want to have your wheels re-balanced if you're curious about it.

 

I've had two different wheels on two different occasions not need any weight, the wheel and tire were already in balance. Then, I've had wheels/tires that need weights in two different places.

 

wheel weights are for tire balancing...
dont take them off...
Maintaining the tire balance on your vehicle is critical to receiving satisfactory service from your tire investment. In addition to a providing a smooth ride, balancing is a key component in tire wear.
When a tire is mounted onto the wheel, two slightly imperfect units are joined to form an assembly weighing forty pounds (this is the average for cars). The chances of this assembly having absolutely precise weight distribution about its radial and lateral centers are virtually impossible. Remember that all it takes is half an ounce of uneven weight distribution for a vibration to be felt. The illustration below shows how an imbalance creates vibration.
The static imbalance creates a hop or vertical vibration. The dynamic imbalance creates a side-to-side or wobbling vibration. Most assemblies have both types of imbalance, and require dynamic balancing to create even weight distribution. The balancing system directs a technician to place counter weights on the rim's outer surface to offset the imbalance. When the balancing system tests for virtually perfect weight distribution, the assembly is in balance and will not vibrate. Your tires will ride smoothly and wear evenly (with regard to balance).

 

wheel weights are for tire balance ... dont take them off...

When a tire is mounted onto the wheel, two slightly imperfect units are joined to form an assembly weighing forty pounds (this is the average for cars). The chances of this assembly having absolutely precise weight distribution about its radial and lateral centers are virtually impossible. Remember that all it takes is half an ounce of uneven weight distribution for a vibration to be felt. The illustration below shows how an imbalance creates vibration.

The static imbalance creates a hop or vertical vibration. The dynamic imbalance creates a side-to-side or wobbling vibration. Most assemblies have both types of imbalance, and require dynamic balancing to create even weight distribution. The balancing system directs a technician to place counter weights on the rim's outer surface to offset the imbalance. When the balancing system tests for virtually perfect weight distribution, the assembly is in balance and will not vibrate. Your tires will ride smoothly and wear evenly (with regard to balance).