Alignments, Tires and Balance

By Dave Trux

More than once a week, we get a customer asking for an alignment. When probed as to why, more often than not the answer is, “My car is shaking at xyz speed.” The simple answer is that an alignment will not cure a wheel shake. As technically advanced as a BMW is, the effects of an alignment are still the same as any other car.

What an alignment will cure is uneven tire wear and in some cases a pull to one side. There are 3 major alignment adjustments: camber, caster and toe. Of these, only two will cause tire wear and only one of them will cause a pull.

Camber and toe will cause tire wear in very distinct patterns. Caster will only cause a car to drift to one side or another.

Toe is how much of a difference there is between the tread in front of and behind the tire. If the wheels are toed in, the tires will wear on the outside inch or so and across the tire you’ll encounter a fish scale effect. If the wheels are toed out, the tires will wear on the inside inch or so and across the tire you’ll encounter a fish scale effect.

/ \ = toed in

\ / = toed out

Balance issues and loose front end parts are what cause a car to shimmy or shake. Typically, if the car shakes at a certain speed and then goes away, it’s either an out of round tire or loose front end parts. The wheel, at that certain speed will reach its resonant frequency and begin to shake. When you increase road speed, the resonant frequency is passed and the shaking goes away.

A shake that begins at a certain speed then gradually gets worse is most likely the common wheel balance issue. If the tires are in good shape, we spin them up and re-balance them properly. BMW’s are finicky when it comes to alignment and balance issues. It’s why we have invested in only the best Hunter alignment and tire equipment. We do not farm any of it out as our desire is to deliver the car in perfect condition. We simply do not trust a “tire shop” to align one of our customers BMW’s.

Safety First for our Newest Drivers!

By Walter Ford

With kids now back in school, parents have good reason to be concerned with safety. Safety is especially important for our new drivers, so now is a good time to have an overall safety check of your vehicle before you hand over the keys. First of all, a teenage driver is a new driver, so they are inexperienced. They tend to be more inattentive when compared to more seasoned drivers. You want to make sure that your car is in good overall health. Kids have enough challenges operating a car on a public highway, so you don’t want to throw them any curve balls. A good place to start is to make sure that the brakes and tires are in really good condition.

When inspecting your brakes, be sure to have plenty of life on your brake pads and the rotors are in good shape. You really want to check the rotors to make sure they don’t have any ridges, even though the pad does not run across the whole face of the rotor. You want to look at the edge of the rotor, because that’s a clear indication of how much has been taken off. With most cars nowadays, the old rotors are tossed out and new ones are put on. They are relatively inexpensive now compared to what they used to be. As for the brake pad itself, you probably want 3/32 of an inch or more. The issue with the brake pads is the more material it has, the more heat can dissipate, so the less likely it will stay under pad in stopping conditions.

When you inspect your tires, make sure you have a decent amount of tread on them, especially now that the rainy season is here. In the old days, people used a penny as a guide and measure to the top of Lincoln’s head, which is 2/32 of an inch. In the state of California, you’re allowed to have a minimum of 2/32 of an inch on your front steer axle. The rear axle must be a minimum of 1/32 of an inch of tread. A word of caution is that these are minimums.

Most new cars now tend to be a little sportier, with tires that are more of a summer tire. So, I would take my car to someone who really knows what they’re doing and ask if the tires will be good for the winter time. If you are driving a vehicle with a sports package, you’ll likely have a tire that is a performance summer tire. If you only have 2/32 of an inch, it’s pretty useless in the rain. So, be sure to examine not only the trend depth but also the tread design. 

Can your car stand the heat?

By Walter Ford

An AC service starts out with a function test to make sure that the fan operates at each speed setting and the temperatures of the air vent is also measured. In cases where we don’t get adequate temperature, we perform a vacuum test and draw all the freon out of the system. The vacuum test is our way of making sure that the system is not leaking. It is against EPA regulations to put refrigerant into a system is. Basically you are just pumping it back out into the environment.

It’s more important nowadays with new refrigerants because they are not as efficient, they have to operate at much higher pressures. We find that because of the higher operating pressures, it’s even more important to make sure the system is sealed and working. Refrigerant is not the only thing in the system; there is also oil. Oil is used to lubricate the pump. If you just keep adding refrigerant and not drawing it down making sure it’s not leaking and doing a proper service, you could burn up your pump because you don’t have adequate oil in your refrigerant system.

It’s a good idea to have your entire AC system inspected before the weather gets any hotter. Make sure your mechanic does a comprehensive function test. If the system doesn’t function properly, the next step is to go back and perform a vacuum test. If they don’t do that test and merely add more refrigerant without adding additional oil, then you will likely end up with a system that will fail because the pump could burn up.

We offer a free basic function test and inspection. Based on the results, we’ll determine whether we will move forward with a vacuum test. If we do see a leak, then we will add dye to the system and use an infrared light to see where the leak is located.