Monthly Archives: September 2016

Know More About How Often Should Tires Be Balanced

Smooth driving is a balancing act that requires getting the wheels and tires to rotate at high speeds without vibrations. That’s not a slam dunk; a dirty little secret about wheels and tires is that they usually aren’t perfectly round, even when brand new. What’s more, their weight often isn’t evenly distributed, so they’re heavier in some spots than others.
Either issue can cause annoying vibrations. Out-of-balance tires can also cause rapid tire or suspension wear, so it’s not just about ride comfort.

That is why when new tires are mounted on wheels they’re spin-balanced to detect vibrations. Some vibrations can be eliminated by rotating the tire on the wheel so the heavy or “high” spot is in a different location that better matches up with the wheel. Small weights are attached to the wheels with adhesives or clips to counteract the heavy spots and provide a smooth ride. Over time, though, the weights can fall off. If that happens to a front wheel, you may feel vibrations through the steering wheel that typically become more pronounced as vehicle speed increases.

Many tire dealers include free lifetime rotation and balancing with new tires (something you should ask about before buying). Tire rotation is when the vehicle’s tires are removed and reattached at a different position to ensure they wear evenly, which should be done every 5,000 to 7,500 miles on most vehicles, or according to the automaker’s recommendation.

Many consumers neglect the balancing part and have their tires rotated only periodically. If balancing was included with the tires, it would be wise to remind the shop to check the balance at the same time. Even if balancing costs extra, it’s a good idea to have it checked at least every two years, or more often in areas where roads are not well-maintained.

Vibrations can also be caused by a bent wheel, a damaged tire (which won’t be fixed by balancing), worn suspension parts or worn wheel bearings, so balancing the wheels and tires may not eliminate all vibrations.

Tires and wheels are balanced before being attached to the vehicle by spinning them on a balancing machine that identifies heavier or stiffer spots that cause vibrations. Some tire dealers and repair shops use “road force” balancing machines that simulate the weight and forces applied to tires and wheels during driving conditions. They say this method provides more accurate and detailed readings that allow more precise balancing.

More Information About Brakes Squealing

If you’re lucky, the squealing (or squeaking) noise that your brakes make when you first drive your car in the morning, particularly after rain or snow, is just surface rust being scraped off the rotors by the pads the first few times you apply the brake pedal, or the result of moisture and dirt that collects on the rotors, including from condensation caused by high humidity. If it goes away after a few brake applications, no worries.

If the noise persists most times or every time you apply the brakes or stays on continuously while you’re driving, the cause is more serious — and the fix will be more expensive.

A continuous high-pitched squeal while you’re driving is usually the sound of a built-in wear indicator telling you that it’s time for new pads. As the pads wear down and get thinner, a small metal tab contacts the rotor like a needle on a vinyl record to warn you it’s time for new pads. (Some wear indicators may work differently and engage only when you apply the brakes.)

Other squeals and squeaks will require a brake inspection to diagnose, and may require cleaning, lubrication or adjustment, and possibly new parts. Most brake noise is caused by worn or loose parts.

For example, an unevenly worn rotor (often referred to as “warped”) won’t let the brake pads press flat against the rotor when you apply the brakes, and that can create vibrations that generate noise. Likewise, an unevenly worn pad won’t press tightly against the rotor and may chirp. Another possibility is that the pads are loosely mounted, or the shims that hold them in place have corroded or become loose.
And then there are the pads themselves. Some mechanics warn that bargain-bin pads are more likely to be noisier than higher-quality, more-expensive pads. In addition, loose or sticking calipers can contribute noise.

Because there are several possibilities, and because brakes are a crucial safety feature, it is best to have a pro diagnose noise.

A grinding sound usually means that the pads have worn away, and now the backing plates on which they were mounted are being squeezed against the rotor. This metal-to-metal contact means that you will need to replace the rotor as well — and that you probably ignored some earlier warning signs of brake wear.

When The Best Time You Should Change Engine Coolant

For some vehicles, you’re advised to change the coolant every 30,000 miles. For others, changing the coolant isn’t even on the maintenance schedule.

For example, Hyundai says the coolant (what many refer to as “antifreeze”) in most of its models should be replaced after the first 60,000 miles, then every 30,000 miles after that. The interval is every 30,000 miles on some Mercedes-Benz models, but on others it’s 120,000 miles or 12 years. On still other Mercedes, it’s 150,000 miles or 15 years.

Some manufacturers recommend changing the coolant more often on vehicles subjected to “severe service,” such as frequent towing. The schedule for many Chevrolets, though, is to change it at 150,000 miles regardless of how the vehicle is driven.

Many service shops, though — including some at dealerships that sell cars with “lifetime” coolant — say you should do it more often than the maintenance schedule recommends, such as every 30,000 or 50,000 miles.

Here’s why: Most vehicles use long-life engine coolant (usually a 50/50 mixture of antifreeze and water) that for several years will provide protection against boiling in hot weather and freezing in cold weather, with little or no maintenance. Modern vehicles also have longer intervals between fluid changes of all types partly because environmental regulators have pressured automakers to reduce the amount of waste fluids that have to be disposed of or recycled.

Coolant can deteriorate over time and should be tested to see if it’s still good, as it can be hard to tell just by appearances. Even if testing shows the cooling and antifreeze protection are still adequate, antifreeze can become more acidic over time and lose its rust-inhibiting properties, causing corrosion.

Corrosion can damage the radiator, water pump, thermostat and other parts of the cooling system, so the coolant in a vehicle with more than about 50,000 miles should be tested periodically. That’s to look for signs of rust and to make sure it has sufficient cooling and boiling protection, even if the cooling system seems to be working properly. It can be checked with test strips that measure acidity, and with a hydrometer that measures freezing and boiling protection.

If the corrosion inhibitors have deteriorated, the coolant should be changed. The cooling system might also need to be flushed to remove contaminants no matter what the maintenance schedule calls for or how many miles are on the odometer. On the other hand, if testing shows the coolant is still doing its job and not allowing corrosion, changing it more often than what the manufacturer recommends could be a waste of money.

Know More About Some Radiator and Cooling System Problems

If steam is pouring from under your hood, a temperature warning light is glowing bright red on your dashboard or the needle in the temperature gauge is cozying up to the High mark, it’s time to pull off the road and shut down the engine before it fries from overheating.

Any indication of overheating is a serious matter, so the best course of action is to shut down the engine to prevent further damage. Driving a car with an overheated engine can warp cylinder heads and damage internal engine parts such as valves, camshafts and pistons.

Even letting the engine cool for an hour and topping off the radiator with a 50-50 mix of antifreeze and water may not fix what’s wrong. Here are some reasons an engine will overheat:

– The coolant level could be extremely low, because of long-term neglect or because a leak has developed in the radiator or radiator hoses. Coolant circulates inside the engine block to cool it, and the leak might be in the block, or from the water pump or heater hoses. Old coolant loses its corrosion-inhibiting properties, allowing rust to form and ultimately causing damage.
– The thermostat that allows coolant to circulate may be stuck in the closed position or a clog may have developed, perhaps from debris in the cooling system.
– The engine cooling fan has stopped working or the radiator’s cooling fins are clogged with debris so that the air flow that reduces the coolant temperature is restricted.
– The radiator cap has gone bad and no longer maintains enough pressure in the cooling system, allowing coolant to boil over (engines normally operate at about 210 to 220 degrees Fahrenheit).
– The head gasket that seals the gap between the cylinder head and engine block may have failed, allowing coolant to leak inside the combustion chambers. The steam should be visible coming out of the exhaust system.
– The water pump has stopped working or the belt that drives it broke or is slipping and not pumping enough coolant.
– You’ve been towing a 5,000-pound trailer with a vehicle equipped to tow only 2,000 pounds, exceeding the vehicle’s cooling capacity. (You probably also strained the transmission.)

Checking your engine coolant level in the overflow tank on a regular basis can help avoid disasters. If you have to keep topping off the coolant, that’s an indication of a small leak that should be taken care of before it becomes a major one. Having your coolant tested and the entire system inspected by a mechanic every couple of years is an even better way to prevent cooling system disasters.