Your car’s steering system enables the car to tum; its suspension system smoothes out the ride. It’s that simple-and that important. Things can go wrong, however, making the ride rough or steering difficult or dangerous. In either of those cases, it’s time to repair. Many types of steering and suspension systems have been used to control cars. Until recently, most cars used pitman-arm steering, which passed the steering wheel’s rotation to a lever (pitman arm) that moved side to side. Many of today’s cars rely on rackand-pinion steering, which uses meshed gears to control steering. Older cars use mechanical suspension that relies on springs and shock absorbers, but newer cars use hydraulic cylinders called struts. All these components are covered in this article. Whether you do these repairs yourself or have them done for you, understanding what’s involved will make you a more savvy car owner. With proper care, your car’s steering system should give you 80,000 to 100,000 miles of smooth turns.
Why Won’t My Car Turn Where I Want It To?
Here are some guidelines for troubleshooting steering and suspension systems. Don’t worry if you’re not sure what all the terms mean; they are covered later in this article.
- If your car’s power steering growls when you try to tum, first check the power steering booster fluid level. Then, if necessary, repair the power steering unit.
- If your car makes a high-pitched squeal, check the drivebelt on the powersteering unit for slippage.
- If your car shimmies, check tire pressure and inspect the tires to make sure they are all the same size and aren’t damaged. Then check for worn tierod ends and lower balljoints in the steering system. That should control your car’s urge to dance down the street.
- If it’s difficult to steer your older car, lubricate the steering system’s zerk fittings to see whether that solves the problem before replacing parts.
- If your car leans hard on comers, check the stabilizer and struts for loose parts and wear.
Stopping Arguments Between Your Wheels
All right you wheels, let’s get some cooperation going. It has to hurt if the left wheel always wants to go right, and the right wheel always wants to go left. Teamwork! Grab your car care toolbox , Chances are you don’t have the tools and equipment in your garage to accurately align your car’s wheels. You’ll probably take it to a specialist who can do the job for you. Even so, understanding why and how wheels are aligned can help you better understand your car and help keep you from getting ripped off. And it will motivate you to keep them aligned. You can also check tire wear to discover whether your car’s wheels are aligned properly. Wheel alignment is necessary to keep the four wheels traveling in the same direction. You don’t want the right wheel going straight ahead and the left one trying to make a tum. Think how quickly you would trip if your feet didn’t aim in the same direction. Front wheels must be moved to steer, so they must be aligned. Rear wheels on cars built since about 1980 also may require alignment. Most cars need wheel alignment every 30,000 to 60,000 miles. That’s a lot less often than your kid’s braces need realigning. Maybe you’ve heard the terms toe in and toe out regarding wheel alignment. No, it’s not a dance. The toe is the front edge of the wheel. Toe in means that the front edges of the two wheels are a little closer to each other than the heels or backs of the wheels. Toe out means the front edges are farther apart than the back edges.
Caster is the tilt of the steering connection to the wheel. Camber is the inward or outward tilt of the wheel’s top. The point to wheel alignment is that each car was designed to operate best with specific alignment tolerances. If the wheel alignment isn’t within its tolerance, tires wear unevenly, the car can be harder to steer, and stress can be put on steering components, making them unsafe and causing fuel mileage to suffer. Sounds expensive. Front-wheel-drive cars have different wheel-alignment specifications than rearwheel-drive cars. The same is true of front-engine and rear-engine cars. Your car’s owner’s manual and service manual will give the manufacturer’s wheel-alignment specs. Alignment is an adjustment to keep parts in the correct relative position, such as the alignment of a car’s wheel and suspension system.
Here are some tests you can make to ensure that your car’s wheels are aligned properly:
- Run your hand over the tire tread from the outer edge to the center and then to the inner edge. The surface should feel equally smooth in both directions. If the surface is rougher moving from the inner edge to the center, the wheel may have too much toe out. If the surface is rougher moving from the center to the outer edge, the wheel may have too much toe in.
- Wear on the outside edge of tires usually means that the camber isn’t set properly. >- Wear on both inside and outside edges of tires usually means that the tire is underinflated.
- Wear in the center of tires usually means that the tire is overinflated.
Suspension and Your Car
Your car’s suspension system includes a shock absorber, a stabilizer bar, leaf springs, a suspension arm, and/or MacPherson struts.
These parts wear out with use and need to be replaced. Here’s the lowdown on what each of them does:
- Shock absorber: A tranquilizer; alternatively, a mechanical cylinder that dampens a wheel’s up-and-down movement caused by bumps in the road.
- Coil spring: A circular steel spring used to minimize up-and-down motion.
- Leaf spring: A group of flat steel springs used to minimize up-and-down motion. >- MacPherson strut: A Scottish dance; alternatively, a component of most front- wheel-drive cars that combines the coil spring and shock absorber into one unit; named for an engineer at Ford in England-really!
- Stabilizer bar: A tavern with seat belts on the bar stools; alternatively, a bar linking the suspension systems on two wheels (front or rear) to stabilize steering or turning.
- Independent suspension: A suspension system that allows two wheels on the same axle to move independently of each other.
How often do the parts in your suspension system need to be replaced? Older cars may need new parts every 25,000 miles, but newer cars could go as many as 100,000 miles before needing parts replacement. Much depends on the car’s design as well as how it is driven. Heavy loads and rough roads wear down suspension parts faster. Because wear to suspension parts is gradual, you might not notice how far components have deteriorated. Steering becomes more difficult. The car doesn’t corner as smoothly. Lots of passengers or heavy packages make the car sag more than it did. You can replace parts as recommended by the manufacturer, or you can test and visually inspect them using your car’s service manual.
To replace suspension parts, follow these steps:
- Find out what suspension parts your car has. A stabilizer bar buffers side-to-side motion. Shock absorbers and coil springs dampen up-and-down motion. A strut combines the shock absorber and coil spring. Front-wheel-drive cars have suspension arms on the rear wheels.
- Jack up the car and place safety stands under the wheels.
- Cars with independent front suspension have a stabilizer bar. Stabilizer bars don’t wear out; the rubber mountings, called bushings, do. The stabilizer bar and bushings are bolted to the underside of the vehicle between the right and left wheel suspension systems. Replace the bushings by removing the brackets holding the bar in place, removing the bushings, and replacing them. Stabilizer bar bushings are sold in sets at larger auto parts retailers.
- Shock absorbers are installed inside the coil spring at each wheel. Shock absorbers can be replaced by removing the bolts at the top and bottom that connect them to the suspension system. Be sure to follow the manufacturer’s instructions because shock absorbers and springs are under tension and can injure you if they are not removed properly.
- Struts are shock absorbers integrated into the coil spring. Remove the fasteners at the top and bottom that connect them to the suspension system. Your car’s service manual or an aftermarket manual tells you exactly how. Don’t try to disassemble a strut. Replace it as a unit.
- Many cars have upper and lower suspension arms that allow the wheels to move up and down independently of each other. These arms typically don’t need replacement, but the rubber bushings on which they are mounted do. To replace them, first locate and inspect them using the service manual. Most require that you loosen and remove a bolt on which the bushing is mounted.
- Tell at least two people on the street about your experiences repairing your car’s suspension system until tears come to their eyes.
The Steering Committee
A steering system (see the figure showing steering systems) uses a steering gear and rods to transfer the turning of the steering wheel to the front wheels. Steering gears usually last as long as the car, but some of the connecting components need replacement along the way. Also refer to your car’s service manual for specific information on fixing your car’s steering problems. As always, make sure you install safety stands under your car before working there. Refer to your car’s service manual for specific information on making repairs to the steering system.
Steering systems are typically repaired following these steps:
- Inspect, adjust, and, if necessary, replace tie-rod ends. Tie rods connect the wheels to the steering unit. The ends of these rods must be free to move with the movement of the steering system. They wear out. If they are worn or damaged, replace the tie-rod ends with ones from an auto parts retailer. Mark the exact location of the old ones so that the new ones can be installed in the same position and require little or no adjustment.
- Check, adjust, and, if necessary, replace the steering gear unit. Many steering gear systems offer adjustments that can be made with a wrench and screwdriver while following instructions in the service manual. If replacement is needed, the steering wheel and column may need to be removed first. Each car is different, so check the manual for specific instructions.
- Test the repaired steering system by driving to some friends’ houses to tell them all about your repair experiences. It helps if they’re trying to watch a big football game.
When the Steering Needs a Boost : Some cars have a booster that uses hydraulics to make turning the steering wheel easier. Most power steering booster systems use a pump turned by the engine’s crankshaft to circulate the hydraulic oil or fluid.
To repair power steering systems, follow these steps:
- Check the power steering hoses for leaks or damage. A small leak can slowly drain the system of hydraulic oil and make turning the steering wheel difficult. Find the steering gear box (near the end of the steering column) and the power steering pump (on the front of the engine, driven by a belt). Locate the hoses running between the two units and check them for leaks and loose fittings. Replace them as needed with identical replacement parts.
- If the power steering pump leaks or is noisy and must be repaired, loosen the bracket that maintains belt pressure, remove the drivebelt, siphon fluid from the reservoir, and then remove the pump and reservoir. Have the unit rebuilt or replaced and reinstall it.
- If power steering fluid must be replaced or the reservoir is dry and fluid must be refilled, make sure you remove air from the brake system. Otherwise, air in the brake lines can make braking more difficult. Check your car’s manual for specific instructions. In many cases, air can be removed from the power steering system by running the engine to operate the pump, removing the reservoir cap, and then turning the steering wheel fully to the left and then to the right a few times. Remember to replace the reservoir cap.