Answer: No, it simply means the vehicle manufacturer was too cheap to design adjustable suspension components when it engineered your car. When a car maker designs a car, engineers and accountants scrutinize each and every component to figure out how they can reduce manufacturing and assembly costs. If a few cents can be saved by leaving out an adjustable camber bolt, caster shim or whatever, they'll do it. They may have great faith in their own ability to build a vehicle that never needs to be aligned or fixed, but we all know from experience that such notions are untrue. So even though a suspension is nonadjustable and shouldn't require any corrections, that doesn't necessarily make it so. Even brand new vehicles can roll off the assembly line with wheels that don't meet their own alignment criteria.

Fortunately, the aftermarket has come up with ways to correct the "mistakes" of the vehicle manufacturers. If the car maker doesn't include provisions for adjusting the suspension, it creates an opportunity for some aftermarket part's supplier to come up with means of making such adjustments possible. These include offset bushings, shims, wedges and other alignment aids. So even though your suspension may have few if any adjustments for things like camber, caster and rear toe (front toe is adjustable on all cars and trucks), there are probably aftermarket alignment aids that allow at least some limited corrections to be made on nonadjustable suspensions.

Answer: The most likely cause is an out-of-balance wheel and tire. But vibrations can also be caused by a tire or wheel that's out of round (excessive runout), "heel-and-toe" wear on a tire, driveshaft imbalance, or even harmonic vibrations in the engine and drivetrain.

Wheel balance: For a wheel to roll smoothly, it must be properly balanced. Balancing the wheel and tire involves spinning at high speed to determine where the "heavy" spots are. Small lead weights are then positioned opposite the heavy spot to counteract the forces generated when the wheel spins. If your wheels have never been balanced, if you've lost a wheel weight, or if you've put a lot of miles on your tires since they were last balanced, wheel imbalance may be causing your vibration problem. The way to find out is to have the wheels rebalanced. If the vibration goes away, you've cured the problem. If the vibration remains, then it's something else. Wheel balance problems can usually be felt in the steering wheel, and grow in intensity the faster you drive. Below 45 mph, you usually don't feel a thing. But by 55 or 60 mph, you feel a steady shake. Most wheels today are balanced using an off-car electronic spin balancers. These machines are extremely accurate and usually do an excellent job of balancing wheels and tires. But because the wheels are balanced off the vehicle, the machine does not take into account any imbalance in the brake rotors or drums. Consequently, you may still have a balance problem even though the wheels have been properly balanced. The cure here is to have the wheels balanced using an "on-car" wheel balancer. Though on-car balancers are hard to find today, and are difficult to use on front-wheel drive and four-wheel drive vehicles, an on-car balancer will compensate for rotor or drum imbalance.

Wheel runout: If wheel balance isn't the problem, the next thing to check would be wheel and tire runout. This usually requires positioning a dial indicator against the center of the tire tread and noting how much runout occurs as the tire is rotated by hand. More than about .050 inch of runout can cause vibration problems. If you don't have a dial indicator, hold a pencil or stick on a block of wood near the center of the tread and observe how much the tread moves in and out as the tire is rotated. If runout is more than the thickness of a nickel, it may be your problem. Runout can be corrected several ways. One is to remove the wheel and remount it on the hub in a different index position (lined up so the lugs go through different holes than before). This may help to reduce runout caused by an off-center hub or a wheel that wasn't manufactured with perfectly centered holes. Another way to correct runout is to dismount the tire from the wheel. A dial indicator can then be used to find the high and low spots on both the tire and wheel. The tire is then remounted on the wheel so the tire high spot lines up with the wheel low spot. This may reduce overall runout to the point where vibration is no longer a problem. If that doesn't work, a "tire truing" machine (if you can find a service facility that has one) can be used to shave rubber off the tire and make it round again. This will reduce the life of the tread somewhat but it's cheaper than replacing the tire and/or wheel, which is the last resort to solving a runout problem.

Heel & toe wear: Some low profile performance tires have a tendency to develop an unusual heel-and-toe wear pattern on the tread. When you look closely at the blocks of rubber, the forward or trailing edges of the blocks will be worn unevenly so the forward edge of one block will be higher or lower than the block that follows it. This rough wear pattern causes a vibration that is most noticeable at speeds above 40 mph. It also produces noise. The wear pattern develops because of the way the tire is built, and the only way to prevent it is to rotate the tires frequently (every 8,000 miles or so). If your tires have this kind of wear pattern, it may be too late to counteract the condition by rotating the tires. Replacing them may be the only way to get rid of the vibration.

Driveshaft imbalance: Vibrations caused by driveshaft imbalance are not very common, especially on front-wheel drive cars and minivans. But it may occur on a rear-wheel drive car or truck if a balance weight falls off the driveshaft. Driveshaft vibrations can also be caused by worn U-joints or a worn or loose center carrier bearing on a two-piece driveshaft. If you've raised the suspension on a truck or sport utility vehicle, it's also possible to create vibrations due to the altered driveshaft angle. U-Joints will produce cyclic vibrations if operated at more than a few degrees off center.

Harmonic vibrations: Vibrations can also be caused by the engine or engine-mounted accessories. A noisy air conditioning compressor, power steering pump, air pump, an out-of-balance engine-driven fan, etc., can all create annoying vibrations. If the vibration seems to vary more with engine speed than vehicle speed, suspect this kind of problem. Check for loose mounting brackets, bolts, fasteners, or physical contact between the accessory and some other component. Many engines also have certain rpm ranges at which they tend to produce more noise and vibration than others. Many newer engines have counterrotating "balance shafts" to help dampen these vibrations. A sudden change in the vibration characteristics of your engine, therefore, may indicate a collapsed or broken motor mount, or a failure of the balance shaft drive gears or chain.

Answer: You need new shocks (and/or struts) if your original shocks (or struts) are worn out, damaged or leaking. Leaking is easy enough to see (just look for oil or wetness on the outside of the shock or strut) as is damage (broken mount, badly dented housing, etc.). But wear is often more of a subjective thing to judge. There are also instances where the original equipment shocks may not be worn, damaged or leaking, but may not be adequate for the job they're being asked to do. In such cases, upgrading the suspension with stronger, stiffer or some type of special shock (or strut) may be recommended to improve handling, for trailer towing, hauling overloads or other special uses.

Shocks and struts do not require replacing at specific mileage intervals like filters or spark plugs, but they do wear out and eventually have to be replaced. How long a set of original equipment shocks will last is anybody's guess. Some original equipment shocks may be getting weak after only 30,000 or 40,000 miles. Struts usually last upwards of 50,000 or 60,000 miles. But when exactly a shock or strut needs to be replaced is hard to say. Because the damping characteristics of shocks and struts deteriorate gradually over time, the decline in ride control often passes unnoticed. So by the time to think you need new shocks or struts, it's usually way past the point when they should have been replaced.

Why replace them? Weak shocks and struts won't necessarily create a driving hazards if you continue to drive on them, but there are studies that show worn shocks increase the distance it takes to stop a vehicle on a rough surface. Increased body sway due to weak shocks or struts can also increase the risk of skidding on wet or slick surfaces.

Worn shocks and struts also increase suspension wear (though marginally) but can have an effect on tire wear. If the shocks are really bad, the tires can develop a cupped wear pattern. The reason why most people decide to have worn shocks or struts replaced, however, is to improve overall ride quality. If you're sick of bouncing and rocking on rough roads, a new set of shocks or struts will firm up your suspension and restore proper ride control. If you're interested in performance handling, you can upgrade to premium "gas" charged shocks or struts. These are charged with high pressure nitrogen gas to help minimize foaming in the hydraulic fluid inside the shock. This lessens "fade" on rough roads and helps the vehicle maintain better ride control when cornering. There are also "heavy-duty" replacement shocks and struts that have larger diameter pistons than stock. These too, provide increases resistance for greater control -- but may be a little too harsh for everyday driving. So some shocks have special valving or adjustable valving that allows the amount of resistance to vary. Another option to consider if you tow a trailer or haul extra cargo are overload or air-assist shocks. Overload shocks have a coil spring around them to increase the load carrying capacity of the suspension (these also tend to ride stiffer than standard replacement shocks). Air-assist shocks have an adjustable air bladder that acts like a spring to carry extra weight. With this type of shock, air can be added on an "as needed" basis when hauling extra weight.

Replacement: Shocks and struts are generally replaced in pairs -- though this isn't absolutely necessary if only one shock or strut is leaking or has suffered damage at a low mileage. Shocks are a popular do-it-yourself item on most vehicles because they're fairly easy to replace. But struts are not. Most struts require a fair amount of suspension disassembly as well as a spring compressor. What's more, the wheels must usually be realigned after replacing a strut. For this reason, you're probably better off letting a professional replace your struts.

Answer: On most vehicles they do. Here's why: MacPherson struts are more than overgrown shock absorbers. They're an integral part of your vehicle's suspension. They replace the upper control arms and ball joints and serve as the steering pivots for the front wheels. When the strut assembly is unbolted and removed from the vehicle, the original alignment of the suspension is lost -- unless the position of the camber bolts and upper strut plate are first marked so they can be reinstalled in exactly the same position as before. But this only works if the same original strut is being put back into the car. If the strut is being replaced because it is leaking, damaged or worn out, the dimensions of the new strut will usually vary enough to cause a change in wheel alignment. So wheel alignment should at least be checked to see if adjustment is necessary (which it usually is). On some import cars, the struts are "rebuildable." The housing has a removable nut that allows the old guts inside to be dumped out and a new cartridge installed. On these vehicles, it should not be necessary to realign the wheels after rebuilding the strut.

Answer: Ball joints are a part of your vehicle's suspension that connects the steering knuckles to the control arms. A ball joint is essentially a flexible ball and socket that allows the suspension to move and at the same time the wheels to steer. Cars and trucks without strut suspensions typically have four of them (one upper and one lower on each side). Cars and minivans with strut suspensions have only two (one lower ball joint on each side). Some front-wheel drive cars also have ball joints on the rear suspension. Like any other suspension component, ball joints eventually wear and become loose. Excessive play in the joint can affect wheel alignment and tire wear. Loose joints can also cause suspension noise (typically a "clunking" sound when hitting a bump). Warning: If a ball joint fails, the suspension can collapse causing a loss of control. So don't put off having a bad set of joints replaced.

Joint inspection: Joints should be inspected before they're greased (since grease takes up some of the slack in the joint). Ball joints are pretty easy to check, but each type requires a different inspection procedure. Use the wrong procedure and you'll get misleading results. The procedure that needs to be used depends on the location and loading of the joint:

Lower load carrying ball joints are found on front- and rear-wheel drive vehicles where the coil spring or torsion bar is on the lower control arm. Joints with built-in wear indicators must be checked with the full weight of the vehicle on the tires on the shop floor or on a drive-on style ramp -- not with the wheels up or the suspension supported by jack stands. No measurements are required if a joint has a wear indicator because internal play is indicated by the position of the grease fitting boss. The boss protrudes about .050 inches on a new joint. As the joint wears, the boss recedes into the housing. The joint is considered "good" as long as you can see or feel the edge of the boss protruding from the housing. But if the top of the boss is flush or below the housing, it's time to replace the joint.

On lower load carrying ball joints without a wear indicator, the joint is checked in the unloaded condition with the wheel raised off the ground and the lower control arm supported by a jack stand. A dial indicator is then used to measure play in one of two directions: sideways (horizontal or radial play) or vertically (axial or up-and-down play). The direction to measure depends on the application (refer to a manual for the exact specs). Sideways play is measured with the indicator positioned against the inside of the wheel rim near the joint. The wheel should be pushed in and out by hand to check sideways play, and lifted with no more than 25 lbs. of force to check vertical play. Many joints allow up to .250 in. of sideways (radial) play, but some allow no play or only .015 in. of play. Always refer to the vehicle manufacturer's specs. Vertical play is measured with the dial indicator positioned against the knuckle stud nut or the joint housing. A joint that has more than .050 in. of vertical play doesn't necessary require replacement because the specs range from zero play to as much as .125 inch of play. The most common mistake that's made here is to use too much pressure on a pry bar or to insert a pry bar between the control arm and knuckle rather than under the wheel. Pry hard enough and any joint may appear to be bad.

Lower follower nonloaded ball joints are found on two kinds of applications: RWD cars where the spring is over the upper control arm, and vehicles with MacPherson strut suspensions. On both applications the lower joint is checked with the wheel raised off the ground hanging free (no stand under the lower control arm). Rock the wheel in and out by hand. A good joint should show no movement.

Upper load carrying ball joints are found on vehicles where the spring or torsion bar is on the upper control arm. Like the lower follower nonloaded ball joints, the upper joints are checked in the unloaded condition with the wheels off the ground -- but with a wedge or block between the frame and upper control arm to support the upper arm. On most applications, any movement calls for replacement. But on some Fords, up to .250 in. of radial play is allowed.

Upper follower nonleaded ball joints are also checked with the wheels off the ground but with the lower control arm supported. Any movement usually calls for replacement.

Joint replacement: Any joint that exceeds the vehicle manufacturer's maximum allowable wear needs to be replaced. The greater the amount of wear, the greater the urgency to replace it. Ball joints are often replaced in complete sets, or at least in matched pairs on both sides (both lowers or both uppers). This is because the joints on both sides of a vehicle usually have the same amount of wear. If one is bad, the other usually is too. Load carrying ball joints usually wear out before ones that don't carry a load, so it may only be necessary to replace the loaded joints instead of the complete set. Replacing a set of ball joints requires separating the control arms from the steering knuckles, a job which can be difficult depending on the design and age of the vehicle. At the very least, it usually requires a special "ball joint fork" tool to loosen the ball joint stud from the knuckle. If this sounds like more of a job than you want to tackle, let a professional do it the work.

Answer: Yes. A clicking sound when turning is one of the classic symptoms of a worn or damaged "constant velocity" (CV) joint. Your car has four such joints on the two front axles: two inboard joints and two outboard joints. The outboard joints are the ones that make a clicking sound when they go bad. Inside the joint are six steel balls, positioned in grooves between an inner race and an outer housing. The balls are held in position by a cage that looks something like a wide bracelet with windows or slots cut in it. When the joint is new, the balls fit tightly into the cage windows. But as the joint accumulates miles, the cage windows become worn and allow the balls to rattle around. The grooves in the inner race and outer housing also wear, which further contributes to noise. When driving straight, a worn CV joint is usually quiet (constant noise would indicate a bad wheel bearing or other problem). But when the wheels are turned to either side, the joint bends causing the balls to click as they slide around in their cage windows and grooves. The noise is usually loudest when backing up with the wheels turned. Repacking the joint with grease won't help because the joint is worn and needs to be replaced. The "normal" life of a CV joint is usually 100,000 miles or more. But a joint can fail prematurely if the rubber boot that surrounds it is damaged or develops a leak.

CV Joint Boots: The boot, which is made of rubber or hard plastic, serves two purposes: it keeps the joint's vital supply of special grease inside, and it keeps dirt and water out. After five or six years of service, it's not unusual for the boot to develop age cracks or splits. Boots can also be damaged by road hazards or a careless tow truck operator who uses J-hooks to tow your vehicle. Once the boot seal is broken, the inside grease quickly leaks out. Starved for lubrication, the CV joint soon fails. Dirt and water can also enter the boot and contaminate any grease that's left inside. Either way, a damaged boot is bad news for the joint. CV joint boots should be inspected periodically (when the oil is changed is a good time) to make sure they are not cracked or torn, and that the clamps are tight. If you see grease on the outside of the boot, it is leaking and needs to be replaced (the sooner the better). If a clamp is loose and the boot is leaking grease at one end, the clamp needs to be replaced.

Original equipment boots are a one-piece design, which means the driveshaft and CV joint have to be removed from the vehicle and disassembled to replace a bad boot. However, there are aftermarket "split-boots" designed for easy do-it-yourself installation. The split-boots eliminate the need to remove and disassemble the joint and driveshaft. You simply cut off the old boot, clean out as much of the old grease as possible from the joint, pack the joint with fresh high temperature CV joint grease (never ordinary chassis grease), then install the new boot. Most split-boots have a seam that is glued together. The seam must not have any grease smeared on it and the glue must be applied carefully for a good seal. Also, the vehicle must not be driven until the glue has cured (about an hour or so). Note: Most professional mechanics do not use split-boots because (1) they don't think a split-boot is as reliable or as long-lived as a one-piece original equipment style boot, and (2) they don't like the idea of installing a new boot on a questionable joint.

By the time a damaged or leaky boot is noticed, the joint has usually lost most of its grease and/or been contaminated by dirt. Unless the joint is removed, disassembled, cleaned and inspected, there's no way to know if it is still in good enough condition to remain in service. If it's making noise, replacing the boot would be a waste of time because the joint is bad and needs to be replaced (most new joints come with a new boot, clamps and grease). But even if the joint isn't making any noise, it may still have wear or internal damage that will soon cause it to fail. Warning: A CV joint failure can cause loss of steering control under certain circumstances. If the joint locks up, it can prevent the wheels from being turned.

Answer: A U-joint (the "U" stands for "Universal"), which is also called a "Cardan" joint after the guy who invented it, is a type of flexible coupling typically used on both ends of the driveshafts in rear-wheel and four-wheel drive vehicles. Each U-joint consists of a four-legged center cross with needle bearing cups on the ends of each leg of the cross. The bearing cups on one pair of legs are mounted to the driveshaft. The other pair of cups are held in place by a pair of U-bolts attached to a yoke that mates to either the transmission or differential. The bearing cups allow the joint to swivel and bend as the driveshaft follows the motions of the differential and axle as the suspension bounces up and down. Most original equipment U-joints on newer vehicles are "sealed" and do not require periodic greasing. But many replacement U-joints as well as the U-joints on older vehicles do have a grease fitting which allows the joint to be lubed periodically.

CV Joints: Aconstant velocity (CV) joint does essentially the same thing as a U-joint, only better. There are two basic types: "ball-and groove" CV joints (called "Rzeppa" joints after the guy who invented them), and "tripod" CV joints. Rzeppa CV joints, which are used as the outer joints on most front-wheel drive cars and minivans, consist of a cup-shaped outer housing, a center race and cage assembly. Machined into the outer housing and center race are six grooves that hold six steel balls. The balls are held in position by windows or slots cut into the cage assembly. The joint is designed so that when it bends, the balls are always positioned at the midway point inside the joint. This eliminates the cyclic variations in speed that a U-joint experiences when it operates at more than a few degrees off-center.

A variation on the Rzeppa CV joint is the "cross-groove" CV joint. It also has six balls between an inner race and outer housing. But this type of joint is designed to move or plunge in and out to compensate for changes in driveshaft length that occur as the suspension moves up and down. This type of joint is used as the inboard CV joint on many European and Japanese front-wheel drive cars.

The tripod style of CV joint consists of a three-legged cross or trunnion with roller bearings on the end of each leg. The trunnion is attached to the driveshaft, and the roller bearings run in machined grooves or channels in an outer "tulip" housing. This type of joint is also designed to plunge in and out, and is used as the inner CV joint on most domestic front-wheel drive vehicles. There are also some Japanese and European front-wheel drive cars that use a tripod-style joint as the outer joint. All CV joints are enclosed by a rubber or hard plastic boot. The boot keeps grease in and contaminants out. CV joints do not require periodic maintenance or greasing, and are engineered to last 100,000 miles or more.

All front-wheel drive cars and minivans have four CV joints: one inner joint and one outer joint on each of the vehicle's two driveshafts (which are also called "halfshafts"). CV joints are also used on the driveshafts of some rear-wheel and four-wheel drive vehicles, too.

Answer: U-joints are not used with front-wheel drive (FWD) because they produce cyclic vibrations when operated at more than a few degrees off-center. A U-joint will cause a change in speed between the driving and driven shafts whenever the joint operates at an angle. As the operating angle of the joint increases, the speed (velocity) of the driven shaft starts to vary during each revolution. And the greater the operating angle, the greater the variation in speed of the driven shaft. The driven shaft still turns at the same number of revolutions per minute as the shaft that's driving it, but because of the geometry of the U-joint the speed of the driven shaft alternately increases (accelerates) and decreases (decelerates) four times every revolution -- which causes the vibrations we're talking about. This isn't a concern in a rear-wheel drive application because the U-joints on the ends of the driveshaft are positioned 180 degrees to one another to cancel out vibrations. What's more, both U-joints always operate at the same angle. But in a front-wheel drive application, the outer joint may have to operate at an angle of up to 45 degrees when the wheels are steered. This is too much of a difference between the inner and outer joints angles for U-joints to handle. So constant velocity (CV) joints are required. Unlike a U-joint, a CV joint always drives the output shaft at the same speed as the input shaft regardless of the operating angle of the joint. Therefore, it doesn't make any difference if the inner and outer joints operate at different angles.

Joint geometry: In a U-joint, the four-point center cross attaches at two points on either yoke. When the joint is bent, two of the arms on the center cross travel in one elliptical path while the other two arms follow a different elliptical path. This is what causes the speed variations that result in vibration. It's hard to visualize, but that's what happens. CV joints handle joint angularity differently. The six balls inside a "Rzeppa" style CV joint are positioned so they always travel in a circular path exactly half way between the joint angle. A circular path keeps velocity constant while an elliptical path causes changes in velocity. So that's the inside scoop on why U-joints won't work in FWD applications.

Answer: There are two reasons why: parts and labor. A CV joint has a lot of metal and precision-machined components so manufacturing and tooling costs are high. Note: You can save some money by going with a rebuilt joint, but it's still going to cost a substantial sum and may not hold up as well as a brand new joint (durability varies greatly depending on the rebuilding procedure used: some joints are overhauled using oversized components to compensate for wear while others are remachined to restore like-new tolerances). Labor (unless you're replacing the joint yourself) is the other factor that adds to the cost of replacement. CV joints are mounted on the ends of the driveshafts located between the transaxle and wheels in a front-wheel drive car. To replace a joint, the driveshaft must be removed from the car. This, in turn, requires removing the wheel, removing a large hub nut that holds the outer end of the driveshaft in the wheel hub, disconnecting the lower ball joint from the steering knuckle so the end of the driveshaft can be pushed back through the hub, and disconnecting the inner end of the driveshaft from the transaxle. With the proper tools and a hoist, a skilled mechanic can usually remove a shaft in an hour or less. But most shops charge according to a "flat rate" system based on "average" labor times published in a manual. These times are established by the vehicle manufacturers and/or the flat rate manual publishers. Most good mechanics can easily beat the flat rate times, and earn themselves a commission on the difference. Unfortunately, you still pay the same as if it took them the full amount of time to complete the job. Hey, nobody said life was fair.

Answer: Time is money in the auto repair business. It's much faster and easier for a mechanic to replace the entire driveshaft assembly with both joints on it than to mess around replacing a CV joint on your old driveshaft. Removing the old CV joint from the shaft, disassembling and inspecting the other CV joint on the shaft to make sure it is still good, reassembling and repacking both joints with grease and installing the boots and clamps is a messy and time-consuming job. So that's why your mechanic is trying to give you the "shaft." He isn't trying to cheat you. He's only trying to save himself some time and effort. The cost of replacement shafts for most FWD cars today has dropped to the point where a complete shaft assembly with new or remanufactured CV joints costs little more (or in some cases no more!) than a brand new replacement joint. That's why most mechanics have gone to swapping shafts instead of replacing individual CV joints. When the shaft is changed, your old shaft and joints are exchanged for the replacement shaft. Your old shaft is then returned to a company that specializes in shaft rebuilding. Your old shaft is then rebuilt using new or remanufactured joints. The shaft then goes back into the parts distribution pipeline and is sold to the next person who needs one. That's how the system works. It's recycling in action, and it actually saves consumers a lot of money. If you're pinching pennies and/or don't plan to keep your car for a long time, you can save some money by asking for a shaft with remanufactured, rather than new, joints. The warranty won't be as good, and the joints may not last as long as brand new ones, but you get what you pay for. Shafts for import vehicles typically cost about 30% more than those for domestic vehicles because there are more different designs of import shafts and joints (some of which can be very difficult and expensive to obtain).

Answer: Whenever you inspect the suspension system, you should test the shock absorbers or MacPherson struts. The test should be performed with the car on the ground, not when the car is being supported on a jack or hoist. The way to test the front and rear shocks or MacPherson strut cartridges is by bouncing each corner of the car. Rock the car at each corner and release. If the car bounces more than 1 1/2 times after you have stopped, take a closer look at the shocks or cartridges. If the car bounces more than it should, raise the car up on a jack. Run your hand over the tire tread completely around the tire and from inside to outside. Cupping or unusual wear in any area indicates the shocks may not be holding the tires on the road. Look for broken mounts, damaged bushings, and oil on the shock absorber barrel. Grab the shock and shake firmly. This may reveal damage to a mount or bushing not apparent at first sight. Substantial fluid on the outside of the shock absorber housing indicates a leaking seal. Fluid cannot be replaced and shocks are ineffective without fluid; shock absorber replacement is required. Shocks should always be installed in pairs, and it is often most economical to replace all four. One indicator of a need to replace the MacPherson strut/shock is oil leakage at the piston rod seal. Also conduct a bounce test. During the bounce test, carefully observe the top strut mount. Any noise or movement here can indicate the need for parts replacement.

Answer: When replacing front or rear shocks, first compare the shocks on the car to the replacement units. The old and new shocks should be the same length and same mounting; carefully observe the position and type of mounting of the original shock absorbers. The shock absorber can be mounted by a thread formed on the end of the piston shaft. This is called a stem mounting. Stem mounting is common on the top end of a shock mounted in the center of a coil spring. The tab stud or cross pin mount is used on the bottom of many coil spring-mounted shock absorbers. Sleeve mounting may be used on one or both ends of the shock absorber; it is used on some front shocks, but is most common on the rear. Before removing any shock absorber hardware, spray penetrating fluid on all the threads. Road splash and rust can make nuts very difficult to remove. Some nuts will probably have to be removed with an air impact wrench and impact socket. To remove front or rear shock absorbers, raise the car on a hoist. Do not allow the front or rear drive axle to hang--make sure it is supported on the hoist. To remove the typical stem and cross pin-mounted front shock absorber, use an open-end wrench to hold the shock absorber stem as shown below. Remove the nut, then remove the upper washer and grommet. Unbolt the cross pin from the lower control arm and pull the shock absorber out through the bottom of the control arm. Make sure the correct number and type of lower rubber grommets and washers are positioned on the stem. Check the instructions with the new shocks and also compare with the old shock mounting. Push the new shock absorber into position through the hole in the bottom control arm. Install the upper washer and grommet, then install the nut. Use an open-end wrench to hold the stem and torque the nut to specifications. Install the bolts that hold the cross pin and torque them to specifications. Rear shocks are often mounted with a stud or cross pin at one end and a sleeve mount at the other end. The stud and cross pin are removed and replaced by the procedure described earlier for front units. The sleeve mount is removed and replaced by removing and replacing the bolt and nut that goes through the sleeve into the mounting bracket. Be sure to torque all the attaching bolts to specifications.

Answer: When you shift gears (with an automatic or manual transmission), you feel a slight pause, then hear a clunk. The can sound like it is coming from the rear or front of the car. The noise may be evident when shifting from reverse to neutral, neutral to forward, or forward to reverse. The problem begins gradually and worsens with use. The probable causes are: 1. Worn CV-joints. 2. Worn U-joints. 3. The differential unit may have too much backlash. 4. The engine's idle speed may be set too high.

Answer: Everything seems fine while you are driving your car except when you go around a corner, and then you hear a clicking noise from one side of the car. Pay attention to when the sound occurs, as it is very helpful when trying to identify what is causing the problem. Normally the problem begins gradually, but the noise may go unnoticed. As the problem gets worse, the noise gets louder. The probable causes are: 1. Loose brake pads. 2. Worn wheel bearings. 3. Worn CV-joints (normally the outer joints). 4. Loose wheel covers, which are sometimes called hub caps. 5. There is a large stone, a nail, or some other hard object caught in a tire.

Answer: Whenever you place the transmission into gear when the engine is warm, you notice a clunk or a jarring motion. Sometimes, the change of gears while on the road feels very harsh and immediate. Normally you hardly notice the transmission changing gears, but now you do. The probable causes are: 1. The transmission fluid level is low. 2. The fluid in your transmission is contaminated. 3. You have an internal problem in the transmission. 4. The idle speed of your engine is too high. 5. You have worn CV- or U-joints. 6. The throttle linkage for the transmission is out of adjustment or damaged.

Answer: You notice a side-to-side wobble in the steering wheel when traveling at steady speeds. The vibration gets worse when you are on an uneven road surface or after going over a pot hole. The probable causes are: 1. Your tires and wheels are out of balance. 2. Your tires don't have the correct pressure. 3. Your tires are worn. 4. A part of the steering linkage is loose or damaged and needs to be replaced. 5. You have worn suspension pieces.

Answer: As you drive down the road and go over a bump, you feel the car continue to bounce up and down well after the bump. Normally this problem will get progressively worse as you continue to drive your car.The probable causes are: 1. Your shock absorbers are worn. 2. The mounts for your shock absorbers are broken. 3. Tyre pressure needs to be checked.

Answer: As you drive the car, you feel a shake through the steering wheel from the tires. A slight wobble means a slight problem. However, a serious wobble indicates a more serious problem. Most of the time this problem starts out as a slight vibration and progresses to a serious wobble. The probable causes are: 1. Tires need balancing. 2. Tires are worn. 3. The wheel is bent or damaged. 4. The wheel lug nuts are loose. 5. There are worn or damaged steering parts.

Answer: You notice that the tires are very worn on the inside or outside edge. The other edge and the center seem to have plenty of tread left. The probable causes are: 1. Wheel-alignment problems, excessive camber. 2. Wheel-alignment problems, incorrect toe.