Taming Mr. Toad’s Wild Ride Complaints
Some ride complaints are straightforward and easy to explain: it pulls to the right, or there’s a vibration at 60 miles per hour. Other ride complaints may be the most exasperating things for a customer to explain to the technician or service writer. Wander, looseness and instability are all terms that we as technicians can understand. However, these same conditions can be very difficult for some people to accurately explain to us. To make matters worse, these symptoms often happen only at a particular road speed or under certain conditions.
You may find that many customers ask for an alignment when what they really need is tire/wheel balancing to resolve their ride complaint. Communication is the main key to customer satisfaction. Having a customer drop a car off and tell you that there is a ride problem without elaborating on the details is a prescription for disaster. Getting all the information you need can help you to perform a proper evaluation of the complaint – and prevent your customers from feeling like Mr. Toad on the ride of his life.
A check sheet can come in handy when it comes to acquiring information. You can create your own ride complaint checklist based on the common questions you already probably ask: Does the vehicle pull or drift, and if so, which way? Is there abnormal tire wear? Is there any vibration?
Are there any unusual noises, and if so, when do you hear them? Where does the noise seem to be coming from? Is there any looseness? Is the steering wheel centered? Has there been a collision or previous repair? Does the problem occur while driving straight or in turns? Which way?
Some customers may tow a trailer or otherwise overload their vehicle. Does the problem occur only during these conditions? Once you’ve gathered all of the pertinent information, a test drive is in order before any repairs or inspections are made. It’s imperative to confirm the existence of the problem before we attempt to fix anything. How else will we know if we’ve fixed the problem? If the symptoms are intermittent, it’s best to have the customer go along for the test drive, or have him drive with you in the car. This serves two purposes. The first is that if there are multiple symptoms, the customer can identify which ones he is concerned about.
I’ve had customers complain of a rattling noise and upon test driving the car, found at least four distinct noises. Without the customer present, it can be very difficult to identify exactly which noise the customer wants exorcised.
The second reason is that if the problem does not occur during the test drive, you won’t have to deal with a situation in which a customer thinks you missed the problem or simply slough it off as not being important. It’s annoying to a customer to get a call from you saying the car’s not acting up.
Often they will think that you’re missing it, when in reality you’re not. By having the customer with you on the test ride, if the symptom truly can’t be reproduced, the customer won’t doubt your sincerity about fixing the problem.
Ride problems can sometimes be elusive. Factors that can come into play are road speed, engine speed, road surface or crown, cornering, temperature and humidity – things that might not always be simulated in a test drive.
After the test drive, a visual inspection is the next order of business. Of course, you need to inspect for the usual: tire pressure, ride height and suspension components for wear.
Today’s low profile tires can cause a pull with as little as 4 psi difference from side to side. Tires of the same size, but produced by different manufactures, may cause a pull due to rolling resistance or diameter differences. Tire and wheel damage due to hard curbing or chuckholes may be the cause.
You can’t align sagging springs, damaged tires and wheels, sloppy ball joints or worn bushings. If you have a pull, it’s a good idea to swap the front tires left to right to see if the tires are causing the pull. If, after swapping the tires, the pull is to the same side, the tires are not at fault.
Steering pull can also be caused by incorrect wheel alignment. A vehicle will pull to the side that has the most camber and/or the least caster.
Brake pull is an area that can be easily misdiagnosed as a ride control problem. A stuck caliper is the most obvious source of this malady. And in most cases, the obvious source will need replacement. But sometimes a caliper is replaced and the problem still persists. Remember that a stuck caliper can cause a pull even when the brakes aren’t applied. An often misdiagnosed cause of pull is a collapsed brake hose. The hose will look OK on the outside, but the inner liner will cause a restriction on the inside. A brake hose problem like this can take two forms: 1) it can act like a restriction in the line; and 2) it can act like a check valve.
In the first case, the car will pull to the side with the good brake hose upon immediate application of the brakes, but after a second or two, the pull goes away. Because the caliper needs a relatively large volume of fluid to move the piston, the side with the collapsed hose will apply later than the one with the good hose. This is why the pull can be extreme on the initial pedal application, but dissipates as the fluid slowly moves the piston. The customer may not relate the problem as a pull because the vehicle may simply feel unstable, as it initially veers to one side and then stops straight.
In the “check valve” situation, fluid will freely flow into the caliper, but will not return to the master cylinder. This can mimic a stuck piston. Check this further by loosening the bleed screw while turning the wheel by hand. If the wheel turns freely after relieving the pressure in the caliper, the caliper is OK. If only one wheel is affected, it’s probably the brake hose.
To be sure it’s not something upstream, reapply the brakes and release. Then loosen the hose at the fitting on the body (not at the caliper). If the problem goes away now, the hose is OK. Look at the proportioning valve, master cylinder or ABS system.
Brake pulls from the rear can be differentiated from front pulls by their characteristics. A pull caused by the front brakes is usually severe and tugs on the steering wheel. Rear brake pulls have little impact on the steering wheel but cause the car to drift into the next lane and make the car feel unstable.
Hard steering (difficulty turning the steering wheel) caused by worn or seized parts is easily masked by power steering-equipped vehicles. A quick test is to turn the steering wheel lock to lock, with the front wheels off the ground and the engine turned off, while feeling for binding. Disconnecting both outer tie rod ends will allow you to ascertain if the binding is on the left side, right side or steering rack.
Power steering system problems can cause also hard steering. Low fluid levels, a worn pump, or worn steering rack or box should be investigated. Some vehicles are equipped with variable assist power steering.
These systems can be vacuum operated (engine load) or electronic. Electronic systems are obviously more accurate, but the goal is the same: to increase assist during low speeds and parking while providing good road feel at higher speeds. Insufficient assist at the wrong time will generate a hard steering complaint from the driver.
A hard or harsh ride can often be caused by overinflated tires. Drivers inflating tires without a good air pressure gauge can really go wild with inflation pressures.
Also check to see if the tires are the OE size, or are different than OE. Dropping from a 70 series to a 60 or 50 series tire significantly reduces sidewall height, thereby reducing the ability of the tire to smoothly absorb impacts. Any significant tire size change also means a different inflation pressure – make sure the recommended pressure is used.
Worn struts, shocks or springs can cause a harsh ride, particularly upper strut mounting plates, bushings and extremely worn ball joints.
Vehicles equipped with electronically adjustable suspensions could deliver a ride that’s too harsh or too soft due to problems with the electronic struts or shocks, the ride control computer or one of the various sensors feeding information to the computer.
Simple systems have two or three settings for “soft,” “normal” or “firm” operation. More sophisticated systems will adjust shock and strut firmness automatically, based on vehicle speed, steering wheel position, braking, acceleration and other parameters. You’ll need vehicle-specific repair and diagnostic information to service these vehicles.
Don’t overlook the possibility that worn upper strut mounts are causing a memory steer condition. This is a condition where excessive friction in the steering or suspension system causes the steering to not want to return to center.
Typically, caster will cause the steering wheel to self-center after a turn. If there is too much resistance to the centering force that caster provides, the steering may not fully return to center. Worn strut mounts can cause this friction.
If they are severely worn, the suspension spring can actually “wind up.” If this happens, the steering may want to return to the side that you last steered it, even if you manually bring the steering wheel back to center. Hence, the name “memory steer.” Tightening a rubber-filled tie rod end with the steering gear not centered can also cause a memory steer as the rubber tries to return to its most relaxed position.
Wandering or play in the steering is usually due to worn or loose parts. A bouncy, wallowing ride due to worn shocks or struts is not only nauseating, it can cause loss of steering control in a panic situation and even increase braking distance. While worn tie rods and idler arms are common sources of excessive steering play, don’t overlook control arm bushings, rack mounts, steering couplings or a worn steering box. Check for worn or misadjusted wheel bearings or loose wheel lug nuts.
A car that feels unstable while driving, but has no excessive free play in the steering, may have rear suspension problems. An independent rear suspension has a lot more components to wear out than the good old live axle. Alignment angles that are extremely out of spec can also cause instability, especially if the wheels are toed out.
One of the most difficult ride complaint problems to solve is noise. And it doesn’t go away just by turning up the stereo. Often, only certain conditions, such as a particular kind of bump, will cause the noise. Rubbery noises created by turning the steering wheel while sitting still are often caused by worn strut mounting plates (spring retainers).
Rubbery, squawking noises heard over large, slow undulations, such as a dip in the road, can be traced to sway bar bushings. Beware, bushing noises can be temperature and/or humidity related.
A hard metallic sound heard on sharp bumps at low speed is usually caused by a part that is worn out but doesn’t cause much steering play. Prime candidates are ball joints, control arm bushings and shafts, and mounting fasteners. Yes, don’t forget loose bolts. If you have a combination of symptoms, suspect those parts that can cause both problems. Loose steering, along with a knocking sound, could easily be caused by a worn steering coupling between the steering column and the steering box or rack.
Sometimes the noise can be duplicated in the shop by bouncing the car. Remember that the tires will not allow the same type of suspension movement when the car is static. Resting the car on slip plates will allow a less restricted movement, sometimes uncovering an otherwise latent noise.
Wheel bearing noise typically starts at around 25 mph and gradually gets worse with speed. Beware that on front-wheel-drive vehicles, the old trick of making a quick lane change, left and then right, to shift the load on the wheel bearings to see if the noise changes, may lead you to an incorrect diagnosis. Unless the bearings are really shot, don’t expect the noise to change much.
CV joint noises are most obvious with high steering angles in conjunction with high torque, such as starting from a dead stop with the steering wheel turned.
Vibrations, too, can be difficult to diagnose. Oftentimes customers will request an alignment when they really have a tire/wheel balance problem. Remember to ask the right questions up front so that you aren’t stung by this common situation.
While tire/wheel imbalance will account for the vast majority of vibration complaints, other systems may occasionally come into play. Worn motor mounts or other driveline-related components that are incorrectly routed or supported could cause difficult-to-diagnose noises and vibrations.
Vibrations can sometimes be reproduced in the shop with the vehicle on a frame contact lift. To help determine from which area of the vehicle the vibration is emanating, have a helper bring the vehicle to the same conditions that cause the problem during the test drive (road speed, engine speed, gear selection, etc.) Be careful around rotating wheels and shafts.
Remember, tire/wheel vibration is always at a frequency much lower than the vibration produced by bad universal joints in a RWD car. Don’t overlook a bent or out-of-balance drive shaft. It happens.
Who Is Mr. Toad?
J. Thaddeus Toad, the lead character in “Mr. Toad’s Wild Ride,” one of the first attractions that opened at Disneyland in California in 1955, is from the classic book “The Wind in the Willows” which also became a Disney animated film. In the story, Mr. Toad, who today would have been considered a bit of a gearhead, is obsessed with motor cars. He eventually steals an automobile with some of his friends and goes on one helluva ride. (Toads don’t make for great drivers.) The attraction sent riders racing through several black-lit scenes in a turn-of-the century jalopy, making it cult classic among the Gen-Xers. A “Mr. Toad’s Wild Ride” attraction was also part of Walt Disney World when it opened in Florida in 1971. However, in 1998 the attraction was closed and the space was used to create a new Fantasyland attraction.