This month, we’re going to take a look at undercar service on the Kia line of cars and SUVs. Kia has made a good name for itself in the market by offering affordable and dependable vehicles that deliver a good value to the customer. Customers tend to keep these cars for many miles, and they will provide plenty of opportunities for repairs, so there is no reason your shop should not have its fair share.
I think we’ve all become aware of the importance of preventive maintenance, not only for our shop’s benefit but for our customers, as well. While there are some problems that will motivate the customer into your shop, an equal amount will be discovered as the car is serviced. Always encourage your customers to keep their vehicle maintenance up to date, and never assume that the customer knows all the services you offer, or how you can accommodate their vehicle repair needs.
While the Kia suspension system will provide many problem-free miles, it’s important that you not take it for granted. From a safety standpoint, it could be argued that the steering and suspension system on any car is the most critical. That’s why it’s so important that every car that goes on the lift gets a basic safety check. You also have the satisfaction of knowing you solved a potential problem and put the customer in a safer car.
With the MacPherson strut setup being the system of choice on Kia’s line of cars, a simple shake, rock and roll will pick up problems that may go unnoticed by the driver. Grab the wheel at the 9 and 3 o’clock positions and shake it from side-to-side, feeling for looseness in the steering system.
If you feel some play, have an assistant look for the movement, concentrating on the inner and outer tie rod ends, side movement of the ball joint, control arm bushings and wheel bearing play. Move your hands to the 12 and 6 o’clock positions and continue rocking the wheel. Here you’ll pick up play in the strut shaft or mounting, ball joint and control arm bushing. If there was any wheel bearing play in the shake test, it will also be noticeable.
Finally, spin the wheel to check for noises and free rotation. Any dragging is probably a result of a brake problem and should be investigated.
If you find play at the inner tie rod, confirm that it’s the joint, and not the rack bushings, that are worn. If the rack boot allows it, squeeze the boot to feel that the joint is the problem and the rack isn’t loose and moving in the housing.
This will also give you an indication if the rack boot needs to be replaced. It’s always a good practice to replace the boot, but you may find it’s easier to obtain a tie rod end rather than a direct-fit boot. Some of the universals fit well, but if you have to order the tie rod end, add the boot kit to the order.
With outer joints, it’s a good practice to make note of the length of the rod before the end is removed to get the toe in the ballpark on reassembly. Many techs simply count the turns when the rod is removed, but a measurement from the center of the joint to a known point is a good backup. Either way, be sure the toe is within specs before the car is returned to the customer. If the play is a result of a worn ball joint, most Kia models will require that you change the lower control arm, as the joints are not replaceable.
The most common suspension complaint you’ll hear from the car owner will be noise related. It’s often described as a creaking or rubbing sound, as well as the familiar knocking complaint. While a road test on a road in poor condition will confirm the complaint, we have better luck with rocking the car side-to-side while checking for looseness that will lead to the knocking sound. Most of these noises will be traced to the anti-sway bar mounting and links. Rocking the car will unload and load these components, usually resulting in a diagnosis you can be confident with.
The rubbing and creaking noises can be a bit more challenging, mostly resulting from the vagueness of the complaint. In this case, a road test is essential to confirm the complaint and diagnosis the problem. We should all be familiar with picking up a wheel-bearing problem by changing the load and looking for the noise to change with the load. A creaking or bed-spring noise will again have us rocking or, in this case, just pushing on the car in an attempt to duplicate the noise.
There are a couple of listening devices to aid in this procedure, but we generally rely on a simple mechanic’s stethoscope and feeling for vibration in the suspect joint. If you suspect the creaking noise is coming from a bushing, look closely for signs of movement at the attaching point; rust in that area is a strong indication of movement. If you suspect there is movement, be sure to loosen and then tighten the suspect hardware. Of course, this should be done with the vehicle sitting on the wheels to avoid loading the bushing.
If play in the wheel bearing is noticed, it should be taken care of whether or not it’s quiet. Check the torque on the axle nut; if it’s loose, you’ll have to make a judgment call. Is it the result of a previous repair, or is the bearing or hub worn? If the play is excessive and the re-torque has no effect, it would pay to be sure a hub is available before the car is disabled on the lift. While it’s not a common problem on Kias, it’s not unheard of for the hub to show wear on the inner race area, especially in light of the amount of trouble-free miles these cars deliver.
Another thing to keep in mind is what is obvious to us is not so obvious to our customers. Many times, we’ll get complaints of noises that turn out to be brakes that are metal-to-metal or a CV joint coming apart. Many times, these things can be determined at the vehicle write up, but it always pays for the tech to take a quick ride in the car before it’s on the lift so you really know what you’re looking for. You may very well pick up something that the customer hasn’t noticed. Remember that when you point out what the customer needs to restore his/her vehicle to the proper condition, it’s another step in providing top-quality service.
No discussion on undercar service would be complete without talking about brake service. While not as simple as the suspension, Kias will provide little challenge for any tech currently handling brake work. All it takes is paying attention to detail and good work habits — nothing new there.
The first step in any brake job is to establish why the customer thinks the brakes need to be serviced. The most common complaint we’ll hear is a heavy metal-to-metal grinding sound when braking, indicating that one or more of the pads are worn to the backing plate. But it’s the more obscure problems that require some specific questions. For me, the most important question is, “Will the tech experience the problem on a road-test?” If the answer isn’t “yes,” get as much detail as you can about when the problem occurs.
An occasional long pedal could be a master cylinder bleeding down, which usually happens in a stop-and-go or a downhill situation where the brakes are being used. Or, it could also be the fluid heating after a run on the interstate, making the pedal fade as a result of the brakes binding. Knowing when the problem happens will not only save you some time, but it will certainly help you avoid a misdiagnosis.
If you’re looking at a grinding problem, the next step is to look for uneven wear. If one wheel is showing more wear than the other on that axle, it’s time to do some investigating. The most likely scenario is a caliper or hardware issue that caused unexpected wear, and the key to a successful job is knowing which is the culprit.
Now before you jump to the conclusion that you have a frozen caliper, take a couple of minutes to confirm the diagnosis and look at the rest of the system so you can give the customer an accurate estimate, and get all the parts you need in one call. The nuts and bolts of brake replacement are familiar to us all, but it never hurts to review the basics.
The first step is to confirm what is causing the brake to drag. While your first thought might be the caliper, you have to keep in mind that there was no customer-reported odor or vibration after an extended interstate run that you would expect with a locked-up caliper. And, you know the rotor will be showing signs of overheating, as a result of that wheel dragging, or being asked to do more than its share of the work.
The first step is to push the caliper pistons back, but, before you do, attach your bleed bottle and open the bleeders so you’re not pushing the most contaminated fluid back up through the dirt-sensitive ABS unit.
You’re going to be bleeding and flushing the system anyway as part of the service, so you might as well get rid of that used up fluid from the calipers right away.
With the bleeders open, the pistons should return with little effort; if not, consider a pair of replacement calipers. If the problem doesn’t appear to be the calipers, check for the pads sticking in the caliper brackets, and don’t overlook the slider pins as a source of binding. It’s important to keep in mind how critical smooth mechanical operation is to the braking system.
Remember that we have more than 1,000 psi applying the brakes, and we’re relying only on caliper piston seals and mechanical operation to release them.
Don’t forget about mechanical operation when faced with some of the other common complaints you hear with brakes. Everything from a long pedal stroke, to a good pedal that just doesn’t stop well, can be traced back to the same mechanical issues we’re looking at while diagnosing the uneven wear.
With the calipers off the brackets, continue to look for issues that could be causing our uneven wear problem. If the caliper pistons moved freely and the boots are in good shape, turn your attention to the sliders and pad movement. If you find nothing dragging on the worn side, double-check the other wheels for binding that’s preventing that caliper from doing its fair share of the work. Usually pad wear patterns will indicate this kind of problem.
You can and should prevent these problems by using good work habits when we’re performing any brake service. When you’re replacing friction material, take the time to clean and protect the surfaces of the caliper bracket where the pads contact. Be sure to remove the anti-rattle hardware to get rid of any rust that may have built up under these parts. Remove, clean and lubricate the sliders, ensuring a good, solid brake pedal, as well as an ABS system that will function as designed.
Any car that went metal-to-metal would be getting rotors because of the scoring, but Kias, like so many late-model cars, tend to need rotor replacement. It’s very common to have a solid buildup of rust and corrosion on the non-friction area of the rotor, and for the low cost involved to replace it, it just doesn’t make sense to risk a noise or vibration comeback.
Kia rotors are not captured behind the hubs, making replacement simple. But, like everything else we’ve talked about, take the time to clean up the hub so you’re not risking knocking that new rotor out of true.
HYDRAULICS AND ABS
One thing we haven’t talked about is a hydraulic problem that could lead to excessive wear. While certainly not a common problem on Kias, it’s possible that you could encounter a situation where there is pressure in the line when the pedal isn’t depressed. This could be caused by too little clearance in the master cylinder push rod, but this problem usually shows up only after the vehicle is driven and the brake fluid heats up.
Or, you could have a brake hose with an internal failure that is acting like a one-way valve holding pressure at the caliper. Any of these problems are easy to diagnose if they can be duplicated; opening the bleeder valve will release any pressure in the caliper. To confirm the hydraulic system is the problem and to help pinpoint where the problem is, firmly apply the brakes and release them to put pressure in the system and work backward from the caliper, loosening connections to find the restriction.
I’m sure you’re going to inspect the rear brakes before the estimate is written. Again, be sure everything is operating freely. Many Kias are equipped with rear drum brakes; don’t overlook the rear wheel cylinders for smooth operation that’s critical, just like on the front. If the shoes are good, there’s no reason to disassemble, but push on the pistons to be sure the cylinders aren’t frozen. If the shoes are worn, don’t forget those good work habits and be sure to free up and lube the contact areas of the backing plate, as well as all the adjustment and handbrake hardware.
We’ve talked about the mechanical aspects of the undercar service, but Kia certainly hasn’t been standing still when it comes to the electronic aspect of undercar improvements. ABS has been in use for years, while later model vehicles are equipped with Electronic Stability Control (ESC).
This system looks at wheel speeds, brake and steering inputs as well as vehicle yaw and lateral acceleration to assist the driver. We don’t have time to cover these systems in this article, but it’s important that your shop makes the investment necessary to be able to diagnose these systems. It will require a scanner that has the enhanced capabilities required to access these systems. While the factory tools would be ideal, there are other options available that will give you access to a variety of vehicles.
With these tools becoming more affordable, there is just no reason for your shop not to have one. If you’re looking for more information on these systems, just point your browser to Kia’s technical info website at www.kiatechinfo.com. There is no charge to register and you’ll find a wealth of information on the site. Kia wants us to be able to repair their cars; there’s no reason we shouldn’t take advantage of that.
Access to good, quality information to service Kias with greater precision is good news for you and your customers.