When faced with any noise complaints, take the time to testdrive the car with the customer, if that’s possible. This step not only allows you to confirm the noise you’re chasing, but it also gives you the opportunity to point out any other issues that the customer hasn’t noticed.
You may hear the familiar knocking sound of loose sway bar links or bushings that the customer will be glad to have repaired once you point out it isn’t too expensive of a problem to fix.
But even if the customer isn’t available, it’s important that you testdrive the car before it comes into the bay.
While wheel-bearing noise is pretty easy for most of us to pick out, here are some things we can do to confirm and better pinpoint the problem.
Make note of the sound as the load changes around corners; it will give you an idea of which bearing has failed (the noise will usually increase with load).
If any doubt exists, our final step of the diagnostic process includes running the vehicle on the lift and pinpointing the problem with a stethoscope.
While wheel bearing noise is one of the toughest problems for the customer to describe, it’s not unusual for it to come on so gradually that the customer may not even notice it until you mention it after an unrelated road test. Many times, the customer complaint will send you down the wrong path if you let it. We’ve heard complaints from exhaust leaks, to tire balance, to “it just doesn’t sound right,” that have ended up being bad wheel bearings.
We’ll take a look at the recommended procedure as outlined on the Hyundai service information website, www.hmaservice.com concerning a wheel bearing noise on a 2002 Santa Fe. There’s no reason not to be using this informative, no-cost website for other Hyundai vehicles, as well.
Tackling the Work
While the service information outlines the procedure using a press, the tool manufacturers have certainly stepped up and provided some excellent tools that will make the job easier and more efficient.
In the case of our Santa Fe, it’s a straightforward situation to remove the bearing carrier, making working on a bench a good option.
Be careful with the protective boots on the ball joints and tie rod ends as well as the threads. You also have to be careful with any ABS sensors. If they’re stuck in the housing, it may be a better strategy to leave them in place and unplug them from the harness; and be careful with them as you work on the bench.
I like to tell my guys to think about putting the job back together as they’re taking it apart. It’s easier to clean up the threads on a tie rod end before it’s removed from its taper, than it is later; a couple of extra minutes during disassembly can pay dividends on the other end.
Make sure to look at the hub carrier and knuckle. If the bore is distorted by either a curb strike or on the press, it will cause the outer race to take the shape of the damaged bore. This can cause a bearing to fail prematurely. This can lead to a cycle of comebacks that can cost you a customer.
1. With the bearing carrier or knuckle on the bench, the first step is to remove the hub from the bearing.
2. Pressing the bearing out is the best option. Make sure the knuckle or carrier is properly supported before trying to press out the bearing. Avoid supporting the knuckle on steering arms, strut flanges or brake caliper tabs.
3. Whether you use a press or hub tool to accomplish this step, sometimes you will end up with the outer inner bearing race on the hub.
All the factory information suggests removing that race with a press, but, in practice, we know how difficult it can be to get the puller ears in the space provided, if any is provided at all. You can use a sharp chisel in an attempt to wedge the race over and, more than likely, you’ll be spending some time cleaning up the burrs.
Another method is to use an air chisel against the bearing surface of the race with the hub held firmly in a vice, and drive the race away from the hub allowing for removal. As always, wear proper eye and hand protection, and be aware of any bystanders when chiseling.
4. Removing the bearing from the carrier is not an issue; remove the snap ring, and press or withdraw the old bearing.
Note: You should never have to clean the bore with more than a piece of Scotch Brite pad or sandpaper. Never use power tools. If the bore is enlarged and allows the outer race to rotate in the knuckle, it will cause the premature failure of the bearing.
5. Before you start the reassembly process, inspect and clean the parts. Look at the hub to be sure there isn’t a “step” on the shaft where the bearing rides. And, if you haven’t already done it, clean up the bearing bore in the housing, paying particular attention to the snap ring area where rust tends to build up.
6. When assembling, give your tools a break and apply a light coat of lubricant to the OD of the bearing and the housing before installing the bearing and snap ring if required.
7. Before installing the hub, be sure to install any shields that are behind the hub. We are warned not to press on the outboard inner bearing that doesn’t change the race has to be supported as the hub is installed; this is where the hub tools excel in the adapters provided. We find it easiest to have the hub on the press table and press the bearing carrier onto the hub, making sure the races are fully seated.
8. Reinstalling the knuckle will create no problems but, as the final step in the bearing replacement job, torque the axle nut to the recommended level. The torque specs for different makes and models vary. The rating is dependent on the size of the bearing, pre-load and the diameter of the axle shaft. When you are tightening the nut, you are stretching the axle shaft like on head bolts on an engine.
Make sure to look up the torque spec and the procedure. Some late-model vehicles are not only using a torque spec, but a torque angle specificatio.