Diagnosing Noises in Your Car
CV Joints and FWD Axles
This is a very common issue. In fact, on some vehicles, axle replacement is almost a maintenance item. The noises often associated with FWD axles involve the CV joints, or Constant Velocity joints. These joints allow a wide range of motion while still being able to transfer power from the final drive to the wheels.
The noise you often hear with this is a clicking noise when making a tight turn. If you hear this noise, you likely have a bad CV joint. Determining which side is fairly simple. If you make a right turn and hear the noise, it’s the left axle. The opposite is true for the other side.
You can also do a visual inspection. If you see a torn or split outer boot, this is likely the joint that’s making noise. For the repair, replace the joint or the entire axle. These days FWD axles are pretty affordable, and it’s easier than changing a boot or joint. Some FWD vehicles also have a center bearing that is similar to RWD models.
These can also make noise from time to time. As with the RWD models, it’s difficult to nail these down. Just as with the RWD axle, check for movement at this bearing. If you find any, replace it. They really aren’t serviceable.
One note on FWD replacement axles. You might notice that the axle you take out has a rubber damper in the center of the axle, but the new one you’re putting on does not. I can’t really say why this happens, but it does. The rubber is a damper and helps reduce axle vibration during operation. I have yet to see an axle without one cause a vibration. It’s really up to you how you want to handle this. Let’s just say some remanufactured axles are better than others and leave it at that. Here are some videos you might find helpful when dealing with FWD axles.
Suspension Noises
Quite a bit can fall under this topic: shocks, struts, springs, bushings, control arms, torsion bars, drag links, strut rods, and stabilizer links, just to name a few. These components make up your vehicle’s suspension system. Over time, these parts can wear out and end up causing noises. What you would notice as a driver are things like rattles or thumps when going over bumps or rough roads. You might even notice a problem with your vehicle’s handling. If you notice any of these things, it’s worth checking out your suspension for any problems.
Struts, Shocks, and Dampers
No matter what you call them, they all pretty much do the same thing: control the movement of the suspension. Your vehicle is held up by spring tension. If you didn’t have struts, shocks, or dampers when you went over bumps, your vehicle would bounce all over the road. Dampers help prevent this from happening and are designed to keep your tires on the road.
When they go bad, they can not only cause this condition, but they can also make noise. An easy check to see if your dampers are bad is to bounce each corner of the vehicle. It should recover and come back to normal after about three bounces. If it doesn’t, it might be time to take a closer look at the dampers. What you’re looking for is oil leaks. If you see oil leaks on a strut or shock, it’s bad and needs to be replaced.
The dampers use this oil in their operation; when it leaks out, the damper’s ability to do its job is compromised. There are also other parts of the strut that can cause noises. These are the upper strut mounts. Sometimes the strut is still good, but the upper mouth or bearing plate has a problem. If the bearing plate is a problem, you can often hear the noise when you turn the wheel left or right. I usually put my hand on the upper mount while I have a buddy turn the wheel. If I can feel the noise, I suspect the upper strut mounts or bearing plates are the problem. Here are a couple of videos concerning struts you may find useful.
