Jim Grant's Tech Tips '99 Mitsubishi Galant ES, Buzzing Front End Q: My wife and I are starting to notice a buzzing sound coming from the front-end of our'99 Mitsubishi Galant ES. We were told it could be the wheel bearings. While in motion we hear it, and as we slow down to a stop, it diminishes. Also, while slowing down we feel it vibrating through the gas pedal. - M. Boyd Sr A: It seems somewhat odd that you're feeling the buzz/vibration through the gas pedal. Unless, the buzz/vibration is transmitting through the floor to the mount for the gas pedal pivot. You could have a tire problem. If rotating the tires moves the noise then you know what has to be done. Wheel bearings on the other hand can be a bit of a challenge to pin down. A wheel bearing in the early stages of failure will often elude detection when checking for looseness or roughness. It takes the weight of the vehicle to get that bad spot in the bearing talking loud enough. When diagnosing the early phase of a wheel bearing failure we tend to use the Drunken Driver Technique (DDT). Using the DDT approach has to be done in an area that the highway is smooth, there is no traffic and most definitely no police. The vehicle needs to be brought up to a safe speed that the buzz/vibration is easily noted. Then while holding that speed turn the steering enough to mimic a driver that is under the influence. Now I don't mean getting the vehicle side-wards in both lanes. A gentle sway from left to right; will cause the load on the wheel bearings to change, it doesn't take much. If this motion causes a change then it is likely that there is a wheel bearing that is starting to fail. Be aware that this diagnostic approach will cause concern if seen by law enforcement and may result in detainment. The, "I'm just checking my wheel bearings officer" line probably won't work.
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