Brake Drum Problems, Bad Brake Drums

Many vehicles today still come equipped with a drum braking system on their rear wheels. Although disc brakes perform better, especially in wet conditions, drum brakes are more cost effective than disc brakes and as a result are still used on the rear axles for some makes and models. If you do have drum brakes on your vehicle, learning rear brake drum problems and how to diagnose them could potentially save you money on your car repairs.

There are a few signs that you should look for in order to determine if your brake drums need servicing. If your braking does not feel right when you press on the brake pedal there may be a problem with the drum brake system. When braking, you should expect firm resistance from the pedal as an indication that the braking system is functioning properly. Rear Brake Drum noise is also a sign that you will want to inspect your drum braking system. Finally, if you are braking and you experience a shuddering feeling, or you do not brake as quickly you should you will want to determine what is causing this problem by removing the brake drum

When you have the brake drum removed, you will be looking for a number of imperfections that can be causing brake drum problems. First, look for any signs of visible cracks, hairline cracks, deep scores and grooves, discoloration, or grease stains. This is the most obvious problem to spot and you will need to replace the drums for the more serious imperfections.

Next, measure the thickness of the brake drum linings (brake shoes). Your brake drum linings should not have a thickness that is less than 1/8 of an inch. If it is less than this, it could be causing noise when you brake. It is best to change the linings if you suspect they are too worn, as ignoring them can cause deep grooves in your brake drum that result in it needing to be replaced sooner. If you are changing the brake linings it is best to replace all of them, as failure to do so can cause your vehicle to lurch to one side.

A brake drum that is out of shape could be causing shuddering or pulsation when you are braking. The drum will warp into an oval shape and doesn’t allow for optimal clearance between the drum and shoes. If this has happened to your brake drums you will need to replace them.

Other signs that you should be looking for brake drum problems are excess rust, corrosion or oil on the brake drum, shoes or surrounding brake parts (master cylinder, hoses, lines, springs). If you are experiencing any of these brake drum problems you will want to have your drum brakes serviced. Failure to do so can cause failure of related brake parts and will significantly decrease your safety on the road. 

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