Air disc brakes are becoming increasingly popular in the trucking industry due to their superior performance and reduced maintenance requirements. However, adjusting or changing the air disc brakes on a semi-truck can be intimidating for those unfamiliar with the process. In this blog post, we will guide you through the steps to safely and effectively adjust or change air disc brakes on a semi-truck.
Prepare Your Tools and Equipment
Before starting the process, make sure you have all the necessary tools and equipment. You will need a torque wrench, a lug wrench, a jack stand, a hammer, a brake adjuster tool, and replacement brake pads if you are changing the brakes. Additionally, make sure you have a clean and flat surface to work on, and wear the appropriate safety gear such as gloves and eye protection. The most common Air Disc Brake Setup is by Bendix and you can find the brake manual by following this link!
Safety
All too often people hurt themselves doing brake jobs by not paying attention to detail. You may be in a bit of a rush but you need to make sure you do a pre inspection on your jack stands and yes I do mean use Jack Stands do not just use a jack that is the fastest way to hurt yourself.
Removing Wheels and Tires
This is simple make sure you keep all the lug nuts and studs with the wheel end it came off of.
Inspect the Brake Components
Before you tear it apart take a quick picture. This will help you if you cant figure out how something was oriented or forgot where it went. Also be sure to inspect the caliper boots for any tears. You can find the inspect disc out of service specifications in the attachment in the first paragraph. Also do not adjust the pistons out that far to inspect the boot because they can fall out of the caliper and you will have to rebuild the whole caliper to get them back in!
Cleaning and Reassembly
- Don’t go all crazy with the brake clean!
- Don’t put the pads in backwards! They will slide right in backwards!
Adjust the Brake Pads
To adjust the brake pads, use the brake adjuster tool to turn the adjuster bolt until the pads are snug against the rotor. Then back it off about 3 clicks or until there is no drag. Make sure you do not over-tighten the adjuster bolt as this can cause the brakes to drag and overheat. Once the brake pads are adjusted, reassemble the wheel and tire assembly.
Torque the Wheel Nuts
USE A TORQUE WRENCH! USE A TORQUE WRENCH LOL. That is not a 1 inch impact! Come on now lets be professionals.
Test the Brakes
Be sure to get the brakes hot on the test to help the pads start to break in. Yes brake pads have a break in period how long that is depends on the driving habits!
If you need more help watch this video of me doing it on a mock up.
Peace!
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