How to fix an air leak on a semi truck? / How do I find an air leak in my truck?

Regardless what make and model of semi truck you have (as long as it has air brakes), this is a general test procedure for a DIY air leak inspection.

Check for air leaks with these 3 procedures:

• Remember these procedures need to be done when the truck has more than 100 PSI, but best if they are done right after the truck purges, notifying you its at maximum pressure, also soap and water in a spray bottle make identifying a lot easier

1. Parking brake (yellow tractor air supply knob) set / pulled out, walk around the truck or trailer and listen for a *hissing* noise

2. Parking brake (yellow tractor air supply knob) set / pushed in (MAKE SURE YOU CHOCK THE WHEELS TO PREVENT THE TRUCK FROM ROLLING), walk around the truck or trailer and listen for a *hissing* noise

3. Parking brake (yellow tractor air supply knob) set / pushed in AND the brake pedal firmly pressed (this will require 2 people), walk around the truck or trailer and listen for a *hissing* noise.