Tennessee Air brakes practice test
Air brakes is not an endorsement — it is a restriction you avoid. Skip this test, or take your Tennessee skills test in a vehicle without air brakes, and the Driver Services prints an L restriction on your CDL barring you from air-braked vehicles. Nearly every real truck has them.
During the pre-trip static test, after the initial 1-minute settle you apply the brake pedal fully and hold it. For a single vehicle, air loss must be less than:
Air brakes and the L restriction in Tennessee
Two things have to happen before Tennessee will let you drive an air-braked vehicle: you pass the air brakes knowledge test, and you take your skills test in a vehicle that actually has a full air brake system. Do only the first and the restriction still goes on the licence.
That makes the truck you borrow for the Driver Services skills test a licensing decision, not a logistics one. Removing an L later means passing the knowledge test again and retaking the skills test in the right vehicle — cheaper to get it right the first time.
Fees, scheduling and document requirements are set by Tennessee. Confirm the current details with the Driver Services before you go.
What the air brakes test covers
The questions come from the federal CDL manual, so the material is the same in Tennessee as it is anywhere else. The full breakdown — what each section asks and the figures worth memorising — is on the air brakes practice test guide. Everything on this page is the TN half of it.
Before any endorsement there is the written test everyone takes. The Tennessee general knowledge practice test covers it, and the Tennessee DOT physical page covers the medical certificate you cannot be licensed without.
Frequently asked
- Is air brakes an endorsement in Tennessee?
- No, and it works in reverse. Every Tennessee driver is assumed to need air brakes; failing to test on them adds an L restriction to the CDL rather than leaving an endorsement off it.
- How do I remove an L restriction in Tennessee?
- Pass the air brakes knowledge test and retake the skills test in a vehicle with a full air brake system. The Driver Services then reissues the licence without the restriction.