2024 OK CDL Practice Test: Class A - Test 6
Based on
2024 OK CDL Handbook
3. In tractors and straight trucks spring brakes will come on fully when the air pressure drops to what range?
A
10 to 20 psi.
B
10 to 30 psi.
C
20 to 45 psi.
D
50 to 80 psi.