2024 CO CDL Practice Test: Class A - Test 4 Based on 2024 CO CDL Handbook 23. Which of the following is not a reason for hydraulic brake failure? A Brake fade on long hills B Loss of hydraulic pressure C Downshifting Next More 23/29 Progress 0 Errors Restart Next Next Class A - Test 4 Back to Test List Class A - Test 3 Class A - Test 5 Challenge Library 12 More CO CDL Practice Tests 5 Class A - Test 5 6 Class A - Test 6 7 Class A - Test 7 8 Class A - Test 8 9 Class B - Test 10 Class B - Test 2 11 Class B - Test 3 12 Class B - Test 4 13 Class B - Test 5 14 Class B - Test 6