The document discusses different types of braking systems used in vehicles. It describes parking brakes, service brakes, drum brakes, disc brakes, hydraulic braking systems, and anti-lock braking systems (ABS). The key components of braking systems like the master cylinder, calipers, rotors, and pads are explained. Common brake system issues and how to diagnose them are also covered.

1. Brakes

2. Types Parking Brake Service Brake Hydraulic Disc Brakes Drum Brakes Dual System Antilock Brake System (ABS)

3. Play Principles of Braking

4. Brake System Principles Kinetic Energy Mass Weight Speed Inertia and Momentum

5. Coefficient of Friction Video

6. Parking Brake Not an “Emergency” Brake Used specifically to keep a parked vehicle from moving Usually on rear wheels only Mechanically operated Static Friction: at rest friction- More friction Kinetic Friction: in motion friction- less friction

7. Typical Parking Brake

8. Play Parking Break Video

9. Play Parking Brake Adjustment Video

10. Service Brakes Primary Braking System Should be stronger than the engine Hydraulic Operated Can be Vacuum, Hydro or Motor assisted Disc System Drum System Dual System

11. Typical System

12. Hydraulic Principles Fluids cannot be compressed Fluids can transmit Movement Acts “Like a steel rod” in a closed container Master cylinder transmits fluid to wheel cylinder or caliper piston bore. Fluids can transmit and increase force Force Area Pressure

13. Hydraulics Simplified Hydraulic Brake System Drum Brake Master Cylinder Disk Brake

14. Hydraulic pressure is distributed equally in all directions

15. Same line pressure to all wheels

16. The Hydraulic pressure is the same, but the applied force can be changed by the piston size

18. The applied pressure can be raised or lowered by piston size

19. Play Hydraulic Pressure Video

20. Brake Pedal Design Advantage by Leverage First Mechanical Advantage is Driver’s foot Length of Lever determines force applied Uses Fulcrum Pedal Ratio 10 2 5:1 2.5 inches 5 0.5 inch

21. Play Break Pedal Leverage Video

22. System Basics Hydraulic actuation allows multiplication of pedal force. In this system, a 10lb force on the pedal produces 360 lbs of force at the friction surface.

23. Play Break Lines & Hose Video

24. Brake Fluid Properties of Brake Fluid Does not thicken or then with changing heat Must not boil Must be compatible with brake parts material Must lubricate internal parts Must not evaporate easily

25. Brake Fluid types DOT 3 and 4- Polyglycol based Most common Compatible with one another Inexpensive Destroys paint Ruined by moister DOT 5- Silicone Based Used only for heavy duty applications Not Compatible with 4&5 Very Expensive Does not damage paint DOT= Department of Transportation High #= High stands, quality and boiling point

26. Fluid Contaminates Moister- Lowers boiling point water boils @ 212*F DOT 3 boils @ 401*F Petroleum Based Product- soften rubber parts causing swelling Dirt & Debris- causes corrosion and clogs Air and Vapors- Compressible prevents pressure from reaching brakes

27. Play Break Fluid Video

28. Master Cylinder Provides a reservoir for brake fluid and contains the driving pistons in the hydraulic circuit 2 Types Front - Rear split -One piston for front brakes and one for rear -If a leak occurs you could lose front brakes Diagonally split -One piston drives one front wheel and one rear wheel -Diagonal layout allows you to maintain directional control if a leak occurs

29. Play Tandem Master Cylinder Video

30. Play Divide System Video

31. Power Booster in closed position

32. Play Power Booster Video

33. Drum Brakes Expanding shoes create force on the inner surface of the drum Used on the rear of some trucks and SUV’s Self-energizing design requires less activation force Require periodic adjustment

34. Drum Brake System

35. Vented Rotors Vented Rotors have Fins in the spaces between their machined surfaces. These spaces allow air to pass through, which helps carry heat away.

36. Nonvented Rotor Non Vented Rotors are used on smaller vehicles, and have no cooling fins

37. Play Brake Disc Video

38. Disc Brake Caliper Assembly

39. Caliper Types There are 2 types of Calipers Fixed Calipers are disc brakes that use a caliper that is FIXED in position and does not slide. They have pistons on both sides of the disc. There may be 2 or 4 pistons per caliper Floating Much more common Single Piston Easier to work with On “inboard” side of caliper

40. Fixed Caliper Motorcycles and some import trucks and cars use this type Similar to bicycle brakes

41. Sliding Caliper Applies pressure to two pads on opposite sides of rotor Caliper Sliding Fixed Friction Material exposed to air

42. Fixed Caliper Applies two pistons to opposite sides of rotor Caliper stays stationary Disc Brakes require higher hydraulic pressure

43. Play Disc Brake Calipers Video

44. Diagnosis Several different types of Complaints Noise Pulsation Pedal travel More later…

45. Brake Noise Wear Indicator

46. Brake Pulsation Usually a warped Rotor Rotor needs trued on a brake lathe

47. Pedal Travel NO BRAKES!!!! Excessive pedal travel Pedal feels soft and squishy Requires excessive effort to stop vehicle or my cause brakes to not function at all

48. Play Drum Brake Inspection Video

49. Play Disc Brake Inspection Video

50. Anti-Lock Brakes A locked (sliding) wheel offers less braking force than a decelerating rolling wheel The locked wheel also produces little lateral force, preventing steering control Anti-Lock systems (ABS) monitor wheel lock-up and modulate brake pressure to provide controlled braking under most circumstances

51. Play ABS Principles Video

52. Anti-Lock Brakes System can have 2, 3 or 4 channels Trucks typically use 3 channel with only one sensor for the rear axle Most modern cars use 4 channel system Wheel speed sensors monitor each wheel speed ABS controller and high-pressure pump increase or reduce pressure to wheels in order to maintain consistent wheel speeds

53. Play ABS video

54. Play Drum, Disc, & ABS Video

55. Other Braking Systems Air Brakes Exhaust Brakes Electric or Trailer Brake

56. Play Disc Brake Replacement Video

57. Play Replacing The Rotor Video

58. Play Drum Brake Replacement Video