Complete brake fluid flush to replace old brake fluid with fresh DOT 4 LV fluid, removing moisture and contaminants from the entire hydraulic brake system.

Warnings

Tools required

Parts

• Motorcraft DOT 4 LV Brake Fluid × 2 — PM-20 or equivalent DOT 4 LV

Fluids

• Motorcraft DOT 4 LV Brake Fluid — 0.5 qt

Preparation

1. Park vehicle on level surface, place transmission in Park, engage parking brake firmly
2. Place wheel chocks behind rear wheels
3. Remove master cylinder reservoir cap and inspect fluid level and condition (dark fluid indicates need for flush)
4. Using turkey baster or fluid pump, remove as much old fluid as possible from master cylinder reservoir without allowing it to run empty
5. Refill reservoir with fresh Motorcraft DOT 4 LV brake fluid to MAX line
6. Loosen all four wheel lug nuts 1/4 turn while vehicle is on ground
7. Raise vehicle with floor jack and support securely on jack stands at all four corners
8. Remove all four wheels completely
9. Locate brake bleeder screws on all four calipers (rear of caliper body)

Procedure

1. 1

   Prepare bleeding sequence
   Bleeding sequence for 4WD F-150 is: 1) Right Rear, 2) Left Rear, 3) Right Front, 4) Left Front. This ensures proper brake system air purging starting from farthest point from master cylinder. Verify reservoir is filled to MAX line before beginning.
2. 2

   Bleed right rear caliper
   Attach clear vinyl hose to right rear bleeder screw and place other end in catch bottle. Have assistant pump brake pedal 5-6 times and hold firm pressure. While pressure is held, use 8mm wrench to open bleeder screw 1/4 to 1/2 turn. Fluid will flow into hose. Close bleeder screw BEFORE assistant releases pedal. Repeat until fluid runs clear without bubbles. Check and refill master cylinder reservoir after every 4-5 pumps.
   ⚠Always close bleeder screw BEFORE releasing brake pedal, or air will be drawn back into system.
   Torque spec

   Bleeder Screw10 Nm (7 lb-ft)
3. 3

   Bleed left rear caliper
   Move to left rear caliper and repeat bleeding procedure. Attach hose to bleeder screw, have assistant pump and hold brake pedal, open bleeder 1/4 to 1/2 turn, observe fluid flow, close bleeder before pedal release. Continue until fluid is clean and clear. Monitor reservoir level constantly.
   Torque spec

   Bleeder Screw10 Nm (7 lb-ft)
4. 4

   Bleed right front caliper
   Move to right front caliper and repeat bleeding procedure. Front calipers typically require more cycles to achieve clean fluid due to larger caliper volume. Continue bleeding until no air bubbles appear and fluid color matches fresh fluid from bottle. Refill reservoir as needed.
   Torque spec

   Bleeder Screw10 Nm (7 lb-ft)
5. 5

   Bleed left front caliper
   Complete bleeding sequence at left front caliper using same procedure. This is the final bleeder point. Continue until fluid is completely clear and bubble-free. After closing final bleeder screw, have assistant pump brake pedal several times to verify firm pedal feel.
   Torque spec

   Bleeder Screw10 Nm (7 lb-ft)
6. 6

   Verify all bleeder screws sealed
   Inspect all four bleeder screws to ensure they are properly tightened to 10 Nm (7 lb-ft). Do not overtighten as bleeder screws are brass and will strip easily. Wipe away any spilled brake fluid from caliper and suspension components with clean rag.
   ⚠Bleeder screws are soft brass and easily damaged. Use proper 8mm wrench and do not exceed 10 Nm torque specification.
   Torque spec

   Bleeder Screw10 Nm (7 lb-ft)
7. 7

   Final reservoir fill and cap installation
   Fill master cylinder reservoir to MAX line with fresh Motorcraft DOT 4 LV brake fluid. Ensure reservoir cap gasket is clean and in good condition. Install cap securely. Wipe any spilled fluid from master cylinder and surrounding painted surfaces immediately.
8. 8

   Reinstall wheels
   Install all four wheels onto hubs, ensuring they seat properly. Thread lug nuts by hand initially to prevent cross-threading. Snug lug nuts in star pattern with wrench but do not fully torque while vehicle is on jack stands.
9. 9

   Lower vehicle and torque wheels
   Carefully lower vehicle from jack stands to ground. Remove jack stands and lower jack completely. Torque all wheel lug nuts to 140 Nm (103 lb-ft) in star pattern to ensure even wheel seating.
   Torque spec

   Wheel Lug Nuts140 Nm (103 lb-ft)

Reassembly

1. Double-check that all bleeder screws are tightened to specification and not leaking
2. Verify master cylinder reservoir is at MAX line and cap is secured
3. Inspect ground beneath vehicle for any brake fluid leaks
4. Remove wheel chocks

Verification

• With engine off, pump brake pedal 10-15 times. Pedal should feel firm and not sink to floor. Pedal should reach same height consistently.
• Start engine and verify brake pedal does not sink when steady pressure is applied. Pedal may drop slightly initially due to power assist.
• Perform low-speed test drive in safe area. Test brakes at 5-10 mph to verify normal operation before road use.
• Check for firm, consistent pedal feel with no sponginess or excessive travel. If pedal feels soft, repeat bleeding procedure.
• After test drive, recheck master cylinder fluid level and inspect all four bleeder screws and brake line connections for leaks.
• Check brake warning light on instrument cluster - it should NOT be illuminated during normal operation.

More procedures for this vehicle