Brake Bleed - All Four

This procedure removes air from all four brake lines using the manual bleeding method to restore firm brake pedal feel and proper braking performance.

Warnings

Tools required

Parts

• ACDelco DOT 4 Brake Fluid × 1 — ACDelco 19350787 or equivalent DOT 4

Fluids

• ACDelco DOT 4 Brake Fluid — 1 qt

Preparation

1. Park vehicle on level surface and place wheel chocks behind rear wheels
2. Verify engine is cool and transmission is in Park with parking brake released
3. Open hood and locate brake fluid reservoir on driver side of firewall above master cylinder
4. Check reservoir fluid level - top off to MAX line with fresh DOT 4 brake fluid if low
5. Loosen all four wheel lug nuts 1/4 turn while vehicle is on ground
6. Raise vehicle using floor jack at front and rear manufacturer jacking points
7. Support vehicle securely on four jack stands at frame rails - test stability before working
8. Remove all four wheels completely and set aside
9. Inspect all four brake calipers for leaks or damage - repair any issues before bleeding
10. Prepare bleeding setup: attach 12-inch length of clear vinyl tubing to fit snugly over bleeder screw nipple, place other end in clean waste container
11. Have assistant available or prepare for one-person bleeding method using tubing submerged in fluid

Procedure

1. 1

   Prepare master cylinder reservoir
   Using turkey baster or extraction syringe, remove old brake fluid from reservoir until approximately half empty. Dispose of old fluid properly. Refill reservoir to MAX line with fresh DOT 4 brake fluid from newly opened container. Leave reservoir cap off but keep fluid bottle handy. Clean any spilled fluid from reservoir exterior immediately.
   ⚠Old brake fluid may contain moisture and contaminants. Removing some old fluid improves the bleeding process.
2. 2

   Bleed right rear caliper (passenger side rear)
   Bleeding sequence for this vehicle is: RR (right rear), LR (left rear), RF (right front), LF (left front). Locate bleeder screw on top rear of right rear caliper. Clean bleeder screw and surrounding area with brake parts cleaner. Attach clear vinyl tubing to bleeder screw with other end submerged in 1-2 inches of clean brake fluid in waste container. Have assistant pump brake pedal 5-6 times and hold firm pressure. While pressure is held, open bleeder screw 1/2 to 3/4 turn using 10mm wrench. Fluid and air will flow through tubing. When flow stops and pedal reaches floor, close bleeder screw firmly. Release pedal. Repeat this pump-hold-open-close sequence 4-6 times until no air bubbles appear in tubing and only clean fluid flows. Check reservoir level frequently and add fluid to maintain level above MIN line.
   ⚠️Never allow brake pedal to be released while bleeder screw is open or air will be drawn back into system.
   ⚠️Monitor reservoir constantly. If it runs dry, air enters master cylinder requiring complete system re-bleed.
   Torque spec

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

   Bleed left rear caliper (driver side rear)
   Move to left rear caliper. Check and top off reservoir to MAX line. Clean bleeder screw area. Attach tubing to left rear bleeder screw with opposite end submerged in fresh fluid in container. Repeat exact bleeding sequence from Step 2: pump pedal 5-6 times, hold pressure, open bleeder 1/2 to 3/4 turn, allow fluid to flow until pedal hits floor, close bleeder, release pedal. Continue until no air bubbles visible and only clean fluid flows. Typically requires 4-6 pump cycles. Tighten bleeder screw to specified torque.
   ⚠️Reservoir level drops faster when bleeding rear brakes. Check level after every 2-3 pump cycles.
   Torque spec

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

   Bleed right front caliper (passenger side front)
   Move to right front caliper. Top off reservoir to MAX line. Locate bleeder screw on top inboard side of caliper. Clean bleeder screw area thoroughly. Attach tubing to bleeder with opposite end submerged in clean fluid. Repeat bleeding sequence: pump pedal 5-6 times firmly, hold pressure, open bleeder screw 1/2 to 3/4 turn, allow fluid flow until pedal reaches floor, close bleeder screw, release pedal. Continue until only clear bubble-free fluid flows. Front calipers may require more cycles (6-8) due to longer brake lines. Monitor reservoir level constantly.
   ⚠Front brake lines are longer and may contain more air, requiring additional bleeding cycles.
   Torque spec

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

   Bleed left front caliper (driver side front)
   Move to left front caliper (final wheel). Top off reservoir to MAX line. Clean bleeder screw area. Attach tubing to left front bleeder screw with opposite end submerged in clean fluid in container. Repeat bleeding sequence: pump pedal 5-6 times firmly, hold pressure, open bleeder 1/2 to 3/4 turn, allow fluid to flow until pedal reaches floor, close bleeder, release pedal. Continue until absolutely no air bubbles visible in tubing and only clean fluid flows. Typically requires 6-8 pump cycles. Tighten bleeder screw to 10 Nm (7 lb-ft) - do not overtighten as bleeder screws are easily damaged.
   ⚠This is the final wheel - ensure absolutely no air bubbles remain before proceeding.
   Torque spec

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

   Perform secondary bleed sequence verification
   After completing all four wheels once, top reservoir to MAX line. Return to right rear and repeat bleeding process for 2-3 pump cycles at each wheel in same sequence (RR, LR, RF, LF) to ensure any residual air is purged. This secondary sequence should produce no visible air bubbles. If bubbles still appear, continue bleeding that corner until clear. Verify all bleeder screws are tightened to 10 Nm (7 lb-ft) torque.
   ℹ️Secondary bleeding pass ensures complete air removal from system, especially important after brake component replacement.
   Torque spec

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

   Clean brake components and reinstall wheels
   Remove vinyl tubing from all bleeder screws. Spray all caliper areas with brake parts cleaner to remove any spilled brake fluid. Wipe clean with shop towels. Inspect all bleeder screws for tightness and verify no leaks. Fill master cylinder reservoir to MAX line with fresh DOT 4 fluid and install reservoir cap securely. Inspect all four brake rotors, pads, and calipers for proper condition. Reinstall all four wheels, hand-threading lug nuts clockwise to prevent cross-threading.
   ⚠Brake fluid residue on rotors or pads will cause noise and reduced braking. Clean thoroughly.
8. 8

   Lower vehicle and torque wheels
   Lower vehicle partially so tire weight prevents rotation but vehicle is not fully on ground. Torque all wheel lug nuts to 140 Nm (103 lb-ft) using star/cross pattern (tighten opposite lug nuts in sequence, not adjacent). Fully lower vehicle to ground and remove jack stands and floor jack. Perform final lug nut torque verification in star pattern to ensure even seating.
   Torque spec

   Wheel Lug Nuts140 Nm (103 lb-ft)
9. 9

   Perform brake pedal firmness test
   With engine OFF, pump brake pedal 10-15 times firmly. Pedal should become progressively firmer and achieve solid resistance within 3-4 inches of travel from released position. Pedal should NOT sink to floor or feel spongy. If pedal is soft or sinks, air remains in system - repeat bleeding procedure. Start engine (power brakes active) and verify pedal height is normal with firm resistance. Press firmly and hold for 30 seconds - pedal should not slowly sink.
   ⚠️DO NOT DRIVE if brake pedal feels soft, spongy, or sinks to floor. This indicates air in system or brake system failure. Re-bleed or seek professional service immediately.

Reassembly

1. Verify master cylinder reservoir is filled to MAX line and cap is installed securely
2. Confirm all four bleeder screws are tight at 10 Nm (7 lb-ft) with no fluid leaks visible
3. Ensure all wheels are torqued to 140 Nm (103 lb-ft) in proper star pattern
4. Dispose of used brake fluid according to local regulations - do not pour down drain or onto ground
5. Clean all tools and work area of brake fluid residue

Verification

• With engine off, pump brake pedal - should achieve firm resistance within 3-4 inches of travel and not sink to floor
• Start engine and verify pedal height is normal with power assist active
• Check for brake fluid leaks at all four bleeder screws and around calipers
• Verify master cylinder reservoir is at MAX line with cap secure
• Perform low-speed test drive in safe area - brake pedal should be firm with immediate response and no pulling to either side
• Test brakes at 5-10 mph with moderate then firm pressure - vehicle should stop smoothly without pedal fade or sponginess
• After test drive, recheck reservoir level and inspect all bleeder screws for seepage
• If ANY abnormal pedal feel, noise, pulling, or reduced braking exists, DO NOT DRIVE and diagnose issue immediately

Related trouble codes on this vehicle

Codes that commonly send this job to the bay — tap one for symptoms, causes, and diagnostic steps.

Chasing one of these codes and not sure which part is guilty? Ask a master mechanic about YOUR car →

More procedures for this vehicle