Power Steering Fluid Flush

This procedure flushes the power steering system to remove old contaminated fluid and replace it with fresh ACDelco Power Steering Fluid, improving steering performance and extending component life.

Warnings

Tools required

Parts

• Power steering reservoir cap O-ring (if damaged) × 1 — Use OEM specification

Fluids

• ACDelco Power Steering Fluid — 2 qt

Preparation

1. Park vehicle on level ground and apply parking brake
2. Place wheel chocks behind rear wheels
3. Raise front of vehicle with floor jack and secure on jack stands under frame rails
4. Allow engine to cool to ambient temperature if recently operated
5. Locate power steering fluid reservoir on driver side of engine compartment near firewall
6. Clean area around reservoir cap to prevent contamination

Procedure

1. 1

   Remove old fluid from reservoir
   Remove the power steering reservoir cap. Using a turkey baster or fluid transfer pump, extract as much old fluid as possible from the reservoir. Transfer the old fluid to a drain pan. Continue until the reservoir is as empty as possible without removing the reservoir from the vehicle.
2. 2

   Fill reservoir with fresh fluid
   Using a funnel, fill the power steering reservoir with fresh ACDelco Power Steering Fluid to the COLD MAX line marked on the reservoir. Reinstall the reservoir cap temporarily.
3. 3

   Cycle steering to circulate fluid
   With the engine OFF, turn the steering wheel fully left and then fully right 10-15 times. This circulates fresh fluid through the system and pushes old fluid back to the reservoir. Turn the wheel slowly and pause briefly at each extreme. Do not force the wheel past the steering stops.
4. 4

   Remove diluted fluid from reservoir
   Remove the reservoir cap and check the fluid level and condition. The fluid will now be a mixture of old and new fluid. Use the turkey baster or transfer pump to remove as much fluid as possible from the reservoir again. The fluid color should be noticeably darker than fresh fluid.
5. 5

   Refill and repeat cycling process
   Refill the reservoir to the COLD MAX line with fresh ACDelco Power Steering Fluid. Repeat the steering wheel cycling process (full left to full right 10-15 times with engine OFF). This is the second flush cycle.
6. 6

   Perform final fluid extraction
   Remove the reservoir cap and extract the fluid again. Compare the color to fresh fluid from the bottle. If the fluid is still significantly darker than new fluid, repeat steps 5 and 6 one more time. For most applications, 2-3 complete flush cycles will result in clean fluid.
7. 7

   Fill to proper level and start engine
   Fill the reservoir to the COLD MAX line with fresh fluid. Start the engine and let it idle. Check the fluid level and top off as needed to maintain proper level. The fluid level may drop as the pump circulates fluid through the system.
8. 8

   Purge air from system
   With the engine idling, slowly turn the steering wheel fully left and then fully right 3-4 times. Do not hold the wheel against the stops for more than 2-3 seconds. Monitor the reservoir and maintain fluid level at the COLD MAX line, adding fluid as necessary. The fluid may appear foamy initially as air purges from the system.
9. 9

   Check for leaks and proper operation
   With the engine running, inspect all power steering line connections, the pump, and steering rack for leaks. Turn the steering wheel and verify smooth operation with no unusual noises. If whining or groaning is heard, air may still be in the system; continue cycling the steering wheel slowly until noise subsides.
10. 10

    Final fluid level check
    Turn off the engine and allow it to sit for 2-3 minutes. Check the fluid level with the engine off. The level should be at or slightly above the COLD MAX line. Top off if necessary. Reinstall the reservoir cap securely and wipe away any spilled fluid from surrounding components.

Reassembly

1. Lower vehicle from jack stands using floor jack
2. Remove jack stands and wheel chocks
3. Dispose of used power steering fluid properly at a recycling center or automotive shop that accepts used fluids

Verification

• Start engine and verify smooth, quiet power steering operation with no whining or groaning noises
• Turn steering wheel fully left and right to verify full range of motion and proper assist
• Check fluid level with engine at operating temperature; level should be between COLD and HOT marks
• Verify no leaks are present at reservoir, pump, lines, or steering rack
• Test drive vehicle and confirm normal steering feel and response during turns and parking maneuvers

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