Instructions on replacing the power steering pump or the power steering reservoir on Mercedes-Benz V6 and V8 cylinder engines, such as the M112 and M113 engines. Symptoms of power steering failure include:

• Whining or squealing noises
• The steering wheel is difficult to turn
• Loss of steering assist

Before replacing a power steering pump, ensure you have not lost power steering fluid. Check out this video if you need help checking the power steering fluid. If your fluid level is low, use Mercedes-Benz Power Steering Fluid. Low power steering fluid will cause a whine, especially when you turn your steering wheel. Even a small leak should be located and repaired. Running the system low can damage the pump, and topping off is not a permanent repair.

W163 ML-Class steering noise: Mercedes-Benz issued a technical bulletin for squeaking or squealing from the steering rack while turning. Confirm the applicable chassis codes before following the bulletin. Technical Bulletin for the steering issues, such as squeaks and squeals from the area of the rack and pinion when turning the steering wheel left and right. According to Mercedes-Benz, this noise comes from insufficient lubrication at the shaft sealing ring in the control head. The dealer’s solution is to remove 50 ml of power steering fluid and replace it with 50 ml of Lubrizol 6178.  Technical Bulletin Order No.: T~B~46.20/31h. Supersedes: T-B–46.20/31a 

DO IT YOURSELF

Video

How to replace the power steering Pump, Reservoir, and Driver Belt tensioner on a Mercedes-Benz.

Instructions

Tools you will need:

• External Torx socket set
• Screwdrivers
• 17 mm deep socket or wrench to release the belt tensioner
• Torx sets such as these.

Instructions: 

1. Cool the engine, set the parking brake, chock the wheels, disconnect the negative battery cable before disturbing a ground strap, place a drain pan below the pump, protect the alternator from fluid, and dispose of used hydraulic fluid properly. Remove the serpentine belt. See the Mercedes-Benz serpentine belt replacement guide and video here. 

2. Open the power steering fluid reservoir and extract all the power steering fluid.

3. Detach the return line from the power steering reservoir housing.
   

4. Unbolt the high-pressure line. Take care not to damage the small O-ring when removing the line.

5. Use a flat screwdriver to pull out the C-shaped locking ring on the back of the power steering reservoir.
   
   

   

6. Remove the bolt on the front of the power steering reservoir.
   
   

7. Remove the two bolts on the back of the power steering pump. They are a pain to get to, but you can do it.  You can use a 3/8 ratchet wrench on the rear bolts if you have a ratcheting wrench like this. A ratcheting wrench can save time in the limited space.

   

   

   

8. Remove the two E-torx bolts on the front of the power steering pump.
   

9. Remove the attachment arm from the old power steering pump and attach it to the new power steering pump. Note: You can also leave the arm attached to the engine and unbolt these bolts directly from the power steering housing. If you go this route, you must unbolt the two bolts through the power steering pulley.

10.  A ground wire may also be connected to the power steering pump. If you are having difficulty getting to that bolt, don’t bother taking that off until you have the power steering pump loose. Once the power steering pump bolts are loose, you can move the power steering pump and loosen the ground bolt.
    

11. Reinstall in reverse order. Ensure you reinstall the O-rings for the return line and where the reservoir connects to the power steering pump.
    
    
    

12. Refill the power steering system with the fluid specification approved for the vehicle, or use Febi Bilstein Power Steering Fluid.
    

13. Bleed the system, verify the fluid level, and check every connection for leaks.

14. Congratulations! You are done.

Related Article:

• Power Steering Pump Replacement Mercedes Benz Youcanic

INTERCHANGE PART NUMBERS:

86-01183 AN , 0034666001 , 003466600160 , 003466600180 , 003466600188 , 004 466 14 01 , 004 466 14 01 88 , 0044661401 , 004466140160 , 004466140180 , 004466140188 , 0044661401-88 , A0034666001 , A003466600160 , A003466600180 , A003466600188 , A0044661401 , A004466140160 , A004466140180 , A004466140188

APPLICATIONS: 

• 2005-2006 Chrysler Crossfire Base 6-cylinder 3.2L 195CID Power Steering Pump
• 2005-2006 Chrysler Crossfire Limited 6-cylinder 3.2L 195CID Power Steering Pump
• 1998-2000 Mercedes-Benz C280 Base 6-cylinder 2.8L Power Steering Pump
• 1998-2000 Mercedes-Benz C43 AMG Base 8-cylinder 4.3L Power Steering Pump
• 2002 Mercedes-Benz CL55 AMG Base 8-cylinder 5.5L 335CID Power Steering Pump
• 1998-2002 Mercedes-Benz CLK320 Base 6-cylinder 3.2L Power Steering Pump
• 2003 Mercedes-Benz CLK320 Base 6-cylinder 3.2L Power Steering Pump
• 1999-2003 Mercedes-Benz CLK430 Base 8-cylinder 4.3L Power Steering Pump
• 2002 Mercedes-Benz CLK55 AMG Base 8-cylinder 5.5L 335CID Power Steering Pump
• 1998-2002 Mercedes-Benz E320 4Matic 6-cylinder 3.2L Power Steering Pump
• 1998-2002 Mercedes-Benz E320 Base 6-cylinder 3.2L Power Steering Pump
• 2000-2002 Mercedes-Benz E430 4Matic 8-cylinder 4.3L Power Steering Pump
• 1998-2002 Mercedes-Benz E430 Base 8-cylinder 4.3L Power Steering Pump
• 1999-2000 Mercedes-Benz E55 AMG Base 8-cylinder 5.5L 332CID Power Steering Pump
• 1999-2002 Mercedes-Benz E55 AMG Base 8-cylinder 5.5L 335CID Power Steering Pump

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