Mercedes Power Steering Pulsation Damper - Genuine Mercedes 0004660400

This is my 2nd time since owning my 07 MB CL550 that I've had to replace the Pulsation Damper on the ABC tandem pump. When you hear the moaning sound coming from the pump always be sure to replace the Pulsation Damper ball at the top of the pump first! This will silence all the noise you have been hearing. Now the only exception to not doing the Damper first is if you blew out an ABC hose and lost all of the Hidrolik fluid and you continued to drive the car with a dry pump! Then you can count on having burned up the pump assembly. If you ever blow out an ABC hose and lose a lot of fluid, shut down the car and phone a flat bed to tow it! Never drive it, not even 2 miles with a dry pump! They are not cheap. The tow is cheaper! I've spent my lifetime as a Mercedes Benz technician, take it from a pro. Repair all leaks, inspect the entire system, replace the fluid by flushing the ABC fluid and also putting in a new reservoir filter in and also replace the damper ball. On average they will go bad every 5 years or so. Just verify the noise with a mechanic's stethoscope at the pump body. Then order your part from FCP Euro and enjoy a lifetime warranty! Happy driving! Go with the best FCP Euro! Technician tip: Remove the belt, then remove the top pump bolt completely and carefully pry between the pump body near the front and the engine. You will get just enough room to be able to remove the Damper ball. Add a small amount of oil or Vaseline to the O-ring on the new ball before screwing it in by hand to get the threads started. Then use a socket/extension/ratchet to tighten to 25 ft lbs torque. Assemble in reverse order. Enjoy doing it the easy way. Oh yeah, only do at your own risk. Advice is free but not guaranteed. Work smart and be safe. Fill the system and enjoy the silence of your new Damper assembly!

Installed it 15k miles ago and still going strong.

My CL63's had whining sounds from 1500-2700 rpm. Reading the online forums said replacing the pulsation damper which is on your ABC pump would fix the issue along with an ABC flush. Sure enough it did and my car rides so much better now. To prevent damage to your ABC system, flush the ABC fluid every 30-40K miles. My fluid was black when it came out, new fluid is clear-green. When you purchase this part, you can either get a new part which is $450 from the dealership or you can buy this which is remanufactured around $150 after the core charge is removed. It's a no-brainer. Have no regrets buying this part.

Buy this before you throw any other parts at your ABC suspension and twin pump. I was having all sorts of groaning sounds and clicking noises from the pump area on my S600 and thought for sure I was looking at a pump replacement. After some digging on the internet it seems that this is considered a "wear item" and it will loose effectiveness over time. Install is easy. On my V-12 I simply removed the driver side "snorkel" that runs to the air box. 17mm socket and extension to loosen the old one and slap the new one on. If you can change a light bulb, you can do this. Be sure to clean the area REALLY well before removal (I used brake cleaner and blasted the whole area). This thing does ship with a thread cover that screws off, so don't freak if it doesn't match your old one (like I did). Good luck!