My convertible top started acting up today. It wouldn't open or close on its own. But I finally was able to close it top up after a couple of times. I was looking at my fluid level in the cylinder near the pump and it’s a little bit low, just below the Min level with the top up and closed. Is that normal? I don't see any leaks. Do I need to replace the entire thing or can I just add to it up to the Min or Max level? What brand of Hydraulic System Fluid do I use for a 2009 CLK350? Do I unscrew the one bolt and washer then put it back by hand? Is WD40 bad for my top joints? My car has 64,500 miles on it. Thanks.
Hello there. When checking the fluid, the top must be in the service position for an accurate reading. This should show the fluid level at the proper level once the top is in the service position.
The bolt and washer are removed carefully and the Mercedes special tool is used to add or remove fluid. The only approved convertible top fluid is the fluid supplied by Mercedes under their own brand.
WD40 is not a lubricate that is used to remove water and rust, but it is not sufficient for lubrication purposes long term. If the top is continuing to not work, then there is likely another fault other than the fluid level. The most common would be one of the top motors being faulty, a bad top position sensor, or a broken top switch. If you need help having these checked, a certified technician from YourMechanic can come to your car's location to diagnose and repair your convertible top.
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