MB self leveling systems use ONLY MB fluid, don't try other types unless you want to replace ALL of the system.

Here is the problem....over time the coil springs "sag" when that happens the leveling has to work all of the time to keep the car level. That causes undue stress on ALL of the system. The accumulators are the 1st to fail & then the struts.

IF the rear is very stiff.. push down on the trunk opening, & the back of the car should deflect possibly a FOOT or even more. IF not then the accumulators are full of hydraulic fluid & need replaced.

Very important to have the car level with the leveling system NOT functioning. In other words the rear springs need to hold the car level(no weight in trunk OR back seat).

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