When I completed my scheduled “A-(self)-Service” a couple months ago, I noticed the coolant reservoir level was at the “MIN” line, about an inch below the “MAX” line. (The coolant reservoir is on the passenger side of the engine compartment, and the level lines are viewable on the inboard side of the vessel.) Not wanting a “Low Coolant” warning light to occur at the worst possible time, I set out to purchase some antifreeze to bring up the level. Like every other automotive consumable, antifreeze has proliferated from a single generic ethylene glycol product into seemingly dozens of custom cocktail blends, of which only one (of course) is suitable for the car you own.

MB’s spec for the G and other current models is “325.5/325.6” about which you can find more information at https://bevo.mercedes-benz.com/bevolisten/325.5_en.html. Fortunately, one of the MB spec compatible coolants is Zerex G40, available at most auto stores, and easily identifiable by its pink label and cap, and by the appearance of “Mercedes-Benz” at the top of the front label (the “MB-Approved 325.5, 325.6” in on the backside label in small print). This product is already mixed with water at the requisite 50/50 ratio, and can be added directly to the coolant reservoir. The gallon container costs about $20. Bringing the coolant level up to MAX took only about a pint. If you plan to do any heavy-duty towing, keeping a jug in your G might be prudent.