Engine Coolant Mixing Compatibility
I used on my car the following engine coolant: Mercedes Benz BQ1030004 (anticorrosion/antifreeze AGENT Blue color) - Spec 325.0, which required mixture with water.
Hence, in the future, in case I need to add coolant, can I mix the above with other brands' coolant that meets the specs, such as G48 Zerex?
Furthermore, is there any document describing the compatibility of different coolants?




On another note, I am confused with the change interval. The MB maintenance manual suggests once per 150K miles without stating any time constraints. However on the labels of the fluids (for example on Zerex G48) it mentions that it lasts 150K miles or 5 years. Hence are we sticking to the 150K miles only or should we consider the 5 years as well?




You will get plenty of views on coolant change intervals. Depending on the brand you use, common theory is somewhere between 2 to 4 years for normal driving. Some believe coolant lasts 12 years. I don't and I'd say most people don't. Build a schedule to change every 40k miles the transmission fluid (including convertor - if your's has the extra drain plug) transfer case, diff oils and coolant like that and youll be happy. Brake fluid every 2 years. Power Steering reservoir and fluid should be looked at but probably not as often.
I change my engine oil every 5k miles so im probably a bit **** on that, but listen to the experts and that's what they do, so who am I to say no? Even if this is a bit of overservicing, it's not going to kill you car. Waiting too long will.
Search this forum - you'll find plenty of experiences and opinions.
Last edited by BlackML550; Feb 4, 2023 at 04:09 AM.
Their antifreeze brand is Glysantin and their formulas are preceded by the letter G.
G48 is the correct formula for Mercedes up to 5/14 production and the color is always blue.
After 5/14 (not applicable to W164) pink G40 is installed.
In the USA, Zerex/Valvoline does a nice job of using G formula labeling and their formulas are the same as Glysantin and compatible.
There is no such thing as an "all vehicles" formula despite misleading, incorrect hype.
Earliest W164 arrived with Gold G05. Gold antifreeze is no longer available from Mercedes. Most W164 that came with Gold G05 are due the 15 year antifreeze change, assuming they haven't reached 150k miles. It's acceptable to replace gold with blue, as they are compatible. Mixing the two is not smart.
Last edited by lkchris; Feb 7, 2023 at 07:31 PM.



