We've taken our years of German automotive service experience and put it to work for you. Blauparts provides the answers to several FAQs regarding Mercedes-Benz coolant antifreeze. This blog post will discuss recommended Mercedes-Benz antifreeze change intervals, how often you should flush your coolant, and some important tips when filling or topping up your coolant. We will also discuss the importance of using the correct Mercedes-Benz coolant specifications in your vehicle and why you should NOT use use universal coolants or additives.
Please Note: The coolant specifications provided in this article apply to Mercedes-Benz passenger cars, SUVs and vans. The coolant specifications do not apply to heavy duty Mercedes-Benz commercial vehicles such as Detroit or Freightliner semi-tractor trucks.
This Mercedes Benz coolant antifreeze post discusses the following topics:
- Mercedes-Benz Coolant Change Intervals
- What Type of Coolant Does My Mercedes-Benz Use?
- Mercedes-Benz Coolant Antifreeze Specifications
- Topping Up Mercedes-Benz Coolant
Mercedes-Benz Coolant Change Intervals
One of the most frequent questions we get from our customers is how often should I change my coolant?
To maximize corrosion protection and prolong engine life, flushing your Mercedes-Benz coolant antifreeze every 4 to 5 years or every 50,000 - 60,000 miles is recommended.
Why? Due to age and through use the combination of chemical additives contained in coolant and the base of the coolant (even long-life coolant), responsible for lubricating seals, retaining alkalinity and inhibiting corrosion within the engine's cooling system, become depleted. Like oil, your Mercedes-Benz coolant eventually breaks down over time, becomes weak, and "gets dirty." Thoroughly flushing your Mercedes-Benz coolant is most convenient when done while changing the water pump or thermostat. The coolant can also be changed during a scheduled service with a Mercedes-Benz service shop.
Pictured Example - Mercedes-Benz coolant quality specification MB 325.5 (Mercedes-Benz Pink Coolant Part Number A0009892825, Q1030005, BQ1030005). The vehicle had approximately 90,000 miles, which had 1 previous owner. The previous owner had every service record from the date of sale, regular oil changes, preventative maintenance, and took really good care of the vehicle. Note the sediment, contamination, and breakdown of the OE specified coolant that was removed when we thoroughly flushed the system. Even when using approved coolant, years of continuous circulating through the engine causes the base of the coolant and additives to breakdown causing sediment to build up inside the coolant system, creating a contaminated cooling system environment.
Importance of Changing Mercedes-Benz Coolant Antifreeze
There are three main reasons for changing your coolant:
- The first main reason for changing your Mercedes coolant is preventative maintenance. As coolant gets used and depleted of key additives it should be replaced.
- The second reason is the possibility of having the wrong coolant specification or contaminated coolant in your system. The wrong Mercedes coolant or contamination can often be identified by a green, orange, or brown color coolant and should be flushed thoroughly from your cooling system. You'll notice similar warnings in your owner's manual under the coolant section.
- If you just purchased the vehicle and are unsure of the reliability and quality level of the coolant in the engine. If you do not have any service records from the previous owner, it is possible that good preventative maintenance and service has been missed. We recommend creating a new maintenance base line by changing and using the correct coolant.
What Type of Coolant Does My Mercedes-Benz Use?
Owner's Manual - One way to find out what type of Mercedes coolant specification that is recommended for your engine is to look in your owner's manual. Using your appendix found in owner manual look under fluids, coolant or antifreeze. Here you will be directed to an area or specific page number of your owner's manual that should highlight the correct Mercedes coolant specification for your engine.
Visual Inspection - A simple way to find out what type of Mercedes coolant your vehicle uses, is to confirm the coolant color by visual inspection. You always want to use the correct color coolant which correlated to the correct Mercedes coolant formulation for your engine.
Mercedes-Benz has really only used two different types of coolants in their cars, SUVs and vans. A blue or pink violet color coolant. Up to the manufacture date of April 2014 most Mercedes-Benz engines used the blue MB 325.0 and MB 326.0 specification coolant. After April of 2014, Mercedes started using the pink violet MB 325.5 MB 325.6 coolant specification.
Most Mercedes-Benz coolant expansion tanks are black plastic and/or situated in an area where the coolant color isn't visually apparent. This requires that you loosen and remove the coolant expansion tank cap to visually inspect the coolant color inside the expansion tank.
CAUTION: Always wear protective gloves and safety glasses when working with coolant antifreeze. Never remove the coolant expansion tank cap when the engine is hot. If the coolant expansion tank cap is removed while the engine is hot you could be exposed to hot coolant antifreeze that will burn you cause bodily injury. Always check to see what type of coolant is in your Mercedes when the engine has cooled or cold.
Contact Mercedes-Benz Dealer - You can also call your dealer and ask which coolant specification you're going to need. Typically, the dealer will request your vehicle VIN number. In most cases you should also have the year, make, model and engine size available.
Can I Use Universal or Generic Coolant?
No, generic universal coolant antifreeze should never be used in a Mercedes-Benz engine.
Coolants that do not specifically state the correlating Mercedes-Benz coolant quality specification (Example: MB 325.0) for your engine should never be used. These coolants typically are either missing or may contain additives that could have a negative reaction to the engines cooling system. The wrong coolants can contaminate and change the alkalinity and chemical makeup of the engines complete cooling system.
Long-term this can lead to expensive mechanical failures in the engines cooling system. Water pump and water pump seal damage causing coolant leaks and catastrophic engine damage. Other issues can develop such as corrosion, clogging and excessive calcification to the inside of the engine, radiator and heater core. This corrosion to the inside of the cooling system can negatively affect the engines cooling ability restricting coolant flow and causing the engine to run hotter (especially in summer and warmer climates). Over time this can cause overheating issues and possible blown head gaskets.
Other negative effects of using the wrong coolant in your Mercedes can plainly be seen from external indicators. Bulging coolant hoses, white calcified residue and corrosion oozing from coolant hose clamp mating areas, coolant system seal areas, and coolant flange areas.
Mercedes-Benz Coolant Antifreeze Specifications
Specification MB 325.0 MB 326.0 Blue Color Mercedes Coolant - Part Number J4D2022-1
Mercedes Blue Coolant - If the coolant is a blue color this will require coolant quality specification MB 325.0 or MB 326.0 (Mercedes-Benz coolant part numbers A0009890125, A0009890825, A0009890925, Q1030004, BQ1030004). Mercedes coolant specification MB 326.0 is the premix specification and meets all the same specification and OE part number requirements as the MB 325.0 specification mentioned above.
Specification MB 325.5 MB 325.6 Violet Pink Mercedes Coolant - Part Number J4D2126-150-999
Mercedes Pink Coolant - If the coolant is a pink violet color, you will need the MB 235.5 or MB 325.6 coolant specification. (Mercedes-Benz coolant part numbers A0009892825, Q1030005, BQ1030005). Mercedes coolant specification MB 325.6 is the premix specification and meets all the same specification and OE part number requirements as the MB 325.5 specification mentioned above.
Topping Up Mercedes-Benz Coolant
It is possible to have some evaporation of the coolant from the cooling system. This might happen around every 30,000 – 40,000 miles. When the coolant level is low in your Mercedes you will experience a coolant level warning light that will appear on the dash (Instrument Cluster, Gauge Area).
Before topping off your coolant you're going to want your engine to be lukewarm or cold. Do not check the coolant level when the engine is hot because the coolant volume is in an expanded state. Once the engine has cooled access the engine compartment and locate the coolant expansion tank. The coolant expansion tank can be identified by the logo as seen in the picture provided. Remove the coolant expansion tank cap and fill with the appropriate specification coolant up to the max fill indicator marks. Reinstall the coolant expansion tank cap confirming the cap is snug.
(CAUTION: Always wear protective gloves and safety glasses when working with coolant antifreeze. Never remove the coolant expansion tank cap when the engine is hot. If the coolant expansion tank cap is removed while the engine is hot you will be exposed to hot coolant antifreeze that could burn you cause bodily injury. Always check to see what type of coolant is in your Mercedes when the engine has cooled or cold.)
It's Always good to have an extra 1.5 liter of the appropriate Mercedes-Benz coolant specification on had to top up your coolant system.
Maintaining Proper Mercedes Coolant Mixing Ratios
Many Mercedes-Benz coolants sold are a concentrated form. This will require you to mix the coolant with deionized water at a 50% coolant and 50% deionized water ratio. If you do not have deionized water available in your area, it is best to source a Mercedes coolant that is already pre-diluted or mixed to the proper 50/50 mixing ratio with deionized water. This will ensure that the proper PH alkalinity and performance of your engines cooling system is not compromised.
Should Tap Water Be Used for Topping Off Mercedes-Benz Coolant
For all practical purposes no. You should never use tap water in your Mercedes coolant system. Tap water can make the cooling system acidic since it contains a variety of unnecessary mineral, iron, chlorins among others that can negatively affect the coolant system. Long term use of tap water in your cooling system can cause water pump and water pump seal damage, coolant leaks and possible catastrophic engine damage. Other issues can develop such as corrosion, clogging and excessive calcification to the inside of the engine, radiator and heater core.
An Important Warning Note: If you are choosing to take your car to a local quick lube or a non Mercedes-Benz service specialist you will want to confirm they are not adding or topping off your coolant system with the incorrect coolant specification. As noted in the information above, mixing a Mercedes coolant specification with generic universal coolant antifreeze will cause an adverse chemical reaction with the existing coolant and contaminates the cooling system.
The only reason to top off your coolant system with water is for emergency reasons. If your engine is low on coolant and you're in a situation or area where the correct Mercedes-Benz specification coolant is not available, it would be better to use bottled water, distilled water or deionized water to top off the coolant then to continue running the engine with low coolant. It would also be better to use bottled water, distilled water or deionized water to top up the coolant then to use the incorrect coolant specification. However, this will result in a weak coolant freeze point. If you are in an area that sees frequent freezing temperatures your vehicle should be stored in a heated building until your coolant system can be flushed and serviced to restore the coolant system back to its factory intended antifreeze strength and performance levels. Our recommended coolant mixing ratio is 50% deionized water and 50% coolant or also known as a 1:1 ratio. This will give you the coolant strength of -40°C or -40°F. If you do live in a colder climate where -40°C / -40°F is seen often, please resort to your owner's manual for a stronger antifreeze mix ratio.
As mentioned above, we recommend always having an extra 1.5 liter bottle of the appropriate Mercedes-Benz coolant specification on hand or in your trunk to top up your coolant system.
Should Coolant Additives, Conditioners and Flushing Agents Be Used in Mercedes-Benz Coolant?
Coolant Performance Improving Additives
Coolant Antifreeze performance improving additives are unnecessary. If someone is requesting that you use a coolant system performance improvers it should be held in question. The OEM Mercedes-Benz coolant quality specifications and formulations already contain the correct additive ratios to optimize the performance of your cooling system. Mercedes-Benz has performed more cooling system testing to optimize flow, cavitation, corrosive alkalinity and temperature control. The only reason to use a coolant performance improver is if the coolant is old and past its service life expectancy. A coolant performance improver can temporarily be used until you have the time to perform a proper coolant system flush with the correct Mercedes-Benz coolant spec.
Cooling System Flush Additives
Many coolant flushing agents contain muriatic and/or other acids. Remnants of these acids left in the cooling system can lower the longevity of your Mercedes-Benz cooling system components. Many of these flushing additives can have a long-term negative effect on plastic, rubbers and seals used in the engines cooling system. To correctly flush your engines cooling system, we recommend using large amounts of water rather than coolant flushing additives.
Coolant Stop Leak Sealing Additives
When a coolant stop leak or sealing conditioner additive is used typically it's because of an underlying mechanical issue with the engine. These additives are used to slow coolant gasket and seal leaks or minimize the effects of a blown head gasket. Using coolant stop leak or sealing additive would be a temporary fix or patch to the real problem. We recommend correctly fixing the root of the coolant system issue before ever using coolant stop leak or sealing conditioner additive. Also, one of the major downfalls of using coolant stop leak or coolant sealing conditioner additives is the future repercussions. Many of these additives use solids that can't be completely removed from the cooling system. Even after excessive flushing. The solids from cooling system stop leak additives clog radiators, heater cores and other areas of the cooling system lowering the efficiencies of the cooling system. Once again, we always recommend fixing the coolant system issue correctly before ever using coolant stop leak or sealing conditioner additives.