310.1   Coolant Specifications

Select Sheet 
Overview  

Note: These specifications apply to the Mercedes-Benz, Maybach, AMG, smart, and Setra brands.

WARNING

The tasks that the anti-corrosion agents/antifreezes, coolants, or coolant additives have to perform are as important as those of a structural component. Products and brands that are not mentioned in the following Specifications for Operating Fluids sheets do not have MB approval and can lead to significant restrictions in the engine output and/or irreparable damage to the engine cooling system.

1. Terms used

Antifreeze with corrosion inhibitor:

Component of the coolant for combustion engines as corrosion and antifreeze protection, for lowering the freezing point as well as raising the boiling point. Can also be called "concentrate". Must be used with water as per chapter 3.1.

Coolant:

Mixture of antifreeze with corrosion inhibitor and water for cooling engines. Coolants normally consist of antifreeze with corrosion inhibitor and water.

Coolant additives:

Anticorrosion agent that can be used for special applications mixed with water. The mixture has no antifreeze protection!

MB approval:

Marking of the coolants or antifreezes with corrosion inhibitor that are tested by Daimler AG and approved for the corresponding use, see table 1 and 2. On the containers with tested brand-name products, you will find MB approval 325.0, for example, as a note.

2. Overview

Tables 1 and 2 provide an overview on the use of the approved anti-corrosion agents/antifreezes and the maximum change intervals. These coolants have the following characteristics:
  • Ensure heat transfer
  • Long-term corrosion and cavitation protection for all components of the cooling system
  • Ensure antifreeze protection
  • Increase boiling point
  • Resistant against microorganisms
  • Effective foam suppression
Vehicles with a combustion engine are defined in the assignment via the engine model series, see Tables 1 and 2.

The sheet numbers 325.x show the antifreezes with corrosion inhibitor. These must be mixed with water before use as per chapter 3.1.

The sheet numbers 326.x show the ready-mixed coolants. These must not be mixed with water.

Products from the Specifications for Operating Fluids sheets 325.7/326.7 are not compatible with products from other Specifications for Operating Fluids sheets. Vehicles with a fuel cell require a special coolant for cooling the fuel cell.

Coolants for fuel cell vehicles must only be refilled in an F-Cell support point.
Table 1: For passenger cars and vehicles with passenger car combustion engines

Sheet No.
Change interval years/km
Whatever applies first must be observed.
325.0 or 326.0
325.6 and/or 326.6
325.7 or 326.7
Major assembly model series
M1xx/M2xx
OM200.71 in model series 415 (Citan)



4 years/160,000 km
OM200.72 in model series 470 (X-Class)



4 years/120,000 km
M281 in model series 453.0/3/4 (smart)



6 years/60,000 km
All others M1xx/M2xx



15 years/250,000 km
OM6xx
OM607 in model series 415 (Citan)



4 years/160,000 km
OM699.77 in model series 470 (X-Class)



4 years/120,000 km
All others M6xx



15 years/250,000 km
Comment
For all vehicles with a manufacturing date up to and including April 2014
Usable for all vehicles
Not compatible with products from sheet 325.0/6 and 326.0/6
Exception: Different change intervals are specified in the vehicle maintenance manual.

Table 2: For vehicles with commercial vehicle engines
Sheet No.
Major assembly model series without secondary water retarder (SWR)
Major assembly model series with secondary water retarder (SWR)
Change interval in years
Whatever applies first must be observed.
OM300
OM400
OM904 up to 926
OM934, 936
OM457, 460
OM500
OM470 up to 473
311.0








0.5 years
312.0








1 year
325.0 or 326.0








3 years
325.3 or 326.3








5 years
325.5 or 326.5








3 years
325.5 or 326.5








2 years/2nd oil change

Coolants or anti-corrosion agents/antifreezes that are listed on different sheet numbers in Tables 1 and 2 must not be mixed with each other, as considerably reduced anti-corrosion protection and/or considerable incompatibility may irrevocably damage the engine cooling system.

3. Coolant

The coolants and anticorrosion/antifreeze agents are based on ethylene glycol as the antifreeze component but differ with regard to the remaining ingredients, e.g. for corrosion protection, table 3.
Table 3: Specifications for Operating Fluids sheet number and coolant type
Coolantsheet no.
Antifreeze with corrosion inhibitor sheet no.
Inhibitors
Free of
inorganic
organic
326.0
325.0
Si, B
X
Nitrite, amine, phosphate
326.3
325.3

X
Nitrite, amine, phosphate, borat, silicate
326.5
325.5
SI
X
nitrite, amine, phosphate, borat, 2-ethylhexanoic acid
326.6
325.6
SI
X
nitrite, amine, phosphate, borat, 2-ethylhexanoic acid
326.7
325.7

X
Nitrite, amine, borate, silicate

3.1. Mixing ratio

All coolants from sheets 326.x are ready-to-use mixtures. These must not be mixed with additional water.

In contrast, all anti-corrosion agents/antifreezes from sheets 325.x must be used with approx. 50% by volume of water, this corresponds to antifreeze protection down to -37 °C. The water quality must satisfy the requirements in the following chapter.

Even with extremely low ambient temperatures, not more than 55 vol.-% antifreeze with corrosion inhibitor is to be used. With 55 % by volume of antifreeze with corrosion inhibitor, the max. antifreeze protection (approx. –45 °C) of an aqueous ethylene glycol solution is reached. A higher antifreeze with corrosion inhibitor rate reduces the antifreeze protection and the heat dissipation in the engine, this can lead to irrevocable damage.
Table 4: Target concentration of antifreeze with corrosion inhibitor and water
Sheet No.
Mixing ratio
Concentrate % by volume
Water % by vol.
325.0
50
50
325.2
50
50
325.3
50
50
325.5
50
50
325.6
50
50
311.0
1
99
312.0
10
90
325.7
50
50

In special cases (commercial-vehicle engines, no antifreeze specification) coolant additives can be used that are primarily corrosion protection additives.

4. Water quality

Clean and the softest possible water should be used for processing the coolant. Drinking water often satisfies the requirements. Information concerning the water quality of drinking water is available from the local water-plant authorities or the official water utilities on request.

If there is no available information regarding the water quality or if no suitable water is available, then distilled or deionized water should be used to prepare the coolant. Sea water, brackish water, brine and industrial waters are not suitable. Salts may promote corrosion or form disruptive deposits.

The analysis values of the water for mixing coolants must be within the limits of table 5.
Table 5: Water quality
Water quality
min
max
Earth alkali ions
mmol/l

2,7
Hardness
°dH

15
Chloride
mg/l

80
Chloride + sulfate
mg/l

160
pH-value
-
6,5
8,0

1°dH = 0.1783 mmol/l alkaline earth ions = 7.147 mg/l Ca2+ or 4.336 mg/l Mg2+

With the use of premixed coolant, compliance with the concentration (50/50) must also be observed in addition to the MB approval.

4.1. Coolant additives for commercial vehicle engines without antifreeze specification

In climate zones free of frost all year round, no antifreeze protection is required as the engine cooling systems are adapted to coolant according to sheets 325.x and 326.x. Only in justified exceptional cases an aqueous solution with corrosion protection should be used. The use of anti-corrosion agents in water is limited to the engines named in Table 2. The use of anticorrosion oil emulsion according to sheet 311.0 is limited thermally. The emulsion must therefore not be used in efficient modern engines.

Mixtures of different products as stated in sheet 311.0 and 312.0 are not permitted.

The following must be observed when creating anticorrosion oil emulsion according to sheet 311.0:

When carrying out a new filling (initial filling or filling after a cleansing operation), an emulsion of 1.0 - 1.5 % by volume must be used. When refilling, an emulsion of 0.5 - 1.0 % by volume should be used. Concentrations that are too high (>1.5 % by volume) do not improve the corrosion protection, but rather exert a negative influence on seals and hoses.

5. Monitoring coolant operation

During operation, the corrosion inhibitors of the coolant are consumed and the mixing ratio may change due to water evaporation. It is therefore very important to regularly monitor the coolant if the engine is to run trouble free.

The inspection of the mixing ratio should be conducted with suitable apparatus. To do so, the density can be used to determine this in accordance with picture 1 or the refractive index in accordance with picture 2. The specifications on the mixing ratio may vary slightly for individual coolants from the values in pictures 1 and 2.
P00.40-2032-01_MULTILANGUAGE_gif.gifP00.40-2032-01
Bild 1: Density of KFM/water mixtures
P00.40-2033-01_MULTILANGUAGE_gif.gifP00.40-2033-01
Bild 2: Refractive index of KFM/water mixtures


If the coolant contains less than 45% by volume or more than 55% by volume of antifreeze with corrosion inhibitor, the mixing ratio must be immediately corrected. To calculate the refill quantity, the following calculation aid can be used:

Calculation of coolant quantity to be added for low concentration (Specified: 50 Vol.-%)

  • Coolant content (total) in liters
  • Measured concentration in Vol.-%
Computational formula:
  • (50 - measured concentration) * coolant content / (100 - measured concentration) = top-up quantity for corrosion/antifreeze
Example of calculation:
  • Coolant content (total) = 8 liters
  • Measured concentration = 36 Vol.-%
  • (50 % - 36 %) * 8 l / (100 % - 36 %) = 1.75 liters
This calculated quantity should normally be drained off beforehand
Refrigerant protection/concentration table (approx.)
°C
–9
–12
–16
–20
–25
–32
–37
vol %
20
25
30
35
40
45
50

6. Disposal of coolants

The coolants are biologically-degradable material. The statutory regulations or waste water ordinances in each individual country must be observed when disposing of used coolant. It is recommended to have the possibilities available for disposing of materials explained by the local responsible water authorities.