mis3

Just talked to MB dealer, the Parts department told me that the w209 coolant should be changed every 250K KM or 15 years.

Does this mean sense?

I am thinking to change it myself. How many jugs do I need?

KENNY94945

Dexcool - the red coolant - states to change at 5 years. Yet there seems to be an issue with sediment and that antifreeze. So IMHO chage the red and the green at three years.
Never mix the two or change from one to the other.
15 years...doesn't seem correct.

I do not have a factory manual available to help with capacities or DIY.

RLE

The W204 manual says change at 15 years because there is a "teabag" of additives in the overflow tank. i would verify that this applies to other models.

BTW, if you don't want to buy MB coolant, you can buy Zerex GO-5 which is the same thing and is approved.

You are risking corrosion to the radiator and the rest of the cooling system if you use anything else and that includes Dexcool and it's ilk.

mis3

I am looking at the Service Book now.

At approx. every 250,000 km or 15 years
2080 Replace coolant (water/anticorrosion/antifreeze mixture).....

If I change the coolant, I plan to buy the MB one from the dealership. For MB coolant, I believe I have to add regular tap water (50-50 mixture).

Supafly

If i remember correctly, its distilled water.

mis3

This is what I thought but I called one MB service adviser and one MB technician (both my buddies at different MB dealerships) and they both told me they use regular water.

???

moondust

So your W209 is not 15 years old, and you haven't done 250k km.... what makes you think of changing it?

mis3

I like my CLK and I am thinking to do what's best for the car.

I am concerned that maybe the service book is wrong. Hard to believe that the coolant can last so long. Most car manufacturers recommend to change coolants every 100K KM.

Also, the automatic transmission fluid is supposed to be life-time but a lot of us change it anyway.

mis3

Maybe I should ask: Do you guys ever change the coolant in your w209?

ETN550

If you are questioning the factory recommendation then take a sample of coolant to a CAT dealership or any large semi truck dealer. They can get it lab tested and give you a full report on it's condition, addative depletion and project remaining life. Probably costs $25.00.

I worked for CAT and have done many oil and coolant analysis. Smart truckers rely on it as the cost to change 10 gallons of oil or antifreeze is expensive. Repairs are expensive too.

BTW, distilled water is best. Dealers do not use it because it is a hassle, but at least use soft water or water with low mineral content.

mis3

My car now has 150K KM and might as well change the coolant. I was told I needed a jug, about $20 CAN for the dealership.

I just called Mercedes Canada and they also confirmed that it's OK to use regular tap water to make the coolant solution. Strange???

redlaser

I would like to know where the taps are on the block and radiator so I can drain and then replace the coolant...can someone point me in the right direction please?

....

moondust

Welcome - but I would suggest that you ask in the W126 forum. We are CLK folks here