1995 - E320
225 K Km. Own for 3 years

Replaced Water pump, tensioner, AC compressor, thermostat, fuel lines and couple of unrelated things around 2010 - 170 K Km.
Normal service schedule, coolant was replaced a year ago.

No issues whatsoever, so far.

Working temp is around 90-95 degrees, closer to a 100 in a traffic, but never over 100, even in 34-37 C(99 F) ambient temp. Ac was not a factor

Right now I do observe a change. Car was parked for 12 days.
Slightly lower temps in the highway speed - around 80-85.
With AC temp is higher and
in the traffic with AC can reach 110.
Pair of Aux fans are kicked in properly on AC on event.

Any ideas? Thanks,
PS> Radiator is still factory original

If its not overheating while driving, its probably time the radiator needs to be replaced along with cleaning and removing any debris, leaves, dirt from the fan shroud and condenser.
Plus, being in Canada, you shouldn't even be seeing 100C if the system is working right let alone 110C.

I don't even reach 110C in 117F ambient heat in traffic...we can quite literally cook a steak on the street here in the summer...

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2016 Monsoon Gray Audi Allroad - 21k
2008 Black Mercedes E350 4Matic Sport - 131k
2014 Jeep Wranger Unlimited Sahara - 62k
2003 Gray Mercedes ML350 - 122k

Your instrument cluster needs a more reliable ground connection.

__________________
600SEL '91
300E 4Matic '88
240D '83
280SE '77
350SE '73
The most complex systems can fail in the simplest way.
Contra verbosus noli contendere verbis, sermo datur cunctis, animi sapientia paucis.

i don't believe in the lord! He's never bought me a Mercedes Benz.

I think there are two speeds to the fan. One signal generated my the ac system, the higher speed from an engine temp sensor. Do they both work? Jump the sensors and see what happens. good luck

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71 220D 169K wrecked
83 240D 118K sweet 4 speed
91 350SDL (one of the 60% good engines) 156K
84 300d (loaner to my sister) 189K
79 300SD (partswagen)
86 420SEL partswagen
70 220d (partswagen)
68 280s GASSER!!! under construction now
85 300sd 310K miles winter beater car retired
93 300d 2.5 turbo 168K wife's car
83 280SL euro 5 speed 155K
69 250S newest project 54K

Decided about coolant flush and thermostat replacement.

Going to put 79 degree BEHR, despite this is not factory specs.
Reason - this is 3 seasons car.
I do not drive this car below freezing, summer only


Next - will look into radiator replacement

Question which one is better - Behr or Nissens ?

Recommend staying with an 87 degree thermostat because the engine is designed to operate at that temperature. As for the radiator I would go with the Behr, but either one is fine from what I have read over the years. Verify that the radiator is the upgraded version with the metal-reinforced upper hose connection.

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Fred Hoelzle