askthemercedesmechanic.com

Hi James,

I have a 1993 E420 with 105k miles on it, how often should I flush and fill the radiator/cooling system.

Your radiator and engine cooling system should be flushed and filled at least every two years, fresh water is the best allowed to run thru the cooling system until it is clear. Avoid most chemical products as they are hard on the aluminum heads. Also make sure to use an approved Mercedes coolant, like that from the dealer or Zerex G05, other wise you run the risk of internal corrision to the radiator and engine.

Any more frequent changes of fluids will certainlly not hurt anything. When you are changing the coolant, make sure the hoses are in good condition and not cracked or worn. Make sure to check the heater hoses as well as these are the ones that normally fail.

Good luck with your repair!

James

Hi,

 I have a 1990 Mercedes Benz 260E, with 125k miles on it, would it be ok to switch to Mobil 1 Synthentic ATF?

Hello,

 As long as the Mobil 1 Synthentic ATF fluid you are looking at is on that meets Dextron Type II, or Dextron Type III, your should be okay. One thing to keep in mind is steering clear of a fluid that contains any sort of friction additive, as these can changes the working pressures inside the transmission. Additionally a synthetic fluid will do more to protect mechanical parts, which in your transmission should not be much of an issue. The point of failure is normally as friction points, like the bands, and clutches and these will wear with time.  In short it is probably not worth the extra money to change to a synthetic fluid in this car, but I cannot see the fluid doing any damage as long as it is the proper type and does not contain any additives.

 Good Luck with your Car and Repair!

 James

W124 was the internal chassis-designation for the 1986 to 1995 version of the Mercedes-Benz E-Class. The W124 models replaced the W123 models after 1985 and were superseded by the W210 E-Class after 1995.

Chassis code Years Model Engine Body style
124.026 1987–1989 260E 2.6 L M103 I6 sedan
1990–1992 300E 2.6 sedan
124.028 1993 300E 2.8 2.8 L M104 I6 sedan
124.023 1984-1992 230E 2.3 2.3 L M102 I4 sedan
124.030 1986–1992 300E 3.0 L M103 I6 sedan
124.032 1993–1995 300E 3.2 L M104 I6 sedan
1993–1995 E320 sedan
124.034 1992–1995 400E 4.2 L M119 V8 sedan
1992–1995 E420 sedan
124.036 1992–1993 500E 5.0 L M119 V8 sedan
1994–1995 E500 sedan
124.050 1988–1989 300CE 3.0 L M103 I6 coupé
124.051 1990–1993 300CE 3.2 L M104 I6 coupé
124.052 1994–1995 300CE/E320 coupé
124.066 1993–1995 300CE/E320 coupé
124.090 1988–1989 300TE 3.0 L M103 I6 station wagon
124.092 1993 300TE/E320 3.2 L M104 I6 station wagon
124.120 1986–1989 200D 2.0 L OM601 Diesel I4 sedan
124.128 1990–1993 300D 2.5 2.5 L OM602 Diesel I5 sedan
124.131 1994-1995 E300 Diesel 3.0 L OM606 Diesel I6 sedan
124.133 1987 300D 3.0 L OM603 turbo/NA Diesel I6 sedan
124.193 1987 300TD station wagon
124.230 1990–1993 300E 4MATIC 3.0 L M103 I6 sedan
124.290 1990–1993 300TE 4MATIC station wagon