I wouldn't bother with a used radiator unless this was some rare or unusual collector car where preserving originality was important. A used radiator should be professionally cleaned and pressure tested, which negates any cost savings of buying used. Yes newish radiators have plastic end tanks that become brittle with age and heat cycling. IMO its best to consider the radiator a wear item, just like the water pump, and replace both every 120k miles. I've used Nissens brand radiators in several different cars including my '98 E300, and have not had any problems with them.

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1998 E300 turbodiesel

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