I know that labor on replacing items on a V8 (400E) has to be more $$ because of the lack of room in the engine compartment, but I'm not convinced they are that much more expensive than a 300E.

Why?

It seems all six cylinder W124's (300E's / E320's) have trouble with headgaskets failing, a big ticket item to replace ($1,200 - $1,800).

The V8's never have head gasket problems.

Last, there is almost no mileage penalty with the V8. The difference in mpg in only 1 - 2 mpg in both city / highway fuel economy compared the to the sixes.

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Paul S.

2001 E430, Bourdeaux Red, Oyster interior.
79,200 miles.

1973 280SE 4.5, 170,000 miles. 568 Signal Red, Black MB Tex. "The Red Baron".