The 5.0 liter engine is the same on all of the years, I think, except the last year or two of the R129 model run, where they switched to the newer engine that the E-classes use that have three valves per cylinder and two spark plugs.

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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".