Hello, I am looking for a new engine for a 1997 W140 S420. Would the 4.2 engine from other models such as W124 and W210 fit? How about the 5.0 litre version from an S500 or any other model with that engine? What would need to be done to fit it? Thanks.

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1982 280SL - Petrol Green
1994 E420 - Brilliant Silver
1995 E320 wagon - Smoke Silver

The 1996-99 S420 engine OR the 1997 E420 would be the only direct swap.

The 1996-99 S500 will also "fit".

Earlier engines would require disassembly & replacement of internal engine parts including
camshaft gears. Also many other parts would have to be swapped.

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