You will probably need to get an engine block heater for that old diesel in the winter.

Here's a '65 190D in action.

1965 Mercedes Benz 190D - YouTube.


You could get up to 35 mpg if you go easy on the car, and drive leisurely.

Which you would *HAVE* to @ just 55 hp. lol

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1991 560 SEC AMG, 199k <---- 300 hp 10:1 ECE euro HV ...

1995 E 420, 170k "The Red Plum" (sold)

2015 BMW 535i xdrive awd Stage 1 DINAN, 6k, <----364 hp

1967 Mercury Cougar, 49k

2013 Jaguar XF, 20k <----340 hp Supercharged, All Wheel Drive (sold)