Dear friends:

I have heard and read that some Mercedes 240D (years 1979 - 1981) can get as high as 40+ mpg (highway) even with AUTO transmission while other Mercedes 240D (same years) can only get about ~ 24-27 mpg (high way) even with MANUAL or AUTO transmission. Why is there such a large discrepancy in mpg?

It also seems that 240D can come with either 4 or 5 cylinders. Why the model name does not have some extra letter to differentiate between 4 and 5 cylinder ones?

In your treasured opinions, what parts should be recommended to be replaced in a 1981 Mercedes 240D (4 cylinders and manual transmission) when it reaches about 230K miles?

Thank you very much for all your precious help.

Best regards,

Eric