The owners book calls for 10w40 that’s what I use.
The owners book say’s change the oil every 5000 miles, that’s what I do.

When we first got the car I had the technician sort out the vacuum system. Only problem was the trunk lock. That leak caused the car not to shut off. It literally took him five minutes.

I also had the cooling system flushed, it was nasty.

I got lucky, the car has been extraordinarily well-maintained.

If the car has the original paint on it, be sure to look at the tricks to bring it back to life. It’s not easy.

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1981 240D Four on the floor, Orient Red over Parchment, bought with 154,000 but it's a daily driver and up to 180,000 miles, mostly original paint and all original interior.