I've driven my 240D over the Sierra Nevadas many times. There are two passes over 8,000 ft between Carson and San Diego, and it makes it just fine, as long as 40 mph classifies as fine.

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Whoever said there's nothing more expensive than a cheap Mercedes never had a cheap Jaguar.

83 300D Turbo with manual conversion, early W126 vented front rotors and H4 headlights 400,xxx miles
08 Suzuki GSX-R600 M4 Slip-on 22,xxx miles
88 Jaguar XJS V12 94,xxx miles. Work in progress.