I've driven my 240D from Carson City down to Port Hueneme, CA (near Oxnard) and back. On the steeper grades, particularly at high elevations, it wouldn't do the speed limit, but it made it without any mechanical problems. I'd find the same trip more enjoyable in my turbo 300, but the 240 can handle it as long as you don't mind going slow.

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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.