My 84 300 D turbodiesel sees 4K RPM almost every day. I would do it more often and for longer periods of time during my commute, but it hogs gas with the AC on at that speed, and then there is often traffic as well. Cruises around 80 daily, though, which is slightly less than 4K. I've had it for 7 years, no engine problems (KOW).

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84 300D, 303K
71 MGBGT, ?K
96 GMC C1500, 115K