My 84 300D runs at a needle-width below the 100*C mark, always, rain, shine, winter, summer at any speed above idle. Flushed the system, tried two different T-stats, even have a 180*C T-stat in it now, etc. no change! Always in the same spot. Concluded the factory gauge is not a precision instrument and more of a guide. Also run a 7psi cap to reduce cooling system stress. No issues. I guess she's healthy.... RT

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