My #14 has been fine so far. Don't worry too much about it.

Check the vacuum pump.

Take the intake manifold off and replace the glow plugs, and clean as much crap out of the runners as possible. Disable EGR.

Consider sending injectors to Greazzer while they are easy to get at.

Upgrade to the plastic fan and new clutch.

Replace the temperature sensor with the lower temp version -- red top IIRC.

Thermostat. It's somewhat of a PITA in the car with small hands, next to impossible with larger hands, I imagine.

REPLACE THAT @&$% FLEX JOINT IN THE SPLIT MANIFOLD! Mine is leaking and I dread the job of getting that apart with the engine in the car...

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Garage:

2017 Chevy Colorado Diesel (nanny state emissions)
2005 Volvo S40 T5 AWD, 77k
1987 Mercedes-Benz 300D turbodiesel, 4 sp auto, 156k - 28.7 mpg
1996 Tracker 4x4, 2 door, 16v, 3 sp auto. 113k - 28.6 mpg

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