2005 HD 6.0 Diesel - 70K miles
In early Sept I found coolant level to be about a gallon low.
This past weekend I found it to be almost a gallon low again - 6 weeks / approx 1,700 miles
I have noticed white colored exhaust a few times in the past few weeks, particularly with the lower evening and morning air temps. Last night (approx 50 degrees) it blew white smoke for about first 3 - 4 miles and quit about the same time I noticed thermostat opened - don’t know if any connection.
Anyone experienced or heard of similar?