I have been using my new BX1500 to plow my drive the last two days and even after plugging in the engine heater for 7 hours then running it for a couple of hours while plowing the temp guage still sits at the beginning of the scale or just barely into the scale (above the line). Is this normal for a diesel? Ambient temps have been around 10 F to 15 F above. If that isn't normal, are there any suggestions on raising the temp? Is it advisable to install a higher temperature rating thermostat in a diesel? My HST seems to make a lot of groaning noises especially in reverse and I didn't really notice these sounds a few weeks ago when temps were still around 40 above or more; could the low engine temps be indicative of low HST fluid temps and be creating problems of poor fluid viscosity for the HST? Any suggestions would be appreciate. Thanks for your time.