Heat issues and temperature fluctuation
#1
Heat issues and temperature fluctuation
I have some heat issues with my 01. A few weeks ago I did a complete coolant service on the truck I pulled the radiator, flushed it and degreased exterior. Flushed the block and heater core with water until everything ran clear. Installed all new hoses, new Cummins thermostat, new thermostat housing and filled with 50/50 mix with Preston Low Tox and distilled water. Have run the truck for about 500 miles and have some issues. The truck takes 20 to 25 minutes to truly warm up. I can watch the temp gauge get to operating temp 190 and then drop down to 175. This goes on for 5 or 6 cycles. Confirmed these readings with OBD scanner and live data through truck port. Once it gets to running temp the truck runs between 185-190. The heat blows warm not hot. On first and second position (low speed) of the fan the heat is warm. Third and and forth position (high speed) the air blows cold. I am not losing any antifreeze and do not smell anti freeze in the truck. Checked passenger side floor for leaks and it is dry. I am thinking the heat issues is a heater core but before I go through the aggravation of ripping the entire truck apart to do this I wanted to see if anyone had any other options. Also any reason why the fluctuation in temperature on the truck. Also I changed the oil after the coolant flush and it was pure oil. No water in the oil.
#7