Gets hot

[dirttracker0]

Have the 300 cummins in a 2000 fleetwood discovery.Temp climbs when going up hills seems to cool back down when it gets back on leavel ground.Had the dash air fixed thats when all it started doing this checked all fluids there fine.It runs hotter now than it did before i had air fixed the temp never used to move past a quater on the guage now it runs closer to 3/8 and above.have not pulled big hills yet but going to soon any sugestions.

[Caemlyn]

dirttracker0,

pretty normal behavior, drive to the tach - keep engine running at between 1600-1900 rpm and down shift manually to keep it there. Also check your radiator for any blockage and clean at least yearly. I have a Cummins ISB which runs quite warm when climbing grades, but if I keep the rpms up it never overheats and will cool fairly quickly once the load is reduced. My will climb to 200-205 degrees going over Donner Summit on I-80 at 55 MPH, well within Cummin's operational tolerance.