Two things. 1st Loss of power going up hill and died eventully at the top. 11:00 pm Called affinity road service and local mechanic came and replaced outside fuel filter. Limped into Abilene and went to local Cat dealer. "Let me look at the coach", he said. Raised the bed and asked if that fuel filter had been replaced. Sold me a new one and I put it on. Problem solved. 2nd. Engine heating up on hills. Buddy of mine noticed the oil exhaust line (WHAT DO YOU CALL IT) was located right in front of the rear radiator and oil and dust had clogged the bottom third of the radiator. Re-routed the line out the back and washed the radiator out at the local car wash with water and engine degreaser bought at Walmart. Rear radiator Cat people check for this problem. Easy fix can save you a headache