I have an 01 HO, 6 speed, with a FASS platinum lift pump, otherwise stock. Recently it has begun heating up on grades, especially while pulling(duh). Today I had to pull over and let it cool down multople times while pulling up 6% grades with a load of hay, about 15K total trailer weight. I could not get 2 miles uphill without almost pegging my temp guage. Pull over or get to the top and it drops right down. Even on relatively flat ground I'm running 10-15 degrees hot, or 200 degrees +. I'm wondering if it is simply the fan clutch? Seems likely after reading other posts, but they are usually talking automatics. Any thoughts??
Thanks in advance,
JC
Thanks in advance,
JC