Hello everyone, just a quick update on how I fixed my2006 Tioga 24D on a 2005 GMC 3500 chassis from running to hot on long grades. I found that my problem was caused by several things related to my cooling system. Those 3 items were the fan clutch, thermostat and radiator cab. The radiator cap wasn’t able to build enough cooling system pressure (less than 5 psi), the thermostat was a little late in its opening temperature (195 degrees versus its 187 degree rating) and I think the biggest problem area was, the fan clutch never engaged even at 237 degree water temp. I installed a new 180 degree thermostat, a new 15lb radiator cap and a new Hayden severe duty fan clutch. The total cost of parts was $120.
On my test drive earlier today, pulling my same boat up the Cajon Pass with the dash A/C on max and generous amounts of throttle angle to work it a hard as possible, the highest temp on my Scangauge (and the dash gauge) was 207 degrees. The fan clutch only fully engaged once for 40 to 50 seconds during the whole trip and the temp came right back to 200 degrees while I was still climbing the grade and then the fan clutch disengaged. The normal operating temp on anything but long grades is the same 197 to 198 degrees as it was before.
Now I feel completely comfortable that anyone could hop in my motorhome and drive it even in Death Valley in August without it running excessively hot. So for anyone who is tolerating a motorhome that’s running hot, it’s not normal and it can be fixed. I hope this information is useful to someone out there in internet land.
By the way, I stopped by the truck scales on my way home to see what my motorhome and boat weigh. My 2006 Tioga 24D full of gas and water and me in the drivers seat, but no food or other passengers weighed in at 10,920 lbs (3320 lbs on the front axle and 7,600 lbs on the rear axle). My boat weighed in at 3,100 lbs. That brings my grand total weight minus food and 3 passengers to 14,020 lbs, well within spec.
That’s it for now.
