Re: Mercedes benz 450 hp problems
 

Showhauler with stacker at 65 to 70 I get 8.5 to 9. Had one time I had fan running all the time on hot day. I was told the use of the incab AC was causing the temp to rise so fast.
I did replace a sensor and when I opened the line air bubble came out and has been fine since. May have been giving a false temp signal? False pressure?

Re: Mercedes benz 450 hp problems
 

Look at the turbulance you create with your rig. I have a wing on both my motor homes. Worth 20% fuel economy and abut 10 degrees operating temp. Notice when you go through the rain how much turbulance you create, or on a road with a dusty side, see how much dust you create on the curb side. You should try to get the wind off the front of the trailer and over the trailer smoothly. Just look at the big trucks on the highway. Notice how much effort is made to make it go through the air smoothly.