Overheating in NW Mountains

My truck has started overheating in the hills. I have only ever noticed it happening in the Pacific Northwest, where I haven’t driven really until this winter, so I’m hoping that the brutal climbs there are just too much. But I haven’t noticed many other trucks sitting on the side of the road. Once I get off the hill, my temps come down quickly. I’m not using coolant. I’m driving a 2016 Peterbilt 587 with an MX-13. Fleet spec truck I bought from Prime. I’ve never really had a problem with any hills in the east, but I haven’t been over there recently to compare my truck’s current performance. Could there be something wrong with my cooling system if it can’t handle the hills like that?

 

Until you figure out what's wrong try pulling the hills a couple of gears lower than usual. Let that engine run free and easy and it might not heat at all.

 

I should probably mention that I have had a squealing belt for a while now. Yeah I know I’m douche bag and a rookie and I shouldn’t own a truck. I should roll my truck off a cliff and give all my money to a real trucker and go flip burgers. Thanks. Got that part.

Could a loose belt reduce cooling system performance?

 

Problem is, these hills are so steep and so long I have to go all the way down to fourth gear before she can handle them.

I read in another post about how keeping the RPM range high is good to keep air in the turbo and the fan spinning. But even in the lowest gears, the engine is getting bogged down.

Do you guys know these hills? California mount Shasta area, I 5, North into Portland, north into Tacoma, east over to Reno, etc?

 

Well the hills out west are alot longer pulls than out east... i always turn on the engine fan when pulling a hill... what are your temps ?...

 

How many speeds is ur transmission? If u said its a former prime truck then its not really geared for mountains like most fleet trucks.. I have a 13 speed and on the hills u mentioned i am down in 6th gear when loaded to 80k about 20-25 mph... keep the rpms at 1500 or higher when pulling

 

How many miles on the truck? Might just need the radiator washed out

 

Definitely make sure all the coolers up front are clear. If air can't flow through, they can't cool.

 

last time i was out west my truck ran hot in the hills to but here in Pa its fine

 

The engine shuts down at 240°. I’m trying not to let it get that hot before I shut down. I don’t have a manual fan switch.