For some reason when I'm going uphill, over a mountain pass my A/C cut off. I turn the fan on high and can hear it running but nothing comes out of the vents. It's fine on the flat freeway and and everywhere else. Only when the motor is pulling hard to go uphill.
Has anyone ever had this problem before??? My A/C belt is new. I hope I can get this resolved as it's stinking hot here and I need A/C after work!! This is a 2006- 2500

 

vacuum leak.

check hoses, vacuum tank, check-valve etc.