Here are some before and after temp numbers, not much of a test but interesting anyway.
Before numbers:
I just went on a quick 3 mile round trip to load my dump trailer, slow 1st gear road and let it idle while I unloaded. I checked temps on the system. The pump was 135*, hydro boost 135, lines 105 and the gear box was 114
After numbers:
Just hauled 3 loads of cinders, 20 mile round trip, 14 miles of slow county road pavement and 6 miles of slower dirt, ambient temps from 70-90, truck ECT was an average of 185. On my middle load with AC on, truck idling, the pump was 109, hydro 109, box 106, lines 105 and cooler 88. I tested the lines where the rubber meets the metal, about 6-8" from the hydro, I didn't test the lines at the box.
This is with 285/75x16 tires, stock aluminum wheels. This size has been on the truck since I bought it, in '03 with 34k miles, it now has 320k. The front end is all original, other than the brakes and shocks