Quote Originally Posted by yebo
does not apply anymore to vehicles with electric motor driven auxilliary and radiator fans.
It still applies pa din kasi the higher the rpm(the more speed you have), the more splash created inside the engine bay thus entry of more water inside engine(air intake, spark plugs etc.)
Usually, a 1500rpm will suffice than say a 2000 to 2500rpm. But I guess it depends on a case to case basis especially if its incline etal.