When I was at Ford we had different cooling tests for European models. I tested some US spec vehicles to the European tests.

The European test included a low speed climb. The ambient temperature was lower (I think it was 30°C or 86°F.) The grade was 12%. US tests are at 8%. The speed was 30 kph (18.6 MPH.) We ran this speed for an hour as I remember. I probably have the spelling wrong, it was to simulate an actual climb called Grossglockner.