Your best bet in getting a full tank is the fuel station at Skukuza Rest Camp, 2.19 miles from the airport. This should be comfortably on your way back to catch your flight if you're coming from the direction of Kruger Park. Be sure to check your rental agreement before handing your keys in – if it's a fair fuel policy, you'll want to return the car with a full tank, otherwise, you might get overcharged for the refill. Search rental cars on KAYAK