In B scenario on the mission where you have to wreck all the Dim Sum stands in a limited time, if you get to the question mark (monster truck) before completing the mission you will be abale to find the Monster Truck. To get to the truck, go down the street a bit (where the question mark is) and there is a wooden jump.Goabout 65-80 mph jump straight off of it. You won't be able to see much because of the explosions but you will land on a platform that will lead to a showroom type area where the mighty monster truck lies. run into it and quickly complete the mission to get it.