Happy Trucks is an online game at 43g.Com. You can play Happy Trucks in your browser for free.Happy Trucks is a filling puzzle game. Your job is to fill up the trucks with liquid. Do that in all 30 levels. For each level there is a different truck, so you need to estimate how much fluid will fit in that truck. You should not overfill the truck, nor should it be half empty. If you make a mistake in the assessment you will start playing that level again. Very interesting game that you will enjoy playing.