I think I bought the Slime at a local auto store or big box store. I purchased four 1 pint bottles. I put one bottle in each front tire and still have two left. I will not load my tires. Loading the tires would be pointless, for me at least, because I want the machine as light as possible as it is my primary lawn mower. I don't have any major traction issues with my turf tires. For loader work on loose material, loading the fronts would accomplish nothing as they are the pivot point. Loading the rears would add a few pounds, but I don't want to do that as it could cause undue stress on the center joint. I like the unit just the way it is, so the slime was the way to go for me. /forums/images/graemlins/smile.gif