When it comes to getting your CDL training at no cost, there are tons of options out there, but you should know that none of them are in the sense that you get them for nothing.
CDL school offers always have some level of commitment required to the company sponsoring your paid CDL training. Think of it more like an NFL athlete who gets a signing bonus. If he ends up quitting on the team before the season starts, he loses the bonus. Most companies require you to work for them for a certain amount of time before they waive your tuition costs.