You NEED to jack up the back end of the machine to adjust the chains, if the wheels can't turn freely the adjuster will only adjust the bottom of the chain as it is connected on the cogs at the top. Jack up the back end of the machine and then adjust the chainns and I bet you'll have years of trouble free use, I adjusted my chains 2 years ago when I got the thing and I have never had any trouble with them and it does a lot of heavy pulling and hauling and spinning tires.