I don't know if any of you will know what I am talking about or not, but here goes. On virtually all semi's and all the semi's I work on, they have a hi/lo trans. You work your way up to 5th, then flip an air locker, and go back to where 1st is, but then it's 6th, and then 10th would be your highest gear. I have heard of a kit, or trans that you can buy so this kind of system is used on light trucks. Anyone that knows what I am talking about, or has any info, please help me.