Beware Of Carriers Changing DOT Numbers. Are you working for a trucking company that has changed DOT numbers? If so, you may be part of a carrier that is scamming its way thru the system. Let me ask you this, for what reason should a carrier have to change their DOT number? Because they dont like that number? LOL, in fact there is no reason except the fact that they might have been told by the Department of Transportation to cease all operations.