This money racket is an issue that has and may bite many more rookies in the butt. Those who pull dry vans, reefers, and most flats and tankers need not be concerned. However, those who pull dump trailers, containers, and the occasional short flatbed would do well to mind their axle spacings. I've gotten a couple large tickets under the bridge law. This is a federal thing, so it applies in every state. There is more to it than the max 41' from kingpin to center of trailer tandem rule on 53's although that one is important to keep in mind. In order to legally gross 80k with the standard axle weights of 12k, 34k, and 34k on 5-axle combo, you must not only measure at least 36' from frt drv axle to r. trlr axle, you must also measure at least 51' from str axle to r. trlr axle. Where they can get you is if for ex. you're pulling a 30' dump trlr and you only have 28' from your frt drv to your r. trlr axle, your max. allowed tandem weights are reduced to approx. 30k apiece. You're still allowed 12k at the str(although every state has a different standard for this. MD happens to go by tire rating.FYI). Your max allowed gross weight is now reduced to about 72k. Bridge formula fines are hefty. You can also be over gross but not over axle anywhere. This is possible on spread axle trailers. Most flatbeds come that way now. You can scale 40k legally on your trailer axles if they are 10' apart. All of this can be found in Rand McNally's Motor Carrier Road Atlas.