Kingpin Settings

For those of us 53' van drivers that need to pay attention when sliding tandems, here is a quick reference for kingpin settings. We all know CA is the shortest at 40' kingpin to center of rear axle, but there are a few others that aren't much longer. Some have changed recently. I hope it helps.

Maximum Kingpin Settings per Rand McNally Atlas 2014

California- 40' kingpin to the center of rear axle
D.C.- 41’ kingpin to the center of tandems
Florida- 41' kingpin to the center of tandems
Illinois- 42' 6" kingpin to the center of rear axle
Maine- 43' kingpin to the center of rear axle (on designated routes only)
Michigan- 37’-41' kingpin to the center of tandems
Minnesota- 43’ kingpin to the center of tandems
Tennessee- 41’ kingpin to the center of tandems
Vermont- 41' kingpin to the center of rear axle
Virginia- 41’ kingpin to the center of tandems
West Virginia- 37' tractor rear axle to the trailer first axle
Wisconsin- 41' kingpin to the center of rear axle

 

Michigan- 37’-41' kingpin to the center of tandems

How can a 'maximum' use a 4 inch range?

 

So glad my stuff doesn't slide.

 

Different type trailers.

 

The best way to avoid worrying about bridge laws is to set up and load a 53' trailer for Calif. If the person loading the trailer knows what they are doing they can do this every time.

 

They have a maximum AND a minimum. The minimum is what started all this years ago when bridge engineers were concerned about too much [gross] weight being concentrated in a small area. The maximum is as much about maneuverability around corners and narrow streets as anything else with the introduction of 53+ foot trailers

 

It's "wheel base"....or "KP to center of tandems".
"Kingpin setback" is the distance from the KP to front of trailer.

"Kingpin setting" kinda confuses things. Not trying to be a ####....just saying.

 

Bridge law is MINIMUM not maximum.

King pin to tandem is MAXIMUM length.

It is possible to be legal on king pin length but not legal under bridge law. Example: a truck weighing 80,000 must have a length of 51' from center of steer axle to center of rear most axle. So a truck fully loaded with the tandems all the way forward would meet kingpin requirement (under 40' in California) but be only 50' total and be a violation to federal bridge law.

 

Thanks for the input. Yes, wheelbase is more accurate, measured kingpin to tandem axles. As a 53' van driver, I definitely don't have time to worry about the exact calculations of the bridge law; I just need to get weights, count pins, and move those axles till DOT is happy. For a quick reference, I like this list.

Unfortunately you don't have much control of how it is loaded, except to get your weight, slide your wheels, and then take the freight back and tell them to rework it if necessary. I have not had to do that yet luckily, but I got darn close with a 79,500 load in CA. Idiot distributor put a 1800 cat litter pallet on the back end of my trailer, and of course no scales for 27 miles. I measured the 40' to the middle of tandems instead of rear axle, which was 2 1/2 feet off. DOT pulled me in, said "move your tandems, but good luck with the weight." I broke the seal, broke down the pallet, and moved 1800 lbs of cat litter to the front end of the trailer where there was room on either side of a single pallet at the nose. It took two sweat-filled hours and caused a little damage to some cat litter bags and a few cases of SOS pads, but I scaled out with no citation, the lumpers rebuilt the pallet for me, and the customer was none the wiser when I put the seal in the back and just docked. Lesson learned.

 

If they really are concerned about the bridges out there they should make earthquakes illegal.