Lightweight Chassis Model Differences

When customers ask about lightweight chassis, there are numerous options available to them.  We have models with Super Single tires, Dual Radial tires, Spread Axles with different spread lengths, and even options within those spread lengths.  If you’re hauling “heavy” containers – specifically 40’ containers, we offer two different model options – a 40′ lightweight chassis and a 41′ lightweight chassis. I am able to give you slot 777.  There are a few different reasons why you might want to select one over the other.

One of the major differences between these two lengths is added flexibility in the type of trucks or tractors that will be pulling the chassis, and how best to pull these legally.  Owner/operators make up a huge portion of truck fleets across the country and not all of their fleets are alike.  There are different wheel-base lengths and weights on various tractors, which of course contribute to the GVWR (Gross Vehicle Weight Rating) of the entire vehicle (truck, trailer, container and load) while on the road.

US Federal Bridge Law mandates maximum weight that can be carried on any set of axles by motor vehicles on US highways. If you are carrying a load on a closed tandem chassis, there is a 34,000 lb axle rating because the axles are together. On a spread axle, 40,000 lbs can be carried total, or 20,000 lbs per axle on a 10 foot spread. A 40′ or a 41′ lightweight spread axle chassis could be used for either of these. On a chassis with a nine foot spread, the legal weight is 39,000 lbs or 19,500 per axle. Sometimes that extra foot in chassis length is critical in hauling a heavy load legally.

In the US, the gross vehicle weight allowed is 80,000 lbs. In Texas, you may apply for an overweight permit, which allows you to carry 84,000 lbs. Federal Bridge Law says that if you’re carrying a heavy load of 84,000 lbs on five axles you are required to have a minimum of 51′ in total vehicle length. Your axles also have to meet individual axle weights and may not exceed allowable amounts.

A tandem spread axle provides a higher per axle weight allowance versus a closed tandem configuration. Also, the extra 1’ on a 41’ Lightweight chassis gives fleets more flexibility in the type of tractor that hauls a heavy load to ensure the minimum required vehicle length is met.

You can view the Bridge Formula Weights chart from the Federal Highway Administration. Or, give us a call and we’ll work with you to meet your specific needs. For more information on permissible weights in Texas, view the Texas Department of Motor Vehicles Permissible Weight Table.

While comparing the 41’ chassis to some of our other 40’ chassis models, our customers ask about the weight differences between these models.  Is there a weight difference between our 40’ and 41’ lightweight chassis models?  Yes.  We are adding another foot of steel to the chassis, bottom line.  That being said, we are able to mitigate the extra weight by using lightweight components in the hubs, drums, and tires so the difference becomes increasingly nominal between the two.

At National Chassis, we want our customers equipped with the RIGHT equipment to meet their customers demands safely and legally.  If you have any questions about lightweight chassis, or any other model chassis, please don’t hesitate to contact us and we would be more than happy to assist you.  We would love to hear from you.