The spread axle tandem truck is a common truck combination that many trucking companies use. The benefit of having spread tandems on a trailer is that the trailer axles are counted as two single axles and therefore have a load capacity of 40,000 lbs, as opposed to the 34,000 lbs capacity available for regular tandem axles. The drawback of using this combination is that if you use spread tandems on a trailer over 48’, then kingpin to rear axle restrictions apply in many states. Because of this, spread tandems are only usually seen on trailers 48’ in length, which do not have to comply with the KPRA restrictions. Common uses of spread tandems are with flatbed carriers, who want more flexibility when scaling out their load, and are more willing to sacrifice some deck space for better axle weights. Another common use is with fruit and vegetable haulers in California, who usually weight out before they cube out, and using 48’ trailer allows them to disregard California’s strict kingpin-to-rear axle restrictions on trailers 48’ to 53’ in length. Severe restrictions on axle weights in western Canada mean that this combination is very rarely seen there.
