If your towing unit GVWR is under 12,000#, and your trailer is tagged at 14,000# you don't need a CDL, but...only if you NEVER exceed GCVW of 26,001# (including cargo + vehicles + dirt clods)
If total combined GVWR is over 26001# you need a CDL
if trailer GVWR tag is over 10,000# AND GCVW is over 26,001# you need a class A cdl
The Federal standard requires States to issue a CDL to drivers according to the following license classifications:
Class A -- Any combination of vehicles with a GVWR of 26,001 or more pounds provided the GVWR of the vehicle(s) being towed is in excess of 10,000 pounds.
Class B -- Any single vehicle with a GVWR of 26,001 or more pounds, or any such vehicle towing a vehicle not in excess of 10,000 pounds GVWR.
Class C -- Any single vehicle, or combination of vehicles, that does not meet the definition of Class A or Class B, but is either designed to transport 16 or more passengers, including the driver, or is placarded for hazardous materials.
full CDL discussion over on Heavy Equip forum
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