I have a single axle frieghtliner sport chassis, it is registered as a heavy duty pickup class 5. that keeps my weight limits good for pulling. I have a class a CDL exempt which is all that is required in Texas. Look at your Gross gvwr and figure out if you are over 26,001 pounds. I also carry commercial insurance on the truck itself, makes it about the same as the 1-ton pick up I had. Air brakes will require one of the CDL on your license. but it sounds like your covered unless your wife is driving. also check your insurance coverage to make sure you are covered for the wieght. Some insurance companies will fail to pay a claim if you weigh more than the limits of your insurance , or are over gross weight limits. States are getting more particular with trucks and fifth wheel RV registrations. Enjoy the 359 Peterbuilt does have a narrow cab. make sure you can pull the hood up to check engine compartment.
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