Here is the maximum weights and lengths in CA in regards to RV's pulling a trailer with a standard issue Class C license. I believe this to be correct, if it is incorrect, please correct it below.
1. Max length and weight of coach? 26k lbs, 40' and under for 2 axle, 6k lbs or less for 3 axle, (sounds like they don't want you to drive a 3 axle..?)
My question is "Why would there be a limit of 6k for a 3 axle coach, but you can drive 26k or less for a 2 axle coach? That would be like a 3 axle 6 cylinder Toyota truck type Class C."
2. Max length and weight of trailer? no length limit (which I find hard to believe), 10k GVWR including a tow dolley, if used.
Found in DMV book titled "Recreational Vehicles and Trailers Handbook".
May vary from may vary from county to county also?
you may have to cut and paste the link below
http://www.dmv.ca.gov/pubs/dl648/dl648.pdf
Quoted from "Recreational Vehicles and Trailers Handbook" (DMV book) list excludes non commercial Class B and A licenses.
you may drive:
any 2 axle vehicle with a GVWR of 26k or less.
any 3 axle vehicle weighing 6k gross or less.
any housecar, 40' and under or less.
you may tow:
a single vehicle with a GVWR of 10k or less, including a tow dolley, if used.