NYS is R endorsement for class 5 license if you are over 26,001 GVWR total or over 40ft. A class A or B CDL superceeds this endorsement which I have a B with air CDL. PITA to get and maintain a CDL today, but I get a discount on ins so I keep it.
R endorsement is obtained through a road test in your RV or TV and trailer setup. No written test.
As long as you are leagal within the state you hold your license you are covered.
CDL's are now federal.
2014 375 BHFS Eagle Premier
2014 Ram 3500 Longhorn DRW CC
6.7 CTD, Aisin, 4.10's