There are plenty of options for fuel along the way including the rest stops on the NYS Thruway I87.
There is fuel available just off Airmont Rd exit in Suffern, but they tend to be high priced. After Suffern there is the first rest stop at Ramapo where it is very easy to fuel up with a trailer. After the Ramapo stop, the next places are at the I84 exit, then Plattekill Rest Stop and then New Paltz exit, Kinston exit and Saugerties exit.
I've been pulling a trailer to Lake George RV Park since 1981 and I've always found fuel at the Thruway exits without a problem.
2012 Ram 2500 Big Horn Crew Cab 8' box
5.7 Hemi, 4x4, 4.10
2015 Jayco Eagle 284BHBE