Do you mean a 2015 Jayco Eagle 338RETS? Jayco has the loaded weight of that unit at 10,950lbs. 15% of that would be 1,575lbs tongue weight.
I believe the figure you provided for the van (9,500lbs) would be the maximum for the fully loaded trailer PLUS what (and who) you have IN the van.
Seems like much too much.
Sherm & Terry w/rescues Steve (std Poodle) & Eydie (min Schnauzer)
2015 Jay Flight 27RLS (Camped: 102 nights 2015, 90 nights 2016)
2006 Ford F350 6.0 PSD, Lariat, 4WD, CC, LB, SRW, auto., Camper pkg.