GVWR of the Thor Siesta is 11030. 88 gallons water about 734 pounds. 26 gallons diesel about 182 pounds. Figure about 1600 pounds cargo/persons headroom.
If the truck is empty, it SHOULD weigh about 8500 pounds. HOWEVER, a similar older model on a Sprinter chassis with the same GVWR claims in an RV forum...
"2009 (2008 chassis) Winnebago View (for sale since purchase of a Citation Sprinter SR). GVWR is 11030: Limits are 4410 Front, 7720 Rear with a GCWR of 15,250 (max tongue weight of 500) the per the specs in the sales brochure."
This person went on to claim he weighed the truck with just him in it, full fuel and LPG and water, and with just that ONE PERSON and ZERO cargo in the RV, it was 100 pounds over GVWR on a CAT scale at a Love's.
So if the front axle load is 4410 and the person isn't in it, that's quite a load for that wheel lift.