Stay close to the numbers and you should be OK.
With respect to the tow capacity, using the Winnebago View 2011 specs. If the View is loaded to the gills, its GVWR is 11,030 lbs. The maximum weight with the toad is 15,250 lbs. This leaves only 4,220 lbs for the toad, even though there is a 5,000 lb hitch. Even if you were over by 500 lbs I would still do it.
One thing that Winnebago does not list in their specs is the CCC, the cargo carrying capacity. They also don't list the CW, curb weight of the View.
BUT, you will need to load the View up with what you want to take, then get it weighed (4 corners). From this you will be able to make sure the tire pressures are correct and the weight is correctly distributed fore and aft, and side to side. Based on this you might want to make some adjustments.
The Sprinter is a good chassis and the diesel engine will help on the hills. Even though it only has 188 hp, its the 325 lb-ft of torque that make the difference.
2002 35R Southwind, W22 8.1L Vortec UltraPower, 19.5' wheels
Toad: Wrangler, lifted and on 35" tires