Here's a link to the product brochure. Unfortunately it doesn't mention anything about an installed receiver or capacity.
http://www.gulfstreamcoach.com/towab...%20Edition.pdf
I'd think a 5,000 lb trailer might be more than the RV can handle safely. With a Class C, you have a long distance between the rear wheels and the rear bumper. Adding a very heavy trailer that far back can seriously effect handling. Check carefully for the weight ratings. Required to be posted near driver's seat, also often found on a sheet pasted inside a cabinet or closet inside.
You want to look for the RV's
GVWR (Gross Vehicle Weight Rating) means the maximum allowable weight of the fully loaded vehicle, including liquids, passengers, cargo and the
tongue weight of any towed vehicle. GAWR (Gross Axle Weight Rating) is the maximum allowable weight each axle assembly is designed to carry, as measured at the tires.
GCWR (Gross Combination Weight Rating) That's the total weight of the loaded RV and trailer together. The term
NCC (Net Carrying Capacity) was used up to the year 2000, starting Sept. 2000 the term is now
CCC (Cargo Carrying Capacity) means
GVWR minus the following: UVW, full fresh (potable) water weight (including that for the water heater) full LP gas weight, and
SCWR (Sleeping Capacity Weight Rating - Sleeping capacity X 154 lbs per bed)
To have 5,000 lbs tow capacity in a Class C RV is rare, the RV itself is usually pretty close to the chassis and axle limits. To tow 5,000 lbs, you'd need a receiver hitch of at least a Class III rating, (6,000 lbs, 600 lbs tongue rating)