Jamie,
Nope, while the engine isn't the biggest thing out there it should be able
to do the job just fine in the flat country. And if you're not in a big
hurry you will eventually make it to the top of the hill.
Make sure you have a good, properly installed weight distributing hitch to
put them together. If your Sub. already has a receiver on the back for the
hitch, it should also have the towing electrical package. This makes adding
a brake controller easy, you knew about them right?
Charlie