our 2010 27sc is rated at around 3500lbs GVWR. A load range C tire should be around 1800lbs - which is 3600 total, not counting tongue weight (at least 500 lbs.) which would put only 3000 lbs on your tires, will within their design spec.
In other words a "c" tire is more than up to the job. Unless you overload your trailer - and then tires may be the last of your worries.
2013 Coachmen Freedom Express 320BHDS pulled by a 2005 F250 King Ranch CC
A rainy day camping is better than a sunny day at work.