Ram 1500 trucks generally seem to have lower payload ratings than any other brand.
Personally I have no use for a 1500 truck. I have a 2500 Suburban to tow my 6,500 pound boat and I use a dually to tow my flatbed with excavation equipment up to about 13,000 pounds. If you want a truck to tow that trailer you will be far better equipped with a 2500 series truck of any brand. Don't fall into the trap of thinking that automatically means getting a diesel. There are plenty of gas powered 2500 trucks out there.