Looked at a 2015 Toyota Tundra SR5 Double Cab 4.6L . Don't think its capable to tow a RV TT approx 30ft. I need a large Cab for my dogs. And want a truck to be able to tow a RV trailer and unhitch to go off with out the trailer. Any suggestions. What is the tow capacity of the SR5, The Tacoma, Tundra etc. Any suggestions?