I would not be concern as long as your weight fall within Toyota specifications. The 2014 highlander towing capacity meets or exceeds the SAE J2807 towing standards, which Toyota is one of the few companies that in 20014 used this very tough testing to confirm their towing capability. The one number you need to also look at is the CGVW (combined weight)
Most of us would never push our TV as hard as the SAE testing requirements. All of the manufactures have stated they would meet the SAE tow specifications, but they have been very slow to adopt because they will take a hit on there published towing capability. So my feeling is you are adding 15% margin in your numbers, which I think by meeting this standard the 15% has already been taken care of.
see a summary of the requirements:
http://www.automobilemag.com/feature...ss_sniff_test/
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