Patricia, I notice your Rav4 is a 4-cylinder version. If it's a 2005 or older, that means its horsepower is very similar to my 4-cylinder Camry. I find the Camry marginal for towing my Compact Jr, which is probably lighter than a 13' Burro
, and certainly has less frontage area. This is at sea level, but we do have some noticeable grades here.
One thing I find amusing is how well the trailer acts as a drogue chute -- if I'm going down a 6% grade the car and trailer combination hits about 52mph while coasting. That same car going down that same grade but without the trailer will coast far faster than I want to go -- I don't like to let it go over 70mph and so I have to use the brakes
to keep the speed less than that.
Going up the same grade with the trailer I have the choice of going 48-50mph but at about 4000rpm, or 42mph at a much more reasonable 3000rpm. If it's a multilane highway I choose the slower speed, but if it's a 2-lane road with traffic stacking up behind me it 4000rpm all the way to the next turnout or passing lane. Sometimes I'm lucky and get stuck behind a slow-moving truck -- then it's his fault and not mine! I just make sure to allow room for people to pass me without having to pass the truck as well, and I pull over into the pullout with the truck to let everyone by both of us.