"Yoda' '08 4Runner

[Jake]

Also, towing is fun, but I'm not sure if the trailer I was using to haul some furniture had touchy brakes or what, but the module in the 4Runner seemed to go from 0 to 100% braking, locking up the trailer I was using. I don't have a trailer (yet) but just interested if anyone knows ways to adjust it. I'm guessing my load was too light which was probably the bigger factor. I can't imagine people tow much with these things, 7000lbs just doesn't seem like that much considering this is built on a truck platform.

If the trailer was light, you need to adjust how much force the brake controller exerts on the trailer brakes. There should be some +/- buttons that let you adjust it, as well as a slider that will give you 100% brakes when applied (for emergency use, normally). The idea is to get up to about 20 mph, pull that slider, and have the trailer almost lock the wheels but back it down a click or two. That's a good starting point, then adjust as necessary based on load/weight.

7k lbs is a LOT for a 4Runner. Yes, it's based on the Tacoma and has a real frame, but weight is also dependent on wheelbase, braking ability, and weight of tow vehicle. My Range Rover is rated for 7700 and has another ~5" of wheelbase on the 4Runner, which will go a long way with stability. 

People have used 4Runners to pull smaller cars (Civics, Integras, E30s) on open trailers but I would be very cautious beyond that - moreso due to the wheelbase than anything else.