I have a 2013 Dual cab Prerunner TRD Sport with tow package and automatic transmission.
I do not tow regularly, just a couple times a year at most. Just finished moving all of my furniture and stuff 320 miles. I pulled a U-Haul 6'x12' enclosed trailer. Which is the biggest they offer. The trailer was full, and so was the bed of the truck. I will include pics of the final load. (the pics were taken after the trip, before unloading)
The trip included a couple short but steep hills, and I had no issue with pulling the weight. Though I could definitely feel it behind me.
The back up camera is a dream to help trailer hookup, especially if your assistant is not very good at giving direction. I was able to back up for hookup unaided.
I had almost no sway during the trip, What minor sway I did have, which I would say was more of a very slight few inch wobble than actual sway, was caused by occasional wind gusts and uneven road surfaces near construction/road work. The Tacoma has a sway control built in (or at least the window sticker claims)... which I am guessing is electronic and uses selective breaking. How it works or if it ever engaged, I have no idea, as I never seen any indicator lights on the dash, nor know if it needs to be manually activated prior to towing. I just made sure to stay aware and correct any slight wobble before it grew into dangerous sway.
I averaged 14mpg the first tank, of half a tank 87 octane topped off with 93, and 16mpg for the second fill up of 89 octane. (only had about 100 miles on that tank, then filled up after returning the trailer at the drop off location a mile away from home)
The trip went well and I am pleased with how the Tacoma handled the tow. I would not want to tow that much regularly, but I would think the Tacoma can handle a 3500-4000lb loaded tow on a regular basis fairly well.
Some observations/tips: My personal opinions and some things I noticed during my experience.
Plan and think about what you are doing/about to do. Think through the situations, and act accordingly. Focus on the drive, and minimize distractions. Keep a good eye on what the other drivers are doing, about to do, or may do... This will prepare you to react should they actually do that stupid thing you expected them to do... I think most towing accidents are caused by neglecting this and becoming complaisant.
Pull over to rest more often than you would normally... More so if you tow infrequently. Because it is more mentally taxing to drive while towing a load than not. (see above tip) Plus, if you do not tow regularly, then your brain is not used to the situation, and it requires an even more active thought process to tow safely and effectively, than someone with experience. This mental effort will tire you quickly.
You can tow with the transmission in D (5th gear), but you must pay attention to shifts, and the torque converter lockup. If you see the lockup engaging and disengaging more than a couple times in 30 seconds or so, you may need to be in 4th. Same with shifts between 5th and 4th.
Whenever I hit an incline that made the transmission shift to 4th, I would place the transmission into 4th until I was sure the conditions had reached the point the truck could stay in 5th, and then I would shift back into D/5th.
(This is just my opinion on this matter, others may have differing opinions. When in doubt, tow in 4th as the conservative option, to prevent issues.)
Keep the speed below 65mph... The truck seems to handle the weight better, and pull the hills without shifting down lower than 4th gear. I also got better mileage. I ran the second fill up between 60-65mph. If you want to tow in D/5th then this is what I suggest.
When I was running 70mph the mileage dropped a lot and the truck would want to downshift to 3rd to maintain speed up some inclines.
U-Haul trailers are designed so that even passenger cars can tow them, so they have very low tongues. So for U-Haul trailers, with the higher ride height of the Prerunner, I think a 3.5" drop would have worked better for me. I used a 2" drop, and I believe most of what rear end squat I did have was due to needing a little more drop for the hookup. As after I unloaded the bed of the truck of at least a few hundred pounds of stuff, the squat was still the same.
Do not use cruise control while towing... I am sure this is a rule mentioned in other places... As its dogged determination to maintain speed will make the engine and the transmission work harder, especially if you are running at 70mph. Not using cruise control can let you be gentler and smoother on the throttle, which is better for your truck and the cargo. Though I will admit I broke this rule on occasion, when on flat ground and very low traffic, and only when my legs would tire. But I would look to pull over for a rest soon after.
Sway... It is best to be observant and stop it while its just a little wobble than to let it grow before doing something to stop it. I would bet most inexperienced towers, get in trouble with sway due to not being observant and growing complaisant.
It is a self amplifying phenomenon, and I would bet the inexperienced add to this amplification without knowing it. As when the trailer starts to sway, the motion is transferred to the truck, then the driver, then the driver's arms, and then into the steering wheel. And in a new truck with a tight steering system, slight wobbles in the steering wheel transfer through the system to the tires, and make the sway grow faster. So watch out for that. Bracing on the arm rests may dampen your arms.
But I also noticed that uphill inclines and curves would stop any wobble I experienced as well. Which makes sense, as you are changing the dynamics of the situation. Curves rob energy from one side, while inclines create rearward drag, and that helps bring the trailer inline with the truck. So taking your foot off the gas and changing lanes (if possible and safe to do so) will stop any wobble before it grows into dangerous sway. Or pulling over to the shoulder... but catching it early will prevent the need usually.
Well that was my experience, and thoughts on the matter. I am no expert by any means...