Towing travel trailer: Tacoma or 4Runner?

We've got a 2011 4Runner, and want to tow an Escape 21' travel trailer that weighs 4300 pounds, ready to camp. The 'Runner's towing capacity is 5000 pounds, while the Tacoma with the full tow package is rated to tow 6400 pounds.

We like the SUV and have no reason, other than towing, to own a pickup truck. We are new to towing, and don't get the trailer for a few months, so in advance we are trying to figure out how to tow the 21' safely, and to maintain a decent speed on steep grades like mountain passes.

When comparing the specifications of the two vehicles, though, it's not clear why the Tacoma's towing capacity is rated 1400 pounds higher than the 4Runner's.

* The two vehicles seem to use the same 5-speed automatic transmission, with the same gear ratios.
* The 4Runner produces 34 more horsepower--270 @ 5600rpm vs. 236 a@ 5200rpm.
* The 4Runner produces 12 pound/feet more torque--278 @ 4400rpm vs. 266 @ 4000rpm
* The 4Runner's curb weight is 473 pounds higher--4750 to 4277 pounds.
* The 4Runner's wheelbase is ~17.6 inches shorter--109.8 to 127.4 inches.
* The track and width are nearly identical.
* Here in Canada, both vehicles come with a hitch, a transmission fluid cooler, and pre-wiring for towing.

My questions are:
1. The wheelbase of the Tacoma is 17.6" longer. How much of its higher tow rating would be due to the truck's extra length?
2. Am I correct to assume that the 473 pound weight difference would directly account for about one-third of the 1400 pound difference in towing capacity?
3. With their power and torque ratings so similar, would the Tacoma be able to pull the 21' up a steep grade any faster or with less strain than the 4Runner could?
4. What factor(s) am I missing that would see the Tacoma's tow capacity rated so much higher?

Thanks for any thoughts you have from your experiences while towing with your Tacoma, 4Runner, FJ Cruiser, or similar tow vehicle.

 

I pulled a 21' Ultralight, it was around 4000 lbs? Anyways, I pulled it with my 2011 TRD 4.0L 6 spd manual, It didn't pull too bad on the flats, didn't like the hills much at all, the truck struggled quite a bit, was in 4th sometimes 3rd to pull hills, couldn't pull in 6th on the flats very well either, and to get good mileage, I had to stay under 100 km/hr or it sucked up a tank every 350km. also squashed my suspension too, not really meant for towing I suppose. I will not be using my Tacoma for pulling a holiday trailer again, just not worth the wear and tear in my opinion. I'm not familiar with the auto trans, but I know from experience with our work trucks (chevy, Dodge) that if you don't pull in tow mode you will burn out the torque converter. Didn't really answer any of your questions, more of a disappointed rant. Thought I'd be able to tow more than it did.

 

Look into gearing. The tacoma (at least, the one you're looking at with the tow pkg) has 3.73 stock gears. IDK what the 4runner stock gears are. Type of brakes also apply

 

I have been towing marginally heavy loads my entire life with Toyotas. My experience and opinion is that the Tacomas are rated a little high, they are capable but over 5k seems like a lot. Wheelbase does help, the extra weight on the 4runner actually takes away from its ability to an extent. Without getting into technical aspects of gearing, coolers, and other equipment there shouldn't be a large difference between the ability of the two. Towing capacity comes down to legal matters with manufacturers and not it's actual ability.

 

The differance could be from the different rear suspention setups between the truck and 4runner. The 4runner could be a little softer and more bouncy than the truck. You should get a weight distrabuting hitch and a sway controller to go with the set up.

 

Very helpful advice, guys. I'll do a trip with the 4Runner and see how it does. Definitely getting a WD hitch, like an Andersen.