Did the Suby have a turbo though? You'll never get the returns of a simple tune on a naturally aspirated engine with a tune as you do on one with a turbo. You'll get improvements, but don't go expecting what you got on the Subaru.I really think there is some added efficiency to be had with letting the engine breath, and if you are inclined, a retune for 89oct or better. Cam timing/phasing in motors can accomplish quite a bit, including the low end tq you are looking for. From the factory, they have to tune it for emissions standards...re tuning the ignition timing, cam phasing, and fuel trims for a little better fuel would most certainly pay huge dividends. Last car i tuned, for example, was my subaru. It was rated at 26(i think?) mpg from the factory....when i finished with it, it made well north of 400hp at the wheels and routinely trimmed 32mph on the highway. It was all in the calibration....after ive run it for a while Ill talk to the guy with the Nissan tuning software and see what he thinks, but there is definitely gains to be had.
EDIT: Oh, and the Rugged Trails? I'm not that impressed with them. For the seasonal roads and few trails I've done, they've been fine. A bit short on traction in the wet, but nothing horrible. They have been disappointing in the snow though. Yeah, they aren't snow tires, but they perform worse than I thought they should/would have in the snow. I'm not in a major rush to replace them, but I certainly wouldn't buy them given the choice.
I think goodyear duratrac will be what I go with when I replace these. Ill run the stockers until I need to change, though.
Honestly, the only feature the 4runner has that I wish the x had was the slide down rear window. I like the x more than the runner otherwise. The price difference makes it even more of a no brainer.