well I think I can help you out here. I am in the waiting for my BD with a 2.7. I ordered the larger engine because my base is at 7000 feet, and I regularly go over 11000 foot passes, with a smaller trailer, and my previous 4Runner was like a lame duck, so I promised myself not to under-power my new build.
Fast forward to today, I have been driving a loaner BB with the 2.3 4 cylinder for the last 3 weeks and 2000 miles, and I can tell you without hesitation, this machine is awesome. It is so good, I kinda wonder why I took the larger engine. The low end torque on the 4 cylinder is simply wonderful, there are no vibrations and running at 70 MPH with only like 1500 RPMS thanks to the 10-speed trani. Seriously, this engine mated with the 10 speed was made in heaven, or at least that is how it feels.
I have taken this thing all the way to 11000 and without hesitation it spools up and accelerates like a flash.
You will have no problems what-so-ever towing a 3000 or 3500 lb trailer, and you will not regret your 4 cylinder purchase.
I hope this helps
Thomas
