Although I live in Western NY, elev 600 feet, I've driven to and in Colorado many times. I had a 3.0 until it was totalled by an errant pick-up, but now am in a 4.4. Both were/are automatics. From my experience, you won't notice any difference on the interstates. I've driven west from NY on I70, I80 and I90, I25 south to Raton and NM, north to Wyoming, etc., and there will be little, if any noticeable difference. But there will be a diff in the mountains. I've taken both to the top of Pikes Peak, and do notice the stronger pull in the 4.4. Remember, though, that every engine loses 5-6% of its power for every 1000 ft of elevation. So if you live in Denver, at 5200 ft, and drive to Aspen or Vail, you'll notice a loss of throttle response at elevation. This happens with all cars, however, so it will be less noticeable relative to other traffic. You'll just be pushing a bit harder on the "go-pedal" at higher elevs. The fuel mileage diff is negligible, except in the mtns, where the bigger engine will tempt you to push harder and mileage will fall off accordingly. More power in the 4.4 equates to more fuel when you push it, which is almost always in the mtns. I like both pretty well, but the 4.4 a bit more - only for the extra power. Here in the flats of NY, the 4.4 is stronger than the 3., but much less noticeable at elevation.

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Sageriders
2011 328, Water [blue], Saddle
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