My 08 3.0 is a bit sluggish, but popping it into sport mode or just keeping it in a lower gear takes care of it. Going to the 4.8 is a catch22, you're going to use more gas (if that's a concern) either way, over acceleratin the 3.0 or normal acceleration on the 4.8 probably results in the same MPG.

I will say that once it's past 2nd gear, acceleration isn't a problem. I'm hoping that once i get a few more miles on it it will loosen up and/or the tranny will adjust to my driving (i.e. hold lower gear longer to get moving faster)

I haven't noticed a noise issue.

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