I've had my '13 4WD Platinum long bed for five months now, but compared to my '11 2WD Platinum standard bed, it's a dog on the low end. And it gets 1 MPG worse: 12.2 vs 13.4.

I'm not sure if it's the 471 pound curb weight difference, the open 3.55 vs LS 3.73 gears, and/or the heavier and aggressive all-terrain tread of the Nitto Terra Grappler G2's vs all season Nitto 420S (both are 31" diameter), but the '11 flat out hauls from a stop and is extremely responsive to the throttle, unlike the '13. Both have 6.2's. The '13 has clocked 96k and is probably on its original plugs, whereas the '11 is almost 157k and I'm sure went through a plug change at 100k.

As I'm not the original owner of each, I was wondering if the '11 perhaps had a tune programmed into it which explain why it drives like a different beast vs the "stock" '13. I'm now worried about what the performance will be like with nobbier 33's on the '13. I will miss the '11 when my brother claims it at Xmas so I am working to close the performance gap. But I'm curious if the difference is actually normal between 2WD vs 4WD, long vs standard beds, 3.55's vs 3.73's, street vs all-terrain tires.

Will be performing the 100k service soon, which includes new plugs, have headers in storage for a year now to throw on, add a tune, and will regear when I lift and go 33's. Last stop would be forced induction.

 

There's a significant difference IMO, I drive my buddies truck which is 4wd and only a crew cab and it's much more sluggish and heavier feeling than my Screw rwd. Just a butt dyno, but both of us noticed.

 

4wd will have increased drag and less hp to the wheels due to added drivetrain components up front. That front axle weighs a lot more than some think and now you're also attaching it to and added weight and hp loss thru the xfer case.

Every little bit adds up.

If you put identical trucks side by side on a track, one each 2wd and 4wd. the 2wd will smoke the 4wd everytime. It's not perceived, it's fact.
.

 

It’s the extra weight with less gearing combined. My 2013 Platinum 6.2 Screw 4x4 goes good with 3.55 gearing. I average 14.1 MPG.

 

I went from a '09 4WD Plat 5.4/3.55 to the '11 2WD Plat 6.2/3.73 and I always attributed the massive difference in performance to the 6.2. My '13 has shifted that paradigm.

The '13 still hauls and holds it's own at freeway speeds, and from what I could recall, has more power up there than the 5.4. I know the heavier 4WD will be slower than comparably equipped 2WD but wouldn't believe it could be "smoked" by it. My butt dyno notices a significant difference and "smoked" would be an apt term in this situation. Alas, I won't be having as much "fun" in the '13, but someday hope to rectify that...

 

All of those things combined. But the 3.73 vs 3.55 is probably the biggest contributor.

 

The 6.2 is way faster than the 5.4, the difference wasn’t the gearing. I also have a 5.4 but with 3.73 gears, it goes good with the 6 speed behind it. The 6.2 with 3.55s will still leave it ten miles back when hitting the gas, it just has a lot more pull to redline.

 

If you're going to re-gear, go with 4.10's. The 3.73's would only be a minor step up from 3.55.

 

That or 4.30's since I'll be putting 33" Ridge Grapplers.

 

4.30 would be a good ratio favoring performance, but I think you find them non-existent for your truck. I went through this when I geared my '05. It has a 9.75 rear and an 8.8r in the front, which I think is the same as you. I forget which, but one of the axles had no 4.30 available for it. In that case I took the next step and went 4.56 . The truck has a 4r75 with a fairly tall 1st and 2nd, and 35" tires. It makes very good use of the deep gearing. With 33's behind the 6r80 I think it'd be overkill, although it would go like a rocket.