2012 Toyota Tacoma Double Cab 4X4 MPGs....

[slowmover]

A truck is therefore a business proposition. One must know annual fuel cost, dollars and gallons versus miles. Absolute mpg numbers aren't as important as keeping average mph high versus engine hours. It's a different strategy, and dictates different tactics.

[aardvarcus]

Originally Posted by skyking

Not for the OP's 90% freeway driving. Like I said before, you can't effectively P & G at freeway speed, and for sure not in a comparative drag bucket.

I think you need to reread my post, specifically where I stated "the 18% better final drive would outweigh the advantages of the manual."

[skyking]

Yes I jumped to the tail end, sorry.
My "new" truck is a good example. It has a higher final drive ratio, but the reliability alone of the auto is not working for me. I was happy to find a 6 speed manual.
I've had the transmission in the truck in my sig out twice. It is painful.

[aerohead]

Originally Posted by Asanelli

So you implying the manual is the way to go??

I'm uncertain that we have any known quantities at all to work with.We have no idea what your BSFC is doing one way or the other.
Hucho is going to tell you to streamline the hell out of the truck,and do whatever you can for rolling resistance,and only then,when you're finished modifying,figure out your gear-matching from there to optimize the road load reduction.
If you initially do the gearing,you may shoot yourself in the foot if you modify the truck later.
Gearing is at the end of the efficiency equation,not the beginning.

[aardvarcus]

Once you got the truck streamlined and your rolling resistance down, one solution to the 4.0L V6’s less than ideal manual transmission overdrive gear ratio of 0.85 is the URD Tacoma T56 Transmission Swap Kit. The URD T56 Swap kit is designed to use a T56 transmission that was originally used in the 1998-2002 Chevrolet Camaro.

T-56
1st=2.66:1
2nd=1.78:1
3rd=1.30:1
4th=1.00:1
5th=0.74:1
6th=0.50:1
R=2.90:1

Going from 0.85 OD to 0.5 OD is a 41% reduction in RPM! To maintain 4x4 you could either run a specialty T56 transmission setup for a bolt on transfer case, or run a divorce mounted transfer case (i.e. Divorced Atlas II).