will TOD disconnect improve MPG?

[Maugan_VX]

it would probably help you more to just moderate your driving style, and keep the vehicle in tune.

[VehiGAZ]

Yeah, there's too much 4WD running gear that needs to be turned even when in 2WD to make much of a difference in mileage. 12-13 mpg seems very low, though. Go for a tune-up, and try some injector cleaner, too.

[moon buggy]

Just as another measure for you, with my JDM model [3.2L sitting in 2High - rwd] for the tank according to my Japanese owners book, I can get 85L of fuel in and the fuel light comes on at 8L left, I refilled mine when the light came put 76L and travelled for 530KMs, mix of short round town plus some 25-50km highway runs, not revved over 4k, Power button on when i remembered..so according to my fuel calculator..that's ~ 20mpg, the premium fuel I use is 95 octane, the best available here is 98 octane ....but is like another 6 - 8 cents a litre more, taking that fuel to nearly $1.20 AUD per litre !!, so I just opt for 'regular' premium..

..also my VX even with 20s at 275/45 are supposed to only give a speedo error of 1 - 2% tops, but its actually around 5% [used GPS plus 2 other cars to compare speed to indicated, speedo shows more speed than actual road speed], ....the speedo error was even worse with the original 16s close to 10%...anyway ...based on speedo error..around 19mpg..

[SGT.BATGUANO]

530 km = 329 mi

85 L =22.5 gal

76L = 20gal

So you're getting 14.5 or 16.5 mpg before tire correction

[moon buggy]

Oh well, I was pleased to get 530ks with the light going on...and in view of fuel efficiency [lack] ..I am glad Isuzu fitted the capacity fuel tank [larger] that they did to give a half decent touring range.

...hmm..I'll recheck my numbers again, my fuel calculator is a bit old [slide rule type]...but doing the simple divisions on the above 76L/530kms = 14.3L/100kms which is [on reflection] up there with the bigger 6 cylinder 4wds, in our market [Prado/Harrier/Montero]...

Will fuel/oil ever get back to under $50US a barrel..$66 today !!

[PeteVX]

Sounds like its not worth the effort then, thanks for the input though, i didi put fuel system cleaner through there a couple of months ago but it didnt make any difference, i replaced the pcv valve too and have a K and N filter on it, i dont drive it too hard but have had the AC on pretty much all the time for the last few months...gets pretty humid here in Minnesota!

Ohhh well, like i bought the car for its fuel economy right? hah hah!