mudcat34

I just bought a 2002 2500 x-cab lwb 4x4 auto and my overhead display tells me I am getting 14.5 average mpg I do have 4.10 gears in it and 305/70 tires is this normal or should I have it looked at? If this is normal what can I do to get it up around 17-18 mpg? Thanks guys

dslchk_cowgirl

The best way to figure your mileage is to hand calculate it. THe overhead is known to be off. I have an 01 similar to yours with 4:10 and it will read 15 when hand calc after a trip will come out to about 19 - 20. Having tires larger than stock will throw your numbers off unless the speedometer has been configured for the new size.

Red3quarter

I have an 02 similar to your but without the Excab. I have 4.10's and am running the stock 265/75/16's. In town I pull about 15-16 mpg and on the highway depending on how fast i'm going i can get anywhere from 17.5-19. On a few times i've seen 20 mpg. Just for curiosity is your speedo correct? Cause whoever put the 305's on might not have recalibrated the speedo.
matt


btw, welcome to the site!

HOHN

WELCOME to our (Ok, Larry's and Jack's) humble abode!

Your MPG is a little low, but not enough to indicate a problem. Check the tire calibration. 305-70 tires are 33" (actually like 32.8, but close enough).

The 4.10s are known to get worse mpg in these trucks.

For a 4.10 slushbox, your mpg sounds about right.

mudcat34

What is the best way to recal the speedo? Dealer? Also looking for a good programer or chip that won't suck fuel. If I put one on and something happens to the motor and I take it off before I take it to the dealer for warrenty work will they know I had a programer on it?

HOHN

With most products, yes.

The Smarty programmer is good in that it sets tire size, increases performance, and is impossible to detect when flashed back to stock.

The Smarty actually has a "fuel saver" version inside it. Some have reported impressive MPG gains. With the fuel saver on my truck, I can count on 20mpg hwy all the time-- even with rather large injectors.