Any suggestions besides putting the stock tires back on, I know my gearing is way off but the truck runs great. I am getting 10 mpg in town.

During my test I could only get 16mpg with a all stock 88 SWB. I tried my best, coast to a stop, coast down hills, easy acceleration.
www.fueleconomy.gov said I could get 17mpg but it's only estimated. I think I did pretty good to get within 1mpg of the estimate. If I drove my normal style I would get 14mpg.
It must take serious gas to get those big meats turning.

How far is your work drive? Ever think about a econo box?

<img src="/forums/images/graemlins/patriot.gif" alt="" />

Sorry, I can't help you there, but I can tell you that my truck is about the same. Fuel guage drops noticably for just small trips around... and I used just under 3/4 tank for 150mi of driving home from school, which was almost all highway, trying not to spool the turbo alot...

Brendan

This is my commuter and it's a 12 mile trip one way.
I probably should have gone with some alum wheels.

Are they really that much lighter? My brother has a set of mickey thomson alloys with 31s on them for summer tires, may be I should give them a shot and see if it helps?

Have you taken into account that the large tires are throwing off the reading pretty good? <img src="/forums/images/graemlins/cyclops.gif" alt="" />

I have 31's on stock alums and I get 14.5mpg. Are you taking into account that 35's are throwing your speedo and therefore tripmeter off? P.S. I did NOT adjust for tire size to get 14.5mpg. My trooper diesel gets almost 25mpg same driving. The only problem is it's geared so low you can only go about 55-60

well I judged mine by the trip from tanking up at my college and driving straight home which I used to be able to do with just less than half a tank.. now it took 3/4 tank which isnt too much more, considering it is turbo now.

I am just happy its working though.

Mine is a non turbo and w/ a 32/36 Weber, with 31's and I get about 200miles per tank 15.9 gal tank. Thats apprx 12.5 mpg. By the way, That is from red light to red light wide open to idle wide open to idle. I am not kind to my motor, I run premium gas, Mobil 1 oil and pure 1 filters. I pound this truck <img src="/forums/images/graemlins/evil.gif" alt="" /> <img src="/forums/images/graemlins/evil.gif" alt="" /> <img src="/forums/images/graemlins/evil.gif" alt="" /> and I give it what it needs to take it... And I get 12.5mpg with factory steel wheels. I think steel or aluminum will not change anything for you, You put on the 35"s, U play, U pay.

I am coservitive off road though <img src="/forums/images/graemlins/baby.gif" alt="" /> <img src="/forums/images/graemlins/shiner.gif" alt="" />

I haven't changed my speedo gear out yet and thought my mileage had declined drastically with the new 31X10.50R15's. After considering it a bit, I gathered RPM data for the old Michelin LTX LT 235/75R15's and the new Bridgestone tires from thier respective web-sites. I divided the new RPMs by the old. => 681/727 = ~0.937 I then divided the odometer reading by this number to get the actual milage. For example, a odometer reading of 275 miles is really about 294 miles. This will change my MPG calculation by 1 MPG. I am now getting about 16 - 17 MPG (adjusted). I used to get 17 - 19 on the old tires. Of course my driving style changes that drastically if I start getting lead-footed.

I should really get that 24-tooth speedo gear per DougB(?).

You are running 35's though. I would assume 10 MPG is pretty good?

I would roughly calculate the RPMs on 35's at 585. For the example above, divide 250 by 0.805 (585/727). The substitution would be about 18 MPG, all other values unchanged.

I dunno...