New here to the forum-- I am thinking about buying a 01 or so Grand Vitara 2.5 4x4  for mostly town driving  what should I expect for fuel economy for this with the auto transmisson?  Do the old Sidekick Sport models with 1.8 and auto have much poer and get much better fuel mileage?  Thanks in advance for and advice!

I get 17 to 19mpg in town.

I have a manual V6, and I get (in US gallons) 19 in winter and 21 in summer.  I'd expect an auto to be 2 or 3 mpg worse.

You might get 2 mpg improvement with a 1.8 Sidekick, but I'd find it underpowered.  Still, in town, would that matter?

Had a '03 GV 4x4 2.5L V6 and auto trans several years ago.

Best mpg was 19mpg in town and 22-23mpg on the freeway.  This was with stock car like tires and the vehicle two or so years old and under 40,000 miles.

Put LT225/75R16 mud tires on it and it dropped a mpg or so most of the time but never saw the freeway mpg again.  Like it was capped at 19-20mpg.

With another decade and unknown mileage/maintenance/neglect?  Good luck.

I get 19-20 mpg in town and 23-24 highway.  With 2 inches of lift and 235/75/r15 at tires

Seems to be a pretty common range there. I have a 2001 4 door 2.5 V6 and get 18-20 city and 22-24 hwy. That's with Jeff's 2" lift and 235 75 15's on it, which by the way  is the way I feel the vehicle should have came stock. Once a year I also tow my 16' boat from Wisconsin to Arkansas with no problems.

Assuming my tank is 55 litres (14.5 gallons) which i think its, then Im getting 17mpg mixed highway and city.

If you have a 4 door it should be closer to a 17 gallon tank.  I just returned from another trip to Nashville, TN.  Took the Dixie Highway for most of it versus running the entire trip on I-65.  Pulled 27MPG going down and on the return I traveled west of Upton to Clarkson, KY to pick up some bee supplies.  Lots of DEEP valleys and winding roads on that 20 mile leg... ended up with 25MPG average when I returned home.  I had 365 miles on the odometer when I arrived in Nashville and an indicated quarter tank of gas left in the tank (4-5 gallons), and pumped 12.56 gallons of premium into him.  Yeah, I double checked the receipt for gallons pumped.  Crazy good gas milage!  This with the 2 Liter engine, 5 speed, 4.88 gears and the new Mastercraft Courser C/T tires (which were surprisingly smooth driving).

Assuming my tank is 55 litres (14.5 gallons) which i think its, then Im getting 17mpg mixed highway and city.

The tank capacity should be of little relevance - what you need to look at is how much gas you're putting in to it.

I changed the O2 sensor on one of my vehicles a few weeks back - every Saturday morning since then I go to the same pump, fill the tank until the pump clicks off, note the amount, note the milage and do my calculations - I've been putting between 17 & 25 litres into a 55 litre tank.

Agreed, Fordem.  There will always be a little bit of variance to the MPG figure (unless you are actually using laboratory controls) but not a whole lot.  Another important variable (I think) is the type/size  of tire you are rolling and the type/quality of gas you are running in your truck.  I buy premium at Day's Marathon without ethanol additives.  Ethanol isn't the best fuel source for power, clean engines or fuel economy.

To be quite honest, I've always scoffed at folks who monitor fuel consumption and can report down to two decimal places - even if you used lab grade measurement equipment, operation of the vehicle in the real world has too many variables - as an example, taking my daughter to work in the morning is a journey of a little more than a mile, and includes two traffic lights - if I'm lucky, I'll spend less than 30 seconds idling at the lights - if I'm not, I'll spend more than five minutes at the second light - the queue is often long enough that it will take two or three cycles before I can make it through the intersection.

Even outside of the city - things like the direction & intensity of the wind (especially when you drive a brick on wheels) have an impact.

Agreed.  There are too many factors and variables that just cannot be controlled or predicted in the real world.

i have to check mine i have the 2.0L with manual trasmission with a 2" lift and 225/75/16 tires. the spedo is off so i cant really check the mpg but i know it made it better on highway, with the stock 215/65/16 tires at 100km/h the tach was around 3100-3200 rpm, with the 225/75/16 it only now revs around 2400-2500rpm so it burns less fuel highway wise,around town it is a bit underpowered beacause of the tire size but the mpg is about the same. i have to check with a gps or sumthing

I've got continuous data on my GV V6 since I got it in Apr 2005.  The mileage has never been worse than 22 or better than 27.5.  The running average is 24.5.  The highs coincide with hot summer weather, and the lows with cold winter. 

These are Imperial Gallons, of course.