Hi I have a question. I have a 1993 Suzuki Sidelick. IT has 30/9.5 mud t. Stock gearing. 5spd. 4x4. Soft top. 2dr. since I swapped the mt's on I have been averaging about 18 miles to a gallon. That just seems low to me. Is this normal? Every tank of gas it usually gets about 10 miles of crawling and the rest is highway. And I only get about 180 miles on a full tank tops. Just wondering if it's normal and what kind of mileage you guys get. Thanks

Stock gears and 30s, ya,  I'd say that's normal

I get 16-20 with 33s and 5.83s

Don't forget that your odometer will read lower than before.

WOW!!   i'm getting just about 32mpg cruising at 3500rpm (almost 65mph) on stock tires/gears in my 1991 tracker 1.6 8v, 5speed.  was going to lift it and put on 30" tires, but, now with the gas prices and if there is really that much difference in mileage, perhaps i should reconsider!!
 

i get on 33 litres about 330kms i used to get about 390kms before I changed to 235's now I have figured that i changed by 3-5km's at 100km/h so that is only 345-250km per 33-35 litres  and that is really baby'n the throttle like no more than 25% usage on eccelerating.

I'm getting about the same with my 4 door and 30's I also have 5.38's which should help but don't! Make sure the tires pressures up. It sucks for ride but helps the mileage.

I am going to try the seafoam thing and see if it helps at all.

Yeah, remember that you're traveling more miles on a tank then your odometer shows since you've got bigger tires.  Also, have you done a tuneup including setting the valves and timing?  I recommend advancing the timing about 2-5 degrees beyond recommended, it helps with pep and mileage (IMO).

Don't forget that your odometer will read lower than before.

If your original tires were 28" dia and these are 30", your odometer will be off about 14%, improving your mileage calculation about 2.5 mpg.  While passing smokey with his radar, keep in mind that your speedometer will also read about 14% slow, too.    All this assumes you haven't changed the speedometer gearing.

i ride on 30's and get 400km to a tank, which works out to about 250 miles. i used to get more but lost some milage after installing a header, and 2" exhaust. although wether i drive hard or light i get the same milage, but hey it's still better milage than any other 4x4. 

Im showing about 200 miles a tank on 31's with 5.12 diffs in a samurai......  Any guesses how far off my odometer is?

.....  Any guesses how far off my odometer is?

The effect on your odometer is basically the ratio of the diameter of the new tires to the diameter of the original tires.  If your new tires are 31" and the original tires were 28", your odometer will read low, (28/31) * 100, or approximately 90% of the correct reading.  If your differential is not stock, you will have to figure the ratio of the old to the new.  These calculations are approximate, because the inflation of the tires, amount of treadwear, etc. affect the effective diameter.  If you watch your odometer and the mile markers along the highway for several miles you can verify your calculations.  Another way is to compare your speedometer reading with one of those radar trailers used by some police departments to encourage people to slow down.

OR you could use the calculator on my site
look at the bottom of my posts, there is a
hyperlink there for many common tire and
gearing calculations

Wild

I only get around 12-14mpg on my kick

    kevin

Lead Foot

I only get 8 km/l on my sidekick , 5.12 and 265/70-15 6" lift big exhaust.

That would be arround....19 mi/gal