First of all, If you have a 90 4Runner with the 3.0 Auto I would put money down you won't get 15/18. I've owned 5 Toyotas in my lifetime and two have been 4Runner 3.0 Auto's. My first was my first car and it was a 91 and only got 200 miles to a tank so you do the math. My current one is a 95 3.0 Auto Limited with 162k miles. In the last 6k miles I have replaced the HG, Timing belt, valve seals, plugs, wires, cap and rotor and 02 sensor. The auto tranny is in great shape. No fuel filter yet and the original injectors but it runs great. Strictly in town I max out at 14 mpg and on the highway 18 maybe 19. Mixed driving is about 16 or so. I'd give your trucka good tune up like others said and see where that gets you. Although if it has 220k miles the valves may be tired which can cause poor fuel economy. I also have 31 inch tires stock from the factory. So, if yours came with smaller tires the 31's are hurting you. Good luck

 

Mmmmm, I'ld take that bet with you.

I own a '95 4Runner, 3.0, auto tranny, 31's (came with 31's from the factory), 4.88's (again from the factory).
I do 95% ~ 99% of my driving in town, to and from work, with only a brief highway run (10 miles each way) to and from the racetrack every Saturday night.
I'm getting right at 19mpg.



Fred

 

If it came with 225/75r15 and you switched to 31", your ODO is off and your MPG isnt as bad as you think it is.

Also - alot of MPG has to do with the DRIVER (aka right foot).

Ive always been able to get close to EPA ratings (within 10%) on all my cars.

I have 355K of gas logs on the 4Runner to PROVE it
Last "real" tank I got was 20.5mpg...

BTW - I rarely got the 22mpg... usually 21.x

 

Correct me if I'm wrong here, but AFAIK, the trucks that're Auto, 3.0, and the 225/75r15's, came with the 3.90 gearing, that, in actuality, shouldn't affect the mileage much...

Here's what I mean: http://www.4lo.com/calc/geartable.htm

If anything, it may run a little more sluggish, but as far as "charts" your mileage would actually be a bit better. *That is unless you're jumping on the pedal to accelerate the same.

~If anything, yeah, do a tune-up, fuel pump, etc, but also run some SeaFoam through before that though to clear all of the carbonization out.

 

that chart is assuming you dont have overdrive, which our toyotas do so its not really relavent, http://www.grimmjeeper.com/gears.html is a much better gear calc

back to the question i would do what everyone else has said, tune up and o2 sensor

 

Umm that doesnt tell you mileage... maybe thats your problem....

I have seen yotas show beyond E with 5 gallons left, so just going of how many miles to E does nothing.

 

Does a bad alignment affect gas milage? also Yes I have 31 inch tires on the truck, but inside the door it suggests the smaller tire size. how much could the odometer reading be off by?

 

The odo will be off, depends on original size, so what did the door sticker say?

You will take the new diameter divided by the original diameter.. for more accurate correction info use the rev/mile figures available on mfgrs website and convert that to a diameter and use that for the math.. (eg my 35's only rolled as a 33.7, so using 35 for the math wouldnt have been correct).

 

in the door it says P225/75R15 S I have 31x10.50R15/C on the truck.
what website are you talking about? what about the allignment?

 

I use bfgoodrich.com, as my OEM tires and current tires are BFG's, use whatever mfgr's site of tire you have...

Using BFG numbers your speedo/odo are reading 7.3% slow...

A bad aligment may have a minor effect on mileage, but mostly on tire wear.