I just bought a 98 Toyota 4runner 2wd auto transmission with 120k miles and when we got home from getting the truck 100 miles away we noticed the the odometer was not reading right, it seams to be going real slow on the last number, so can this be from a faulty odometer or speedometer sensor, or can someone could have tampered with it? any input on this would be great, thank you.

Im not sure, I will check and let you know because they don't look like big wheels and tires.

check your wheel size, if you have 16'' rims, u should have 265/70 tires, if you have 15'' rims i believe you should have 265/75 or 245/75 tires.

you said its "slow" so that means u probally have bigger tires than stock size.

They are 235/75/R15

That's why it's reading off.

It's a minimal difference really but the tire size is supposed to be 225/75/15.

I had the original size the same on mine too, but now im at 265/70/17, which is a difference of a 28.3 inch tire to a 31.6.

My speedo/odo is pretty off lol.

Here are the differences:

Speedometer reading is 2.1% too slow.
When your speedometer reads 60, you're actually going 61.3mph.



Which is really not that big of a deal. Mine is ridiculously off.

My speedo is 11.7% off, speedometer reads 60, I'm actually going 67mph.

Its better that way, then it appears the vehicle has less miles then it really has (better for resale), mine is the opposite, i am off i little bit, when the speedo reads 65 i am doin 62. Nothing major.

You guys really think a .5" will make that big of a difference?

Noway he's visually seeing in 2% differnece in the odometer.

How far off is your odo? You said you drove it back 100 miles, what did it read?

whoa..i thought the first 3 numbers were the "width" of the tires...and the middle 2 numbers were the "height"?????????????? i always thought 265/70 were wider than 245/70....but 265/70 were shorter than 265/75!
whats the deal with the 3 first numbers then?

b/c i bought a pair of 275/70/16 for my front tires...uh oh...

You are correct the first 3 numbers correlate the width ratio. That's why I'm confused as with the two tire sizes there really only is less than a .5" difference. The height of the tire is based on the next two numbers. For instance my tires are 255/85-16. The 85 dictates my 33.5 inch tire diameter not the first three numbers

yea..so either childrenofbodom is wrong, or hes right and im missing something...however i remember reading somewhere that the second set of numbers is the ratio to the first set of numbers...so like 265/70 means 70% of the 265mm... but like 275/70 would be a taller b/c its 70% of 275....

grr someone clear things up? have i not been running stock tires all this time?! i thought the second set of numbers was what really made the difference in the height of the tires.

yep he was right, the 2nd set of numbers is the ratio to the first set..in which my case i have 275/70..which turns out to be 192.5 mm...whereas recommended size is 265/70 which is 185.5 mm ..so i really have a 7mm lift! WOOT!

Well when I got it this Thursday it read 120,84 and the drive home was about 100 plus miles and now it reads 121,02 not to mention the driving we have been doing around town, this is way of to me. I don't know if i should replace the odometer with a used cluster close to what i have or what? don't know where to start. I hope this thing doesn't have a ridiculous amount of miles then what I paid for.

Yup, exactly why 265/70/17 is a 31.6 inch tire while 285/70/17 is a 33 inch.

I heard somewhere that the second number is a percentage of the first number... so the height of those two differs as 70% of 285 is a larger number than 70% of 265.

So likewise 235/75 vs 225/75 would account for just a tad bit more height.

Don't worry about your miles, if anything it's really not off by really much at all. It's such a small difference. Just imagine 11.7% off like mine, or some of the people with 35's and 33's.

If it really bugs you, you can look into Dakota Digitals speedometer correction box, which I will install soon. A member here, 240m3srt, has done this to account for his 35" tires.

And hey, like John said, looks like you have less miles!