Speedometer error correction

I've searched and read the various threads on the speedometer error but haven't found any info on correcting this error. In my truck an indicated 65 is actually 59 according to my Garmin.

In my previous life as a Dodge Ram owner I know that the dealer could reset the computer for the correct tire size that you were running. This would minimize the speed error. Alternatively, you could put in the wrong tire size to get even less of an error. Does anyone know if the Toyota dealer can do this? I've tried calling my local dealer but haven't been able to break through to someone with enough common sense to fully listen to my question.

 

with the right computer, you can. (all dealers should have one)

i too see a little difference in the speedo. (scangauge tells me so)

 

My issue with this is since I went 32x11 is that my GPS & speedo are exactly in sync at any constant speed AND have been beside unmodded cars with digital speedos (civic hybrid for example) on frwy at dark where you can see their readout and mine matched theirs too BUT have been pulled over a coupla times with the cop sayin I was doin 75 when my speedo was on 70 with cc on. I think the cop's radars were not calibrated correctly, they were shootin a different vehicle or don't know how to use them. Bet their radar woulda said I was doing 10mph while he had me stopped. Even checked it with another person's different brand GPS and was in sync with it at every constant speed.

Not doubting OP will have trouble with dealership on this matter. I would try somewhere else.

 

no your wrong. i have 35s on my truck the faster you go the bigger the margin. for example im doing 35 on my garmin but truck shows 31. garmin says 78 speedo saying 72. thats not the exact but you get the idea.

 

The stock 31" (265/70-16) tires have my speedo off by ~3 mph... reading faster than I am going... ie. at 65 on the speedo, I am really going 62 mph.

Going to a 32" tire (265/75-16) has been reported to drop it to right on.

 

I had 265/65/17 on my 2010 TRD Sport and my speedo was 4mph faster than my TomTom, installed 265/70/17s and now I'm dead on with Tommy Boy. An added effect seems to be reduced gas mileage but I hoping it's the crappy winter blend gas. I guess I'll find out in the spring.

 

While the speedo is now spot on your odo will be off. Give and take I guess. You should be able to recalculate your mileage and find the gas mileage should come back some. I ran into the same problem when I went to 265/75/16s.

 

So you think if I recalibrate my UltraGauge I would see the mileage correction? You don't think it can be attributed to the crappy winter gas blend?

 

I just deal with mine being off. Mine isn't off that much, only 2-3mph at highway speeds.

 

I have 275/65/18 Duratracs which are 32.1" and I believe it is dead on. Multiple GPS comparisons, multiple random vehicle speedo comparisons, mileage marker and odometer comparisons...good enough. I suppose I have defensive driving and lawyer for those who think not.

 

X4...I'm right on per GPS and running next to my wife tracking her spedo with my 285/70-17. Was pretty far off with stock tires.

 

You can buy a device to adjust your dash to match your tires. Only 1 or 2 of em out there compatible with tacoma that I saw though.