9r12.crom tire size adjustment has no effect on speedometer.

[skidplate]

06 Wrangler Rubicon 6 Speed Manual 18k miles. 7500' just above Boulder Colorado

I'd read a number of times on this forum from various users that they couldn't get the Tire Size adjustment to fix their speedometer. I just uploaded to the 9r12 the other day. I had the 9r8 version. Never really saw much difference between tune or no tune but it previously didn't show a 33 or 35 tire size at all so was excited to see it on the 9r12. And I thought maybe something good had been done to improve the various tunes along the way. Just wishful thinkin. A lot a good that was. I checked them both with a GPS in the jeep going down the road. I tried the Quick way, the Full Tune way; I even tried to change the Gear Ratio option... NOTHIN.
NOW I question weather ANY of the Tunes have had ANY effect. This may all be the Clean Car syndrome. You know what I mean. It always seems to go faster after it's been washed? Maybe it's the same after we've thought we actually changed an importent parameter... whether it really did or not. I've tried to think positive and believe that some difference has been made to justify buying this thing but I'm beginning to think this has all been a waste.

[j33p]

So your implying it's all a scam ? I was disappointed when the tire fix didn't work for my WK, but it does now, and the tunes do make a difference on my WK.

I also have a modified TJ myself, I wouldn't even bother putting any type of tune on it, now with your electronic speedo I can see the need to fix it as it would annoy the hell out of me, but running a modifed box down the road is what it is, the tune isn't going to fix aerodynamics at all. I think I only get about 12MPG depending on the wind direction.

I think I saw some other posts about the same issue, but it ended up being fixed one way or another. It took some time, but I am a happy customer now, I am sure you will be eventually as well.