Just Regeared Speedo Recalibration?

So I've got a 2wd 6spd V6 SR5 Access cab.
When I picked it up it early 2018 it had 265/70/16s.
Not long after I put on some 265/75/16 AT3 4S and my speedo would read about 65 when going 60mph which was livable.
Well I just drove home after regearing to 4.3s,adding a Trutrac and Now I'm reading like 72 at 60mph.
2850rpm at 70mph(gps mph) if anyone is curious.
I plan on upgrading to 285/70/17s once these tires need replacing.
I remember reading about a couple different devices that can recalibrate my speedo.
Anyone got any suggestions?

Edit:

Looks like the Hypertech 730107 is what I'm after.
Guess I should have just searched before making a thread.
If there are any other options I'd love to know.

 

Something is wrong. When go to a taller tire with factory gearing the speedo should be slow, when you added the gears it should have gotten you closer to being correct. How are you calculating the speed? Ie. I have a 285/70/17 on my second gen and at 70 I’m actually going about 75, if I went up a gear it should get me closer to being correct. I’m assuming this is a 6 lug prerunner

 

It is a 6 lug prerunner.
I'm using waze/google maps for speed reference over the last 2 years
But everything I said was correct as to what has happened to my speedo.
Why that is...
I have had the abs/brake light on since ive had it.
Maybe that has something to do with it?

 

Could be. The speed reading come off the right rear abs sensor/ wheel speed sensor.

 

Check for ABS codes

First, connect terminal 4 and 13 of the OBD-II socket (under the dash in front of your left knee) with a jumper wire. (Those are the 4th from the left on the top and the fifth from the left on the bottom.)

Turn the ignition to on. You'll notice lots of flashing lights, but just pay attention to the ABS light. Normally, it should be rapidly and steadily flashing, twice per second. If it has stored a trouble code, it will instead be flashing a pattern that will coding a two-digit number. There may be more than one code being flashed out. It will just repeat the code over and over, so you have plenty of time to figure it out and write it (them) down.

NOW you can clear the codes. Just tap the brakes rapidly 8 or more times, about two taps per second. You don't have to jam on the brakes, just tap them enough to blink the brake lights. If you're successful, the ABS light should return to its normal fast blinking. Now remove the jumper wire, and finally turn off the key.

Now when you turn on the key, the ABS light should just do its normal light for three seconds and go off. If it comes back on, you still have a problem

 

I'm gonna do this tomorrow when it's daylight.
I think I'm gonna finally get to the bottom of this fucking abs/brake light after almost 2 years as a birthday present to myself.
I know its not a break in the harness cause I replaced that a few months ago and it shouldn't be the abs sensors because I thought my mechanic replaced the 2 rear ones when I had my front coils pressed but he may have not put them on (wouldn't surprise me as he didn't put on the new washers n shit at the top the first time around).
I just went out and smashed the brakes from about 40mph and they did lock up (definitely smelt burnt rubber lol).
Thanks guys.

 

Go with the hypertech, I am running it on mine bc after regearing to 5.29s, it was reading 20% more on the speedo than actual. My recommendation is to leave the USB cord plugged into the unit that is used to program it and run it from up behind the dash where the box mounts down to the driver side kick panel near the OBD2 port. This will allow you to easily plug in the usb and reprogram it to dial things in just perfect without needing to take the dash pieces out again (which also is very easy, I was worried about doing it myself but watched a video and it was a piece of cake). Great unit overall, takes a little dialing in, but it's 100% worth the money imo

 

Just ordered it.

https://www.amazon.com/gp/product/B001G9AMES/ref=ox_sc_act_title_1?smid=A3C8VUFPRQ0DLI&psc=1
$189.84 shipped no tax.
The first option Amazon gave was $193.xx but then tried to charge me 9.75%tn tax
A little finagling saved $25 bucks.
Sure it might show up a day later but...



Everywhere else on the net seemed to be around $229+