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JSCAN tire size reset - Is this video still accurate?

Delhux

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I’m planning to hook up my SGW cable and OBD module next week to update my tire size settings via JSCAN.

This video made it look pretty straight forward.



This will be my first time using JSCAN (or any programmer). I’m just curious if anyone who has used JSCAN to set their tire size recently, can confirm this video is still an accurate demonstration of how to do it.
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Jeeperjamie

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Seems pretty accurate. If your programming from larger tires make sure you measure how big they actually are mounted on your Jeep and plug that number in. All are not the same and just putting 37 or 35 in will not get it right, you will need to pull a tape. Other than that it's pretty straight forward and not hard to use Jscan.
 
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NateKY

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You may have to do it several times and keep dropping tires size. I have been arguing with mine for a week. At the moment my speedometer is 2 mph slower than GPS. I have had it within .5 mph but somehow it keeps changing without me changing it.
 

KevinC

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I agree with above posts.

You should be measuring with the tire on the Jeep. Measure from the ground up to centerline of hub. That is your rolling height, which will be less than the total height of the tire on Jeep.

Don't disconnect JScan after setting. Go and drive it and check with a stand alone GPS, not one hooked to Jeep via usb. You will probably have to make adjustments to get it right.

Mine also would change on itself randomly. It hasn't done it since I have it within .5mph. It is wise to check your speedo at least 2x month to make sure.

KevinC
 

Benbean66

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Just another that supports the above. I've adjusted mine several times since getting my 35's. I now have it within a half an MPH, so I feel satisfied. Tried one size up and one size down, and compared to GPS was a little off.
 

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cb4017

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That's the video I used and there were no surprises when I did mine.
I bought the adapter cable from Amazon and downloaded the app. I already had a cheap OBDII Bluetooth adapter (the blue one) from when I played with the Torque app.
Hooked it up and paid for the VIN license. No problems making the tire size change other than having to do it a few times.
As I recall the stock size in the computer was 31.8". I ended up with 32.8" for Rubicon 33" take offs to get the vehicle and GPS speed to match.
 

Kevin_D

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I agree with above posts.

You should be measuring with the tire on the Jeep. Measure from the ground up to centerline of hub.

KevinC
Be sure you double that dimension…

Kevin
 

FijiKid

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Wondering if process is same for manuals? Appreciate confirmation (hopefully). Ty!
 

Texops

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The one i have is super easy and has the small bypass and the app and i leave the dongle plugged in. You can opt for GPS automatically adjusting your tire size on it
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