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Larger tires on OEM night edition wheels.

What’s Jscan and how can I do this? The low tire pressure warning is annoying… Also need to have my speedometer adjusted with the bigger tires if any tips on this!?
Jscan and Alpha OBD are both programmers you can use to make adjustments to the computers. I'm not a fan of messing with the truck's computers, so I stick with the most basic thing possible. Not just in function, but in what I'm adjusting.
The Alpha OBD seems to give you a little more functionality, but the Jscan was very easy to use, and it's cheap. They have a demo mode you can play with if you want to check it out. Look up Jscan on the app store (apple and Android). The icon looks something like this → 1735043451781.png
Mine says "OBD Jscan" under the logo, but that's on the Android market. I think the image above is the Apple version. The paid version, which gives you access to all the features is something like $30. It's cheap.
I'm not sure on Alpha's pricing or download, but pretty sure they have a demo version too.

With either, you'll need a security gateway bypass. The most popular here (and the one I used) is KAODtech. → https://www.kaodtech.com/product-page/security-module-bypass
And a way to connect to the OBDII port. Again, a popular option is Vgate, which is what I used. → 1735044031033.png

In all it was under $150 to be able to adjust my TPMS threshold, and adjust the tire size. The dealership was going to charge that as a minimum shop fee and now I can adjust a lot more stuff any time I want to (or to readjust the TPMS and tire size).
 
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Jscan and Alpha OBD are both programmers you can use to make adjustments to the computers. I'm not a fan of messing with the truck's computers, so I stick with the most basic thing possible. Not just in function, but in what I'm adjusting.
The Alpha OBD seems to give you a little more functionality, but the Jscan was very easy to use, and it's cheap. They have a demo mode you can play with if you want to check it out. Look up Jscan on the app store (apple and Android). The icon looks something like this → View attachment 80495
Mine says "OBD Jscan" under the logo, but that's on the Android market. I think the image above is the Apple version. The paid version, which gives you access to all the features is something like $30. It's cheap.
I'm not sure on Alpha's pricing or download, but pretty sure they have a demo version too.

With either, you'll need a security gateway bypass. The most popular here (and the one I used) is KODtech. → https://www.kaodtech.com/product-page/security-module-bypass
And a way to connect to the OBDII port. Again, a popular option is Vgate, which is what I used. → View attachment 80496

In all it was under $150 to be able to adjust my TPMS threshold, and adjust the tire size. The dealership was going to charge that as a minimum shop fee and now I can adjust a lot more stuff any time I want to (or to readjust the TPMS and tire size).

Man, thank you so much for this response!

I feel like I actually understand it and can act on it, very detailed, and much appreciated!

Merry Christmas!
 
You're welcome, I'm glad I could help.

Merry Christmas!!
 
Oh, and a side note about the Jscan and Vlinker. If you have multiple vehicles you can use them on those too. The Jscan will need you to purchase a "license" for each vehicle, but the Vlinker can be moved from vehicle to vehicle with no extra cost. It's not locked to a vehicle like the old Superchips or Bullydog devices that were popular 15-20 years ago.
 
Running Falken Wildpeak R/T, 37/11.50-20 on my stockers, 3.73, 2”level, Thuren frt sway bar, Bilstein 5100, AEV Procal Snap for speedo & TPMS. 45 frt, 30 rear psi tested using chalk method. No trimming , very MINOR rub on frt arms at full lock.
 

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I am curious to ask
With the bigger tires (35 or 37) and 3.73 gears with the diesel - how much did it change your gas mileage?
Did you notice any turning radius difference even with the factory 20" rims?

With my old truck - the back space change required a football field to make a U turn

If you guys are looking to do a lift - Here is my experiance when I did install one:
On my 2nd Gen 1500 (04 Ram 1500 4x4 with a Fabtech 6" lift) - I added the Lift and bigger tires - The lift was Fabtech and they used proprietary lower control arm bushing and tie rod ends - with that being said look at a kit that uses factory bushings and tie rods and such, this will save anyone some headache when locating parts especially when the company that is making the proprietary part goes out of business and then Fabtech wants to charge you for the new bracket with the Factory Bushings (which is what they should have done in the first place) and then you have to tear the truck apart for a third time to replace that bracket - I had replace the bracket a third time due to the powder coating failing because it was not prepped right - Luckily for them they replaced it under warranty (was told cosmetics were not covered)
 
2" Front Thuren Coils and 1" Rear Mid Rate Coils. 35" Falken AT4. 18mpg or better avg.
 
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