Tire Size Calibration, Shift Points and Tire Pressure Adjust(warnings/setpoints)

[Brutal_HO]

2.5% is surprisingly pretty linear +2MPH.

 

[kobra]

Awesome, thanks @Brutal_HO , I always appreciate you jumping in on these questions.

Are you saying then that this is really not big enough to worry about?
I'm not at all worried about my speedo, more worried about whether I am impacting performance enough to matter. I tow a pretty heavy 5th wheel at 16,800, but I do have an HO, so just trying to sort it all out.

Thanks again,
B

 

[Rockcrawlindude]

I can’t remember my stock tire size but my change was more like 5%. Wasn’t a life changing ordeal but the shift points are better now and the Speedo is accurate

 

[Brutal_HO]

Awesome, thanks @Brutal_HO , I always appreciate you jumping in on these questions.

Are you saying then that this is really not big enough to worry about?
I'm not at all worried about my speedo, more worried about whether I am impacting performance enough to matter. I tow a pretty heavy 5th wheel at 16,800, but I do have an HO, so just trying to sort it all out.

Thanks again,
B

I would say a 2.5% 2MPH difference will affect shift points marginally if at all. I guess it matters what (accurate) speed you typically tow at if you're in the best RPM range for fuel mileage and power, and whether you already have an AlfaOBD setup or access to one, and could easily change the tire size.

 

[kobra]

I would say a 2.5% 2MPH difference will affect shift points marginally if at all. I guess it matters what (accurate) speed you typically tow at if you're in the best RPM range for fuel mileage and power, and whether you already have an AlfaOBD setup or access to one, and could easily change the tire size.

Ok, thanks again.
Don't have anything like a programmer yet, so likely will leave it until I decide what I need. With the 3500, the TPMS alerts are not an issue, so the decision may be based on whether there are other things I may need to change that may justify the AlphaOBD.

B

 

[Brutal_HO]

Ok, thanks again.
Don't have anything like a programmer yet, so likely will leave it until I decide what I need. With the 3500, the TPMS alerts are not an issue, so the decision may be based on whether there are other things I may need to change that may justify the AlphaOBD.

B

Jimmy07 has reported that if you adjust the presets in the tire fill assist app, it will lower the TPMS thresholds.

Haven't had a chance to check that out as mine were already set with AlfaOBD when I did the tire size change.

 

[desert_wagon]

talked to my local dealership, they will do it as long as I purchase a 200.00 service contract. Hey let them take responsibility for screwing it up, if they do its covered. (tpms settings and tire size)

 

[JesseLackman]

Jimmy07 has reported that if you adjust the presets in the tire fill assist app, it will lower the TPMS thresholds.

Haven't had a chance to check that out as mine were already set with AlfaOBD when I did the tire size change.

Does that hold true with a 2020?

 

[jadmt]

Does that hold true with a 2020?

it only takes a minute to check..Some have reported it works others have said it did not work for them. Might be lucky. I would have tried it but I already used the procal to reset mine down to 45 psi and I needed it to calibrate the speedo.

 

[JHD1827]

I've gone from the OEM 285/60R20 to 295/70R18, which if I have it right is about 2.5% larger. Is this enough of a difference to make a difference?

BTW, I can't find the AEV Procal Snap in stock anywhere

Thanks!
B

I just ordered from AEV. Unless I'm overlooking it the "Does not work on Power Wagon" statement has also been removed from their site.

 

[jadmt]

I just ordered from AEV. Unless I'm overlooking it the "Does not work on Power Wagon" statement has also been removed from their site.

they have updated the software so it know works on new power wagons.

 

[HD5280]

it only takes a minute to check..Some have reported it works others have said it did not work for them. Might be lucky. I would have tried it but I already used the procal to reset mine down to 45 psi and I needed it to calibrate the speedo.

Mine TFA allows me to change the thresholds but seems to reset every time I turn the truck off. Not sure why it’s not working, but one thought is that it allows you to adjust them (up or down) just not below the 65psi minimum.

(to be clear, it lets you adjust below 65psi and appears to take, but just doesn’t stay programmed once truck is cycled.)

 

[AnthonyD1978]

Mine TFA allows me to change the thresholds but seems to reset every time I turn the truck off. Not sure why it’s not working, but one thought is that it allows you to adjust them (up or down) just not below the 65psi minimum.

(to be clear, it lets you adjust below 65psi and appears to take, but just doesn’t stay programmed once truck is cycled.)

I don't even have the TFA as an option on my truck. Not listed in any of my Uconnect settings. According to the manual it's an "if equipped" option. What option on the truck gives you TFA? My truck is fully loaded. Maybe power wagons don't get it?? @RamCares

 

[Rockcrawlindude]

I don't even have the TFA as an option on my truck. Not listed in any of my Uconnect settings. According to the manual it's an "if equipped" option. What option on the truck gives you TFA? My truck is fully loaded. Maybe power wagons don't get it?? @RamCares

Did you try to enable it in the cluster? I think you have to do that first

 

[Rockcrawlindude]

Mine TFA allows me to change the thresholds but seems to reset every time I turn the truck off. Not sure why it’s not working, but one thought is that it allows you to adjust them (up or down) just not below the 65psi minimum.

(to be clear, it lets you adjust below 65psi and appears to take, but just doesn’t stay programmed once truck is cycled.)

You have to delete the old presets. Try that. There is a button to access the presets

 

[AnthonyD1978]

Did you try to enable it in the cluster? I think you have to do that first

I think you have to enable it in the "Safety and Assist" screen of Uconnect. I don't have it listed as an option to enable. I have a weird feeling that certain combos of options don't get it.

 

[Rockcrawlindude]

I think you have to enable it in the "Safety and Assist" screen of Uconnect. I don't have it listed as an option to enable. I have a weird feeling that certain combos of options don't get it.

View attachment 12125

I’ll look when I get back to my truck. I could be wrong

 

[jadmt]

talked to my local dealership, they will do it as long as I purchase a 200.00 service contract. Hey let them take responsibility for screwing it up, if they do its covered. (tpms settings and tire size)

what is included in the $200 service contract? did you ever do this and did it work?

 

[jadmt]

I think you have to enable it in the "Safety and Assist" screen of Uconnect. I don't have it listed as an option to enable. I have a weird feeling that certain combos of options don't get it.

View attachment 12125

it is odd you don't have it. mine is a basic level 1 and it has it.

 

[AnthonyD1978]

it is odd you don't have it. mine is a basic level 1 and it has it.

The owners manual states that it's standard on the small 5" screen and "if equipped" for the 8" and 12" screens. Makes total sense