Speedo Recal Suggestions

[kumplocke]

What size tires are you running? I was reading on the website that they can only go to 35in tires? Is that true for the 2022s also?

I'm running 35's I don't recall what tire sizes were available but at least two larger sizes were in the settings.

 

[Crusty old shellback]

Go Alphaobd AlfaOBD.
So much more you can do besides tire size and TPMS.
High beam lock out.
Speed limiter
Allow mirror reverse lights on Cail and Missi trucks
Add features you didnt pay for.
And more.

 

[Brewbud]

I don’t know what he’s talking about but there is a big difference in shifting and shift points after cal. It won’t hurt the transmission but It will shift way better after you correct the tire size.

Could be a difference between the ZF and 68rfe maybe? I don't remember a big difference for rpm shift points when I went to 37s with the 68rfe. I didn't drive it much uncalibrated though. Pretty much home from the tire shop and then calibrated it for the size of the tires with AlfaOBD.

 

[JamesEvan]

ditto I notice it with 35's so for sure would feel it on 37's.

Def noticing some sloppy downshifts (2nd-1st)

 

[2powerwagons]

Shift points changed on my truck when I went to 35s. I especially noticed it didn't want to downshift in hilly terrain. I ran it in tow/haul mode until I got the cable to recalibrate.
Back to normal afterwards.

 

[flan]

So if I feel like the shift points are too low and don’t mind the speedo being off a few mph, in theory I can program my truck to think it’s running 37’s instead of 35’s and the rpms would run out more before a shift occurring?

*im not going to but just theorizing..

 

[jadmt]

So if I feel like the shift points are too low and don’t mind the speedo being off a few mph, in theory I can program my truck to think it’s running 37’s instead of 35’s and the rpms would run out more before a shift occurring?

*im not going to but just theorizing..

i would be worried traction control would be impacted as well as odometer.

 

[Rockcrawlindude]

So if I feel like the shift points are too low and don’t mind the speedo being off a few mph, in theory I can program my truck to think it’s running 37’s instead of 35’s and the rpms would run out more before a shift occurring?

*im not going to but just theorizing..

I think, IMHO, a better solution to this hypothetical scenario would be to use tow/haul instead

 

[jadmt]

from AEV.
Will the ESP in my vehicle system be affected?
Yes, for the better. The ESP system uses vehicle speed along with individual sensors that measure acceleration both front-to-rear and side-to-side. ESP functions by calculating how much steering angle the user inputs and how fast the vehicle is going, and then calculates how much side-to-side acceleration should occur. If the side-to-side acceleration is less than what the ESP predicts, that means the vehicle is sliding and it will try to correct the situation by applying specific brakes at each wheel and/or reducing throttle.

If the tire size and gear ratio values are incorrect, the calculations the ESP system processes will also be incorrect. This can cause the ESP system to trigger at the wrong time, which at best can be annoying and if it happens at the wrong time (or doesn’t happen when it should) can be dangerous. Lifted vehicles are more prone to inadvertent ESP activation, because the speedometer is wrong. The ProCal SNAP will allow you to fix this issue so your ESP can function properly.

 

[PMHQ]

Go Alphaobd.
So much more you can do besides tire size and TPMS.
High beam lock out.
Speed limiter
Allow mirror reverse lights on Cail and Missi trucks
Add features you didnt pay for.
And more.

I thought about it...Just scared because I hear you can really Fk up your truck...I don't know what I need either to get it to work...I have a Mac computer and an Android phone...Also is there wiring to do/harnesses etc? The menu looked complicated to me from what I saw....I am not extremely techy....I may need to look into it again or pay someone to do it...

 

[Crusty old shellback]

I use a windows laptop. The wire harness is the security bypass cable. Simple to install once you've done it and figured it out. Just remove the lower panel from under the steering wheel and it's easier to get up into the blocks.

There are a lot of videos on youtube that can walk you thru things. Charlies pages or something like that is one I found and used.

First time you connect in, before you do anything else, is read the setup and save the file onto your computer. Then it's easy to reload if needed.

When you change tire size, there are several things you have to do afterwards to reset the system and clear the fault codes. I posted the write up in the ALPHAOBD AlfaOBD thread. But it's also on the youtube video.

And there are a bunch of people on here who have done it and can help walk you thru it if you have issues.

 

[PMHQ]

OK---Found out my truck will be here in 3 to 7 days at the dealer...Nice! I did buy the AlphaOBD AlfaOBD App, The necessary cables and the MX+ Module so that I can adjust the things I need (Tire Size/TPMS)...So all I need is to get the 4 digit PIN when I pick up my truck, am I correct? I already downloaded the APP and the other parts will be here in 5 days...I also have on Backorder, the AEV Procal Snap from CJC, and they told me that they will get them in January....I will probably just keep it in case I ever need it for something in the future....I am a bit nervous about doing the AlphaOBD AlfaOBD thing, but the install looks pretty easy. I will disconnect it when I am done changing the TPMS/Tire Size and stick it in a drawer so that I do not need to worry about the Service people seeing it... If anyone lives in NorCal or Western Nevada (Near Carson City) that has done this already that can help me with it, that would be awesome...Thanks for the info and sharing!

 

[Crusty old shellback]

You do not need the PIN anymore. Did my 21 without it.

 

[PMHQ]

You do not need the PIN anymore. Did my 21 without it.

Well, that just makes it even easier! Thanks for the input!

 

[JamesEvan]

So ran through AlphaOBD AlfaOBD Pressure Threshold/Tire Size procedures today and everything worked and speed is spot on, but when running through the tire size I was unable to do the ABS Initialization. I was connected and brake dash indicators were present/flashing, but Start/Stop for the procedure were grayed out and not selectable so moved on to ECU Ini + Fault Clearing. Just a little concerned as I was not able to do that piece, any thoughts?

 

[Brutal_HO]

I'm running 35's I don't recall what tire sizes were available but at least two larger sizes were in the settings.

Those are just predefined tires. You can also just put the size in cm directly.

 

[2powerwagons]

So ran through AlphaOBD Pressure Threshold/Tire Size procedures today and everything worked and speed is spot on, but when running through the tire size I was unable to do the ABS Initialization. I was connected and brake dash indicators were present/flashing, but Start/Stop for the procedure were grayed out and not selectable so moved on to ECU Ini + Fault Clearing. Just a little concerned as I was not able to do that piece, any thoughts?

That's odd. You sure you actually connected to the ABS module? The connection might have failed and you didn't notice .

 

[JamesEvan]

That's odd. You sure you actually connected to the ABS module? The connection might have failed and you didn't notice .

Yeah it was connected, but just couldn't start the procedure.

 

[kumplocke]

Those are just predefined tires. You can also just put the size in cm directly.

What? I didn't see that option. I am 1 mph off so maybe I'll try to fix it.

 

[JamesEvan]

Yeah it was connected, but just couldn't start the procedure.

Spoke with AlphaOBD AlfaOBD and ABS Initialization procedure is not runnable (hence greyed), you just need to follow the instructions displayed.