Changing tire size in alfaobd

[moosem]

Ask @Jimmy07. He is the AlfaOBD authority.

Good idea! He helped me.

 

[cskindt]

Can anybody confirm that they have successfully calibrated their speedometer on a 2022 Model Year with Parksense using AlfaOBD?

There is something different about 2022’s. I know others have been successful on 19/20/21 model years.

I emailed AlfaOBD and they acknowledged that it is a know issue with no solution yet. That said, I may have just answered my own question! Lol.

However, there are lots of folks on here that have added larger tires to their 22 Laramies and Limiteds, which presumably have Parksense.

Is everyone just simply living with your speedometers being off? Or, are they just living with a bunch of disabled features and a dashboard lit up with warning lights?

I’ve also reached out to Rough Country and one other scanner tool company that I can’t think of… they both said the same thing, “..not compatible with Parksense“.

Does anybody have any insight on this?

I could only get to 2600 before my parksense disabled. With my 34's I'm only about 1 mph slow at 60 and 1.5 at 80.
I can live with that until there is a solution.

 

[moosem]

I could only get to 2600 before my parksense disabled. With my 34's I'm only about 1 mph slow at 60 and 1.5 at 80.
I can live with that until there is a solution.

I ended up getting it to work. It was operator error. I skipped the ABS initialization step. My tires are 33” and I ended up at 2567mm and my speedo is now spot on.

 

[cskindt]

I ended up getting it to work. It was operator error. I skipped the ABS initialization step. My tires are 33” and I ended up at 2567mm and my speedo is now spot on.

I'd like to be around 2640, but it disables parksense. Oh well, I'm close enough.

 

[moosem]

I'd like to be around 2640, but it disables parksense. Oh well, I'm close enough.

My tires are LT275/70/18. I used the theoretical circumference (2646mm) minus 3% and it’s perfect.

 

[ff1899]

I changed my tpms threshold and my tire size. I'm now getting a traction light all the time and a service trailer break message on start up. Any help?

 

[moosem]

I changed my tpms threshold and my tire size. I'm now getting a traction light all the time and a service trailer break message on start up. Any help?

After changing the tire settings, did you connect to the abs module and follow the steps of the abs initialization routine?

 

[ff1899]

After changing the tire settings, did you connect to the abs module and follow the steps of the abs initialization routine?

I did all the steps however the initialization itself for abs start button stayed gray and unable to press. The rest of the steps listed in it I did do

 

[moosem]

I did all the steps however the initialization itself for abs start button stayed gray and unable to press. The rest of the steps listed in it I did do

Try sending a DM to Jimmy07. He helped me when I had questions.

 

[Chris15228]

Went to 35s the other day. Have the bypass cable and AlphaOBD. 2021 Ram 1500 big horn black, 5.7. Have Saturn298's docs from google drive and have watched a handful of youtube.
If I understand all I've read on this thread and others:
1. being a 2021 I will probably need to re-do abs, clear codes and all that.
2. BFG KO2 are 34.5 thoretical, =108.3" circ., or 2750.8mm circ. rounding down and -3% for a rolling circ. means a good place to start is about 2660mm, however this is most likely higher than parksense will allow. If so, reduce mm circ until parksense works, see how far off speedo is. Either live with speedo off and parksense on, or speed o on and parksense off, unless i hit the 1:1,000,000 that it all works.

That about sum it up correctly?
Thanks

 

[Rivy.Ram33]

I did all the steps however the initialization itself for abs start button stayed gray and unable to press. The rest of the steps listed in it I did do

Hey brother you get an answer for this? Mines grayed out as well.

 

[frisby5]

I asked that question

Hey brother you get an answer for this? Mines grayed out as well.

A year ago and got no answer for the grey out

 

[bigal808]

I asked that question

A year ago and got no answer for the grey out

The option is greyed out but above that it gives instructions on what steps to take to do the initialization.

See video:

"AlfaOBD - Change your Tire Size to Correct Your Speedo on your RAM!!"

 

[frisby5]

The option is greyed out but above that it gives instructions on what steps to take to do the initialization.

See video:

"AlfaOBD - Change your Tire Size to Correct Your Speedo on your RAM!!"

I got the jscan app it was alot easier for me to change the tire size. I didnt feel like messing around with Alfa obd for tire size. I have both Apps now.