Unable to change axle ratio

[TexasRedMopar]

So, last week I swapped a from a 2.65 to a 3.07 differential in my 2013 Charger SXT, 3.6, 8hp45. Right away I got a P215C00 output shaft speed / wheel speed correlation code and the trans goes into limp mode. I tried my intune i1000 dcx and it would not allow me to change the axle ratio, stating "error reading axle ratio perameter". I reached out to Diablosport and was told they are unsure why it won't work after verifying it's up to date. I tried my local dealership but I'm not confident they completely understood what I was trying to do and after tinkering with it the tech gave up. So now I've tried a brand new intune i3 because once again the website states it will allow axle ratio changes on my specific vehicle. It arrived today, was updated, and I attempted to install a canned 91 octane tune. I witnessed it writing TCM files which is more than the dcx ever did. Once again I tried to adjust the axle ratio and I get "failure initializing or reading perameter. Please make sure vehicle is run position and the vehicle is not running". I have to admit this is extremely frustrating. Is the 2013 Charger 3.6 8 speed the only vehicle out there that can't change an axle ratio? It can't be that difficult. This new 3.07 came from a 2013 charger 3.6 8 speed awd car so it's possible to run this gear. Do I need a custom tune with the TCM files for the 3.07 gear?

[mikel]

Any 8 speed we have worked with didnt require any adjustment for gear change, so it seems this may be something specific to the early 13 V6 cars. I'll look into what we may be able to do. Can you post the info.xml file from the i3 drive here please?

[TexasRedMopar]

I put the factory tune back on. Do you want the file with the canned tune installed, or what's on the i3 unmarried?

[mikel]

the current info fie is fine.

[TexasRedMopar]

I believe you may be correct. There is a post on chargerforumz about the same issue. www.chargerforumz.com/threads/tcm-program.185312 I reached out to the original poster and he informed me that he was unable to resolve the issue. I'm really hoping this can be figured out.

[TexasRedMopar]

Well, I have played with this for the last two weeks and had to finally throw in the towel. I have spoken with a Chrysler tech who also writes custom tunes who is researching where this ratio is programmed. I installed the original 2.65 gears and everything is back to normal. I verified the shaft/wheel speeds with my scanner and both are reading the same now, so it's definitely a programming issue. Maybe one day this can be figured out and i can swap the 3.07 back in.

[mikel]

Do you have access to anything else that offers gear adjust options?

[TexasRedMopar]

Unfortunately I do not. The local dealership was unable to find anything so I'm hoping the Chrysler tech I've reached out to can figure it out. He tunes Hellcats and has access to all kinds of software. For all I know this could be in a body module somewhere. When the transmission goes into limp mode I get the ABS and transmission codes stored in the PCM, TCM, and body control module. Chrysler and their unending maze of modules is frustrating.