I installed 4;10s and the speedometer is 10 MPH off. Understood! Asked dealer to flash computer for rear end change and he said he could not.
I have a predator and did flash it for the performance tunes but lost it when I went back to stock tune.
Need Help. What is the whole true story?
Thanks

 

Which Predator do you have? If it's the Diablo, just download the latest revision from the website if you havn't already. The gear change option is there, within the tunes i believe. Good luck!
Somewhatdamaged

 

Make sure you are using the latest version of DS Downloader - version 1,2,6,0.

The older version 1,0,1,0 will not allow the paramater to be changed after installation.

 

I have the latest at the time March 05 but without all the new revisions.
Are you saying the dealer does not have the capabilities to change it?
Thanks for your help.

 

That is correct - the dealer can not change it? Their software will not allow them to change the gear ratio as the change is not "EPA Approved" by Ford.

 

Thanks I will do it today. Shift points are all screwed up also with the 4:10.

 

Which Predator do you have - DiabloSport, C&L or Steeda. Which release revision are you using? What version of DS Downloader do you have? What is your CALID? What tune are you trying to install and calibrate for the 4.10 gears?