Changing diff ratio in VZ SS - how can speedo be corrected?

[exec57l]

Hi Everyone

I am looking at fitting a 3.73 LS diff I bought for my 2006 VZ SS auto which came with a 3.07 diff ratio. The car is a 6L and has the 4L65e auto.

Can anyone tell me 100% if I can get the speedo corrected through a tune or if it has to be done another way? Been doing a bit of reading and there is a variety of answers from yes it can be done through the tune to no it has to be done through a Jaycar kit?

 

[axemurderer101]

I got mine done by holden but my car was a manual, autos might need shift points adjusted through a tune though.

 

[acarmody]

Hi Everyone

I am looking at fitting a 3.73 LS diff I bought for my 2006 VZ SS auto which came with a 3.07 diff ratio. The car is a 6L and has the 4L65e auto.

Can anyone tell me 100% if I can get the speedo corrected through a tune or if it has to be done another way? Been doing a bit of reading and there is a variety of answers from yes it can be done through the tune to no it has to be done through a Jaycar kit?

Anyone with a Tech2 can do it. But getting a good tune will help you get the most out of the change.

 

[caaf]

You could use Body Dignostics from Envyous Customs. That program can change the pulse count.

http://www.envyouscustoms.com/products/vt-vx-vy-vz-body-diagnostics/

 

[Trayner]

tech 2 or envyouscustoms software can do it , just have to change the PPK count . Not to sure with the auto thou if it would have to have the shift points changed or not .