Hey everyone,

I'm new to tuning and working on my first custom car.

I have a 2005 Mercury Grand Marquis with a 4R70E transmission in it with no reverse.

I have a brand new 4R75W handy out of a 2003 police interceptor I want to put in. However, I understand that the Output speed sensor is different on the two transmission. From what I understand, the 4R75W has 6 holes in the ring gear to use as reference, whereas the 4R70E has 24. So if I install the 4R75W with my car's current flash, it will think it's moving 4x faster than it actually is.

How can I change the reference from 24 to 6 using my HP tuner?

Thanks in advance for any help!