2004 48re Overdrive switch????

[Foster#17]

Hey guys, Ive been going to the track now for a few years and got my truck down to 12.7 @ 105 but it never shifts into overdrive at the same time every time down the track which makes it very difficult to have consistent times! It usually shifts way too late like its holding 3rd gear until it wont go any faster before it shifts to overdrive. What can I do to make this more consistent? I tried to do a manual overdrive switch by grounding the solenoid but it only works for about 5 seconds and sets a code and locks the truck in 3rd gear. Im Just not sure what I can do to make it more consistent??? :doh:

 

[Foster#17]

I got the switch to work! I had to remove the Transmission relay and cross pins 30 and 87 to prevent the codes from coming up!

 

[rockjeep73]

You can use a 33 ohm resistor from radio shack in between the switch and ground source. This will allow you to keep the trans relay in place and no codes.