i have a 04 heritage i broke the stock trans case and replaced it with a trans out of a 99 or 00 i am getting a p0720 and p0722 code and would like to know how to fix it ive replaced the sensor but it didnt change anything

when the o/d light is flashing (for the first minute or so of driving) it shifts threw all gears i just doesnt shift at the right time
when the o/d light stops flashing it goes into a limp mode i guess where it wont shift out or 2nd till 70mph and then goes straight to o/d skipping 3rd

 

anyone????

 

come on over a hundred views and nobody has something to say

 

I don't remember enough about those differences to be sure, but I'll tell you what I think I remember.

I don't think the '00 trans had a turbine speed sensor. That would set a P0722 and not let the trans shift right. I seem to remember, but once again not sure, that the output speed sensor changed between '00 and '04. I think the '04 has more pulses per revolution. That means the PCM can't understand what it is seeing from the output speed sensor, so it calls it bad, stores a code, flashes the OD light, and goes to limp mode.

The short answer to all of this is that I don't think there is a way to make an older transmission work in a '04 truck. While it physically bolts in it won't ever work right.

You could modify the older trans, but it is going to take a lot of new rotating parts and a new case.

 

is there maybe a way to program the truck to see what is wants????

 

It's probably possible. I'm sure it would cost a lot less to buy a new transmission and have it installed than to write new software that can read what you have.