4l60e not shifting into 3rd
it also has a couple of chewed up wires due to a rat problem so im thinking it could be some
Chewed up wires
Assuming it is not...
you need to
A. fix any and all wiring because that may fix the speedo issue and shifting issue
B. use a nice scanner to view live data and see what is being commanded
C. if A/B don't fix any issues, you need to do a line pressure check and we can go from there





