I have a 1993 Chevy 2500 4x4 that wont shift right.... When starting out it shift okay from 1st to 2nd but when it goes to shift into 3rd it drops the trans into 1st again and winds up the rpms... I just replaced the filter and trans fluid+a bottle of lucas... It doesnt have a throttle valve cable because its electronic and there is no electronic spark control between the valve cover and the throttle body... The truck was made with the esc in the computer... Help me please...

 

there are 2 shift solenoids bolted the the valve body, "A an B". common problem with the 4L80E