Speedometer calibration with a 700R4 Trans

[6772owner]

If you have to change the drive gear (on the tailshaft) you have to remove the tailshaft housing so its best to drain it in my opinion. I have changed the driven gear several times without draining the trans, I just jack the rear up to put the fluid towards the front of the trans. You can also pitch it a little to the passenger side, this will give you minimal fluid lose, just top off the trans when finished.