--^-- +1 with
@Sparky...
Once you have removed the Transmission Fluid Pan... Orient your view to where the
Shift Armature penetrates just inside of the Transmission Case. Fortunately ...
what you want to inspect is RIGHT THERE in Plain View. If you examine the attached Image... There is a
"Leaf Spring" that has the shape of an
"Angular Canoe" outlined in
RED ...with one end of it locking into a Hole in the under-body of the Transmission.
The other end that has an
"L" Shaped Bend that fits into the
Pawls of the PRNDL Bell Crank...
(Highlighted in (Yellow Dots). As the the Shift Lever and Park Neutral Switch get moved by the Driver working the Shifter Handle through the Cable and Cable Housing inside of the Vehicle...That
Long Flat Spring applies Constant Spring Pressure on each new (
Yellow Dot) position as the Shifter moves through various
PRNDL positions.
That "Leaf Spring" is Held In Place by an 8 (10?) MM Bolt, which pre-loads it and guarantees enough Constant and Reliable Pressure to keep the assigned
PRNDL in place under all driving conditions.
If you examine that Bolt and it has managed to loosen up... Gently Pop Off that
Shifter Cable Nylon Retention Bushing and then Manually feel around the "Leaf Spring" and see if it has become loose as you work the
PRNDL Lever through ALL of its Positions to ensure that the Pressure between the Spring and the Pawls are locking in solid.
Make certain to end up with the Shift Lever Armature in the Park Position before you re-attach the Nylon Bushing.
PLEASE REMEMBER TO CHOCK YOUR WHEELS BEFORE ATTEMPTING TO MOVE THE SHIFT LEVER OUT OF THE PARK POSITION.
If you discover that the
"Leaf Spring" has come loose... "Google" the information on the
4L60E Re-Build Procedures and determine how much "LIGHT" Torque is required to tighten it back down... and
apply some "Blue" Thread Locker in a VERY SMALL AMOUNT on the Bolt Threads...and then Tighten it down to the Precise required level of Torque. If it is NOT loose and does not require any repair... this would be a good time to replace your Transmission Filter-Fluid while you have the Case Removed. This is an Excellent Video on that subject: