STEP #10: 2.7" OVERDRIVE SERVO (if applicable). To remove the OD Servo (see the CPD Drawing for the bore location) the valve body must be removed before hand. When you remove the main controls, you will find a hole in the case next the OD servo bore. The hole goes through to the barrel of the transmission where you will see the OD band. If you remove the OD Servo and do not anchor or hold the OD band, it can move when you attempt to re-install the OD servo. If this occurs, you will not have access to the Overdrive gear (4th).
BEFORE you remove the OD servo, use the Rooster Comb Spring (the flat metal part with the roller on the end of it), p.n. 7E332, to wedge against the OD band. Install it into the hole next to the OD servo bore so that the roller is sticking out. Wedge it against the back of the OD band and the transmission case, but do not damage the Rooster Comb Spring. Remove the snap ring retaining the OD servo using small screwdrivers or snap ring pliers. Next, remove the OD servo from the bore. If you should hear/feel the OD band fall, do not panic. You can push up on the pocket once the OD servo is removed from the bore. You will quickly learn that when you push up on the pocket, the OD band moves and the hole on the side will no longer be visible. The tip of the OD servo must contact the
pocket (dimple) in the band.
While still holding the OD Band in place with the Rooster Comb Spring, install the new 2.7" OD servo (F75Z-7H188-AA) and the appropriate return spring based on your horsepower level. NOTE: The 2.7" OD Servo does not have the metal sleeve like the stock 2.5" OD servo. Simply place the NEW return spring p.n. F87Z-7F201-AA over the servo piston so it sits in the perch. Apply some fresh ATF to the rubber seal around the edge of the new servo, then install the 2.7" OD servo into it's bore. Be sure to install it so it does not enter on an angle.
In the bore you will notice two grooves. The snap ring (7384) must be installed in the second groove. To do this, it may be necessary to use a hydraulic jack, with a large deep socket to help hold the servo up into the bore while you install the retaining ring (see Reverse Servo). Place the large diameter deep socket (i.e.
1-1/16") on the tip of the jack mount and raise the jack height to reach the OD servo bottom. Then slowly increase the height until the second groove in the bore is visible. DO NOT over force the servo up into the bore with the hydraulic jack, or damage to the transmission could occur. Once the snap ring is installed, you can remove the Rooster Comb spring from the hole.
ADDITIONAL NOTES:
In Step #13, the "shifter roller" is the Rooster Comb Spring, p.n. 7E332. Obviously, it needs to be re-installed on the valve body. You can also use a screwdriver to perform this step.
You cannot use spring p.n. F3LY-7F201-A or the stock 2.5” OD servo spring with the 2.7" OD servo.