Operation CHARM: Car repair manuals for everyone.

Band Apply Pin Check

Exc. Models CD and CL
1. Position band apply pin selector gauge J-21370-6, or equivalent, on transmission case over rear servo bore with hex nut on side of gage facing toward parking brake linkage, and smaller diameter end of pin gage, J-21370 or equivalent, in servo pin bore.

2. Secure gage with two 5/16 18 x 1 inch screws, torquing screws to 18 ft lbs. Ensure stepped gage pin is free to move up and down in both tool and servo pin bore and that stepped side of pin faces front of transmission case.

Identification ring is located on band lug end Or pin. Selecting proper pin is equivalent to adjusting band.

3. To determine proper size pin to use, apply 25 ft lbs. torque on hex nut on side of gage. This will cause lever on top of gage to depress stepped gage pin into servo pin bore, simulating actual operating conditions. Note relation of steps on gage pin and machined surface on top of gage and determine proper size pin as follows:

a. If machined surface on top of gage is even with or above upper step on gage pin, long pin with three rings is required.

b. If machined surface on top of gage is between upper and lower steps on gage pin, medium size pin with two rings is required.

c. If machined surface on top of gage is even with or below step on gage pin, short size pin with one ring is required.

4. If new pin is required, make note of size required and remove gage from transmission case.


Models CD & CL (Light Duty Trucks 80-82)






1. Attach band apply pin selection gage, J-21370-9 and J-21370-6 or equivalents, to transmission case with lever pivot pin to rear, securing with servo cover attaching bolts.

2. Tighten attaching screws finger tight and check freeness of selecting pin, then torque bolts to 15 ft lbs. and ensure pin does not bind.

3. Apply 25 ft lbs. torque to lever on tool J-21370-6. Selection of proper rear band apply pin is determined by relation of flat on tool J-21370-9 to flat machined area around hole on tool J-21370-6.

4. Before removing gaging tool, note proper band apply pin to be used
during assembly of transmission.