Pictures and Identification of GM Clutch release forks.

GM Clutch Release Forks

General Motors clutch forks can be specific to engine, car line and model year.
These parts can have a huge influence on linkage geometry and therefore on pedal effort.
I have a collection of used, original, and N.O.S. forks that I will try to identify and compare to each other.

Below, I have quick references to forks I've identified. Click on the links for more detailed descriptions and applications per GM part catalogs.

Collection of clutch forks
Some of these forks are interchangeable with small differences, others are totally unique.

Side View
This view shows the difference in the arm bends.

340278
340278
The "278" fork is 10 5/8" long from bearing tip to push rod pocket.
It has one through hole on each rail on the pocket end.

3737454
3737454
The "454" fork utilizes the 3738054 pin for lower push rod attachment.
It is the replacement part # for 55-60 Passenger cars.

3739043
3739043
The "043" Clutch release fork was used on55-63 Corvettes and some 65 Passenger cars.
It uses the part # 3738054 pin for push rod retention.

3788401
3788401
The "401"is the 1962-67 Chevy II fork,
and is used with the #3788383 and #3849309 bellhousings.

3820008
3820008
The "008" is a 1963-64 fork, used on certain Corvettes and Passenger cars.
It is 10 1/4" from bearing end to center of the push rod pocket.
It utilizes a special push rod that extends through a ball that is used as a pivot.

3860005
3860005
The "005"was used on Chevy Full sized (B-body) cars from 64-70.

3887177
3887177
The "177" fork is the replacement fork for 64-81 Corvettes.
It utilizes a pin for lower push rod retention.

3892632
3892632
The "632" release fork is 9 3/4" from the push rod pocket to tip of bearing end.
The push rod pocket is offset toward the ground with a hole for a spring in it.
The example I have is new and doesn't have any holes on the side rails.

9787069
9787069
The "069" clutch release was used on many Buick, Olds and Pontiacs from 1964-1972

14007356
The "356" fork is used in 1978-88 A or G body cars only.
They can only be used with bellhousings specific to A & G bodies of this era without modification.
Top: used 1980 fork
Bottom: reproduction fork

14066235
The "235" fork measures 10 1/2" from bearing end tip to center of push rod pocket.
It has a hole on the side rail for the return spring and one hole on the opposite side for a return spring bracket.

Disclaimer:
Factory correct applications are your responsibility. GM made part and part # changes with no rhyme but a reason (no production interruptions at any cost).
Application charts are for replacement parts that were available at the time of parts book printing.
My observations come from the parts I have in my collection or other reliable sources, your parts may differ.
If Factory correctness is your goal, do more research, join car clubs and forums and buy an assembly manual if one is available for your Project Car (you wont be sorry).
This is a fun and interesting part of the hobby!