70-81 F Body Backdrive Linkage
1970-81 Camaro and Firebird Gearshift Lock Out System
The manual transmission back drive linkage serves a few purposes. First it puts the steering column lever in the proper location to take out and insert the key. Secondly you can't take the key out of the switch, making it a safety device. Thirdly it turns the back-up lights on when reverse is selected with the gear shift. Fourthly it locks the shifter in reverse with the key out. making it an anti theft device.
The 1970-81 F Body cars spanning 11 or 12 years, had some changes and options that effected the different parts of this system. Start with transmission options, not only did you have 3 speed or 4 speed, you also had Saginaw, Muncie and Super T10 4 speeds.
Unless the car you own was serviced at a dealership it's whole life, chances are some if not all of the linkage has been taken off and discarded. And I've spent years trying to decipher all the different part numbers listed, in all the different parts catalogs.
This is a list is from ONE Chevrolet parts book (September 1980 Parts Catalog 10). In this ONE catalog there can be found 5 different part numbers for the lower rod (Swivel to transmission lever), 4 different upper rods (Swivel to steering column lever), 3 levers and 3 support brackets.
Group 4.035 Lower Lock Rods
3975603 (Saginaw)
4.035 ROD, Transmission control Lower lock NOTE 2: Use with reverse position left and up.
76 F (1st Design) (Chevy Parts Books)
378244 (Saginaw)
4.035 ROD, Transmission control Lower lock NOTE 1: Use with reverse position left and down.
76-78 F (M20) (2nd Design) (Chevy Parts Books)
473071 (Saginaw)
4.035 ROD, Transmission control Lower lock
78-80 F (M20) (Chevy Parts Books)
493453
4.035 ROD, Transmission control Lower lock
77 F (M21) (Chevy Parts Books)
75 ALL F/4 Spd. (exc. 350) (Pontiac Parts Books)
473072
4.035 ROD, Transmission control Lower lock
78-81 F (M21, M24) (Chevy Parts Books)
479628
4.035 ROD, Transmission control Lower lock
72-75 F/350 4 Spd. (Pontiac Parts Books)
3975618
4.035 ROD, Transmission control Lower lock
70-71 F/8 4 Spd. (Pontiac Parts Books)
72-74 ALL F/4 Spd. (exc. 350)(Pontiac Parts Books)
Group 4.035 Upper Lock Rods
3975607
4.035 ROD, Transmission control upper lock
76-77 F (M20) (Chevy Parts Books)
72-75 ALL F/350 4 Spd. (Pontiac Parts Books)
473065 (Have)(Saginaw)
4.035 ROD, Transmission control upper lock
78-80 F (M20) (Chevy Parts Books)
473067
4.035 ROD, Transmission control upper lock
78 F (M21) (2nd Design) (With Strut) (Chevy Parts Books)
79-81 F (M21, M24) (Chevy Parts Books)
3975624 (Muncie)
4.035 ROD, Transmission control upper lock
78 F (M21) (1st Design) (Without Strut) (Chevy Parts Books)
70-71 F/8 4 Spd. (Pontiac Parts Books)
72-75 ALL F/4 Spd. (exc. 350) (Pontiac Parts Books)
Group 4.040 Lever
473073 (Have)
4.040 LEVER, Control rod idler lever
78-81 F (M20, M21, M24)(Chevy Parts Books)
78-81 F (M15, M64) Chevy Parts Books)
3975623
4.040 LEVER, Lock rod idler
70-75 Camaro w/4-Spd. (exc. 2BC)Chevy Parts Books)
76-77 F (M21)(Chevy Parts Books)
3975606 (Have)(Saginaw)
4.040 LEVER, Lock rod idler
76-77 F (M20) (Chevy Parts Books)
76-78 F W/M.T.(M15)(Chevy Parts Books)
76-81 F (M15, M63)(Pontiac Parts Books)
76-78 F (M20)(Pontiac Parts Books)
Group 4.040 Support
473074
4.040 SUPPORT, Control rod idler lever
78-79 F W/M.T. (M15)
78-81 F (M20, M21, M24)(Chevy Parts Books)
78-79 F (M21) (2nd Design) (Pontiac Parts Books)(With Frame Strut)
80 F (M24)(Pontiac Parts Books)(With Frame Strut)
3975620 (Muncie)
4.040 SUPPORT, Control rod idler lever
70-75 Camaro w/4-Spd. (exc. 2BC) (Chevy Parts Books)
77 F W/M.T. (M21)(Chevy Parts Books)
3975604 (Saginaw)
4.040 SUPPORT, Control rod idler lever
70-75 Camaro w/Saginaw (3-Spd. and 4-Spd.)(Chevy Parts Books)
71 Camaro (3 Speed)(Chevy Parts Books)
76-77 F W/M.T. (M20)(M15)(Chevy Parts Books)
76-81 F (M15, M63)(Pontiac Parts Books)
76-79 F (M20)(Pontiac Parts Books)
Group 4.045 Lever
3975616
4.045 LEVER, Reverse
70-71 F/8 4 Spd. (Pontiac Parts Books)
72-74 ALL F/4 Spd. (exc. 350) (Pontiac Parts Books)
73-75 ALL F/4 Spd. (exc. 350) (Pontiac Parts Books)
3975610
4.045 LEVER, Reverse
72 ALL F/350 4 Spd. (Pontiac Parts Books)
492013
4.045 LEVER, Reverse
73-75 ALL F/350 4 Spd. (Pontiac Parts Books)
486392
4.045 LEVER, Reverse
75 ALL F/400 4 Spd. (Pontiac Parts Books)
Disclaimer:
Most parts that I describe and picture, have identification on or with them, others I can identify from other sources and deduction (educated guess).
Factory correct applications are your responsibility. GM made part and part # changes with no rhyme but a reason (no production interruptions at any cost).
Applications are for replacement parts that were available at the time of parts book printing, and when possible model specific assembly manuals.
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,
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!
