Topic: Please read this before asking auto trans ??
in Forum: C3 Driveline Components
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Hot Springs, AR - USA
Joined: 4/24/2004
Posts: 3236
Vette(s): 69 Conv #'s match 427, TKO-600/.64, 3.36HD-Posi, HT, T/T, PS, PB, PW, SP, Leather, Comp XE264HR & Roller Rockers & Lifters, Air-Gap RPM intake, Holley St Av 770 VS, MSD 6AL+Dist+Blaster SS, K&N, Jet-Hot Hooker Side-Pipes, Steeroids, Al Rad, Spal Fans
this site will help you identify the auto transmission in your car....
http://www.nastyz28.com/transid.html

it also explains some of the basic usage info
THM400 - The THM400 was GM's Heavy-duty 3 speed transmission used from 1964 to 1990. Used on large displacement, high torque engines and engines with towing packages. Generally found in Chevy & GM trucks, cadilacs and large displacement engined, full size GM rear wheel drive cars.
THM350 - Medium duty 3 speed trans used from 1969 to 1989, Used in Buick, Olds, Pontiac and Chevrolet cars and Chevy & GMC light trucks until 1987. Generally used in straight and V6 and small block engines. Generally able to handle up to 400 foot pounds of torque.
THM700-R4 - 4 Speed transmission used in GM cars and light trucks with the 2.8, 3.1, 4.3, V6, Chevrolet built 305, 350 and 454 engines from 1982 to 1992.
Im posting this in response to a rash of questions about auto trannies which cannot be correctly answered without knowing model !!!
Even though it is a camaro site it is accurate..
I did find one difference in the manaul trans section.
The close ratio gearboxs generally came with 3.73+ gear ratio'ed cars. 3.55 geared and higher (numerically lower) cars used the wide ratio gearbox.
in 1969 an L-36 with a close ratio was offered with a 3.08 (econ),3.36 (std), 3.55 (perf) or 3.70 (spec)
what he said is true of SB cars, the l-46 350/350 was only offered with 3.70 and 4.11 on the close range m-21
http://www.nastyz28.com/transid.html

it also explains some of the basic usage info
THM400 - The THM400 was GM's Heavy-duty 3 speed transmission used from 1964 to 1990. Used on large displacement, high torque engines and engines with towing packages. Generally found in Chevy & GM trucks, cadilacs and large displacement engined, full size GM rear wheel drive cars.
THM350 - Medium duty 3 speed trans used from 1969 to 1989, Used in Buick, Olds, Pontiac and Chevrolet cars and Chevy & GMC light trucks until 1987. Generally used in straight and V6 and small block engines. Generally able to handle up to 400 foot pounds of torque.
THM700-R4 - 4 Speed transmission used in GM cars and light trucks with the 2.8, 3.1, 4.3, V6, Chevrolet built 305, 350 and 454 engines from 1982 to 1992.
Im posting this in response to a rash of questions about auto trannies which cannot be correctly answered without knowing model !!!
Even though it is a camaro site it is accurate..
I did find one difference in the manaul trans section.
The close ratio gearboxs generally came with 3.73+ gear ratio'ed cars. 3.55 geared and higher (numerically lower) cars used the wide ratio gearbox.
in 1969 an L-36 with a close ratio was offered with a 3.08 (econ),3.36 (std), 3.55 (perf) or 3.70 (spec)
what he said is true of SB cars, the l-46 350/350 was only offered with 3.70 and 4.11 on the close range m-21
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Hot Springs, AR - USA
Joined: 4/24/2004
Posts: 3236
Vette(s): 69 Conv #'s match 427, TKO-600/.64, 3.36HD-Posi, HT, T/T, PS, PB, PW, SP, Leather, Comp XE264HR & Roller Rockers & Lifters, Air-Gap RPM intake, Holley St Av 770 VS, MSD 6AL+Dist+Blaster SS, K&N, Jet-Hot Hooker Side-Pipes, Steeroids, Al Rad, Spal Fans
Im trying to build a "corvette for dummies" type reference link page..
smarter questions = smarter answers
smarter questions = smarter answers
That's a great idea. I will start saving things that may work, and send them to you.
|UPDATED|5/13/2004 6:22:15 AM (AZT)|/UPDATED|
|UPDATED|5/13/2004 6:22:15 AM (AZT)|/UPDATED|

Hot Springs, AR - USA
Joined: 4/24/2004
Posts: 3236
Vette(s): 69 Conv #'s match 427, TKO-600/.64, 3.36HD-Posi, HT, T/T, PS, PB, PW, SP, Leather, Comp XE264HR & Roller Rockers & Lifters, Air-Gap RPM intake, Holley St Av 770 VS, MSD 6AL+Dist+Blaster SS, K&N, Jet-Hot Hooker Side-Pipes, Steeroids, Al Rad, Spal Fans
cool
send them to cthulhu@staff.direclynx.net
send them to cthulhu@staff.direclynx.net

Hot Springs, AR - USA
Joined: 4/24/2004
Posts: 3236
Vette(s): 69 Conv #'s match 427, TKO-600/.64, 3.36HD-Posi, HT, T/T, PS, PB, PW, SP, Leather, Comp XE264HR & Roller Rockers & Lifters, Air-Gap RPM intake, Holley St Av 770 VS, MSD 6AL+Dist+Blaster SS, K&N, Jet-Hot Hooker Side-Pipes, Steeroids, Al Rad, Spal Fans
btw this is what i have so far... i still need to make it look good and such.. but im going o try to add diagrams and especially as much casting number info as I can.
http://www.direclynx.net/~cthulhu/corvette/vette_links.html
http://www.direclynx.net/~cthulhu/corvette/vette_links.html

Hot Springs, AR - USA
Joined: 4/24/2004
Posts: 3236
Vette(s): 69 Conv #'s match 427, TKO-600/.64, 3.36HD-Posi, HT, T/T, PS, PB, PW, SP, Leather, Comp XE264HR & Roller Rockers & Lifters, Air-Gap RPM intake, Holley St Av 770 VS, MSD 6AL+Dist+Blaster SS, K&N, Jet-Hot Hooker Side-Pipes, Steeroids, Al Rad, Spal Fans
oops, i posted too much info..
|UPDATED|5/14/2004 11:13:50 AM (AZT)|/UPDATED|
|UPDATED|5/14/2004 11:13:50 AM (AZT)|/UPDATED|
in Forum: C3 Driveline Components
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