Manual Transmission

[Corvair1]

Hi fellows,
How can you tell if a manual transmission is a 4 speed?

[bbodie52]

Here is the transmission ID information from Clark's Corvair Parts...

http://www.corvair.com/user-cgi/catalog ... ge=TECH-13


http://www.corvairkid.com/64fccode.htm

Transmission code information

This code is located different depending on the transmission type:

Manual transmissions:
3-speed: Lower left front mounting boss
4-speed: Lower left side of case just forward of side cover
Automatic transmissions: Bottom center of transmission oil pan
The format of the code is $####%, where:

$ = the plant and type identifier:
R = Saginaw, MI 4-speed manual
S = Saginaw, MI 3-speed manual
T = Toledo, OH PowerGlide automatic
#### = the month and day of manufacture (year is assumed)
% = shift (D for day and N for night; Saginaw did not run a night shift so this is not included on manual transmissions)
Note: A capital "I" was used instead of a "1".

[miniman82]

How can you tell if a manual transmission is a 4 speed?

Does it shift into 4 gears?



Not sure I understand, was this a rhetorical question? Grab the shift shaft and see how many it's got, Or pull the cover and have a look at the gears inside.

[Corvair1]

We had it on the hoist today started it up and she sounded like a coffee grinder.... The sound came from the transmission. I have an other transmission but I have to identify it first. The numbers on the transmission that I can find is USE HYPOID LUBE, GM2 3858954, on the cover GM 3859956 A P. This transmission came off a 140.

[bbodie52]

Who would mate a 140 hp engine to a 3-speed manual transmission??? I've been around Corvairs since the early 1960s, and I've never even SEEN a 3-speed manual transmission (except in my 1956 Chevy 4-door).

If it has a backup light switch on the bottom of the transmission, it is a 4-speed.

...on the cover GM 3859956...

GM Part No. 3859956 is associated with 4.105 COVER - 1966-1969 CORVAIR 4 SPD. TRANS and with the 1966-1969 CORVAIR 3 SPD. TRANS. So that cover appears to be use on BOTH the 3-SPD and 4-SPD manual transmissions used in 1966-1969.

(Ref. Source: Pages 4-2P and 4-4P, 1960-1969 CORVAIR PARTS CATALOG, Revision No. 1, March 1970, Chevrolet Motor Division)