Decoding information for '65 Greenbrier engines, transmissions, and differentials
The source for the information on this page is Chevrolet Technical Service Bulletin DR #690 (reissue), dated April 2, 1965. The information has been reproduced in other locations, including Bob Helt's The Classic Corvair and The Corvair Junkyard Primer.
Engine code information
This code is located on the top of the engine block, immediately forward of the alternator / oil filter adapter.
The format of the code is $####@@, where:
- $ = the plant identifier, which is always T, for Tonawanda, NY
- #### = the month and day of manufacture (year is assumed)
- @@ = type identifier:
- RS = 95 HP, manual transmission
- RU = 110 HP, manual transmission
- RV = 95 HP, automatic transmission
- RX = 110 HP, automatic transmission
Notes:
- The four type identifiers listed above were used in forward control engines only, probably to denote differences such as the oil filler tube location.
- A capital "I" was used instead of a "1".
Transmission code information
This code is located different depending on the transmission type:
- Manual transmissions:
- 3-speed: Left front mounting boss
- 4-speed: Lower left side of case just forward of side cover
Automatic transmissions: Forward right side 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".
Differential code information
This code is located on the lower-left side of the differential carrier housing.
The format of the code is $$####, where:
- $$ = the type identifier:
- AV = Corvair FC, 3.55:1 ratio, manual transmission
- AW = Corvair FC, 3.55:1 ratio, manual transmission, limited slip
- AX= Corvair FC, 3.55:1 ratio, automatic transmission
- AY = Corvair FC, 3.55:1 ratio, automatic transmission, limited slip
- #### = the month and day of manufacture (year is assumed)
Notes:
- Corvair differentials were built at the Buffalo, NY plant only.
- A capital "I" was used instead of a "1".