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66 chevelle transmission option codes?

2.4K views 6 replies 5 participants last post by  DaleM  
#1 ·
What are the different option codes stamped on the cowl tag for the different transmissions available in 66 under option group 2? Thanks.
 
#2 · (Edited)
Hi Jim,

B, L, M, or Q

B = heavy duty 3-spd with floor mounted shifter. This was standard on the SS396 and an option only on the El Camino when ordered with a 396.

L = 4-spd.

M = Powerglide

Q has been found on some cars and the speculation is that it also is a 4-spd code, but is uncertain.

The absence of a code would indicate a standard column shifted 3-spd on any Chevelle other than a SS396. An SS396 should always have one of the 3 or 4 codes if built at one of the assembly plants that used these codes.

These are the ones I am aware of. I was wondering, though, if there might be an additional code for a 3-spd manual w/overdrive? Any reason for a body change to accommodate the overdrive?
 
#3 ·
Q has been found on some cars and the speculation is that it also is a 4-spd code, but is uncertain.
I have a 'Q' on my car. And resources I have found say that 'Q' was only used in '66 and '67 for M21 application specific. And also that this code was ONLY used from two plants, Atlanta and Kansas. Any input on this? :yes: