66 Muncie differences 3880853/3880855

[Wayne M.]

Re: 66 Muncie differences 3880853/3880855

Ron, was just reading this post. I have a very original L36 with AZ code rear, 3.55, and a 3880853 tranny tag(orig). 82k mile car.

John -- is your car a '66 model ? If so, I would expect to see a trans sidecover tag "855", not an '853' with the AZ 3.55 rear diff.

But if it's a '67, then, yes, the '853' would be found on 3.55, 3.70 and 4.11 ratios.

[John R.]

Re: 66 Muncie differences 3880853/3880855

Wayne, yes it is a '67, guess I missed that. Thanks!

[Ronald L.]

Re: 66 Muncie differences 3880853/3880855

Wayne further back, I think we settled on a 853 tag for the L36 w/ 3.70 and green speedo gear - 1966.

[Wayne M.]

Re: 66 Muncie differences 3880853/3880855

Wayne further back, I think we settled on a 853 tag for the L36 w/ 3.70 and green speedo gear - 1966.

Ronald -- and that's still the case, as the thread dealt with 1966 models only (even though the '010' maincase trannys and the part # steel tag remained the same for 1967 with the same speedo DRIVE gear).

But when I saw John's recent post, I had to enquire what year his 3.55 car was, as at the factory, 1967 calls for NO red 21-tooth driven gear for the 3.55 ratio; the green 22-tooth gear for both 3.55 AND 3.70, and the ORANGE 25-tooth for 4.11. Therefore a '67 3.55 car would have the '853' tag (not the '855' of 1966).

[Ronald L.]

Re: 66 Muncie differences 3880853/3880855

Wayne, John, etc...

The point on this thread just struck me, given that the tag number was the same, but the drive gear was different...how did St Louis keep the separate as they would have to put a trans with a different drive gear into a 3.70 versus a 3.55?

Was it a paint or letter marking on the transmission?

[John H.]

Re: 66 Muncie differences 3880853/3880855

Wayne, John, etc...

The point on this thread just struck me, given that the tag number was the same, but the drive gear was different...how did St Louis keep the separate as they would have to put a trans with a different drive gear into a 3.70 versus a 3.55?

Was it a paint or letter marking on the transmission?

Ron -

Somewhere the transmission part numbers and associated drive and driven gears have been confused or mis-identified in the manuals. There was no such thing as two transmissions with different drive gears having the same transmission assembly part number. The O.D. of the drive gear on the output shaft was a discriminator at Muncie that changed the part number of the assembly, and the part number tag on the side cover was the only means of identifying the transmission at St. Louis.

[Ronald L.]

Re: 66 Muncie differences 3880853/3880855

John,

I might be getting a 1970 mixed up in this, but was there NOT a letter code painted on the top of the Muncies???

[John H.]

Re: 66 Muncie differences 3880853/3880855

John,

I might be getting a 1970 mixed up in this, but was there NOT a letter code painted on the top of the Muncies???

Not on midyear Muncies - dunno about the C3 era.

[Ronald L.]

Re: 66 Muncie differences 3880853/3880855

I'll see if I can get a picture, I am 99% sure by 1970 they had a letter code painted in thick paint on top...

[Terry M.]

Re: 66 Muncie differences 3880853/3880855

My 1970 has a two letter broadcast code in yellow on the top. WL I think, but don't hold me to that. The low mile 1972 ZR1 has the two letter code in yellow on the side of the transmission, but it is the only one I have seen on the side -- but I haven't seen all the 1970s or 1972.

[Ronald L.]

Re: 66 Muncie differences 3880853/3880855

I am sure I saw a black one. I need to go back through my pictures and the friends barn full of parts to verify the year, etc. I am sure it was Corvette specific as I have not seen this on any of the Norwood Camaro Muncie's for and of the years.

[Ronald L.]

Re: 66 Muncie differences 3880853/3880855

OK - confirmed, one of our fellow members Larry Shoup with a very original 70 has a TM inked on the top in black, where it was identified that TM represented a transmission destined for St Louis. How early was this inking- painting on the top started?

[Joe L.]

Re: 66 Muncie differences 3880853/3880855

OK - confirmed, one of our fellow members Larry Shoup with a very original 70 has a TM inked on the top in black, where it was identified that TM represented a transmission destined for St Louis. How early was this inking- painting on the top started?

Ronald------


There is no code inked on the top of my late 1969 Muncie.

Starting in 1971, the only thing the code could have denoted was whether the transmission was a wide ratio or close ratio. There was only one DRIVE gear used for all 1971+ Muncies. All speedometer calibration was done via DRIVEN gear and, in some cases adapter, both installed at St. Louis.

[Terry M.]

Re: 66 Muncie differences 3880853/3880855

OK - confirmed, one of our fellow members Larry Shoup with a very original 70 has a TM inked on the top in black, where it was identified that TM represented a transmission destined for St Louis. How early was this inking- painting on the top started?

My 1970 has A29 (January 29) on the trim tag.

[Ronald L.]

Re: 66 Muncie differences 3880853/3880855

I know we are pulling this thread in a different direction that where it started, but here is a bit of data...

Both 661 muncies

A P3C14A had a WD in black ink on the top LHS in letters about 1.5" high.

This one came from a 1973 vehicle 33Mxxxxxx

A P0D30A had a DJ in black ink on the top RHS in letters about an inch high.