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Interesting the 2.56 was not the standard rear. 3.23 was standard without A/C, but 3.08 was standard with A/C when the automatic transmission was used.
Thank you. I'm assuming this more than likely is not original to the car. It does seem to have a Posi in it though. I am thinking this rear was donated along with the frame from a Buick convertible.....
The codes 1 4 02 could translate to April 2nd 1971?
Thank you. I'm assuming this more than likely is not original to the car. It does seem to have a Posi in it though. I am thinking this rear was donated along with the frame from a Buick convertible.....
The codes 1 4 02 could translate to April 2nd 1971?
It's possible it could mean that. Not a bad guess, since the rear end prodution date (assuming original) is May 4. So, what is the scheduled production week? What does the body plate under the hood say for that? If it's something like 05B or C or 06A or something later, you may be correct in that assumption. If the body plate has an earlier date, then the rear couldn't have been built after the car was.
Posi would have to have been added later. Otherwise R3 would be the code. Buick was who built the rear. Not necessarily which brand of car it was going to. There are B code rears in Oldsmobiles, so it could be indiginous to the car. It kinda doesn't have all that much relevance, really.
It's possible it could mean that. Not a bad guess, since the rear end prodution date (assuming original) is May 4. So, what is the scheduled production week? What does the body plate under the hood say for that? If it's something like 05B or C or 06A or something later, you may be correct in that assumption. If the body plate has an earlier date, then the rear couldn't have been built after the car was.
Posi would have to have been added later. Otherwise R3 would be the code. Buick was who built the rear. Not necessarily which brand of car it was going to. There are B code rears in Oldsmobiles, so it could be indiginous to the car. It kinda doesn't have all that much relevance, really.
ahh thank you for that. But I’m assuming an R2 code not correct for a 71 442?
the code on the plate is
08D
not sure what translates to. Thank you for the time as I’m a newbie at GM as a whole!
If you look at the Information Manual page above and the 442 ordering information power train options, it shows the R2 2.56 open rear gears are an available option for the 442 with automatic (M40). If it were posi 2.56, it would be stamped R3.
08D? Wow, that's the last week of August. I'm not 100% sure if that would be August of 1970, or August of 1971. August 1970 is more likely, but without a difinitive dated component to work with at this point, who knows? The axle could have been built on May 4, 1970. Could make sense. I recall back then they typically took a couple weeks off in late July for "changeover" to the new model year, and started churning out new model year cars starting in early August. We would go on vacation during that changeover time somewhere, and about 3 weeks or so later, school would start again.
If you post the VIN and a pic of the body tag, it can be likely determined by VIN sequence and/or body number. If it were 1970, it was right before the big GM strike the middle of September, 1970 which lasted 67 days. My dad has us kids working for him during that 2+ month stint every weekend helping fix up an old rental house. I remember that fall really sucked. I couldn't wait for the strike to end, not just because my dad would go back to work, but because I wouldn't have to keep up with doing slave labor!
I can't remember in the strike year whether 1972 model year changeover was on time or not because it pushed back the 73 body styles that were supposed to be 72s. Changeovers usually set in stone about 2 months or more in advance.
That puts it as an early build car August of 1970
If the original VIN sticker is still on the drivers side door, that would also confirm the build date.
R2 is an Oldsmobile code. If the rear was originally from a Skylark it would have code LK
Decent chance it's the original 8.5 inch corporate 10 bolt rear for the car.
That puts it as an early build car August of 1970
If the original VIN sticker is still on the drivers side door, that would also confirm the build date.
R2 is an Oldsmobile code. If the rear was originally from a Skylark it would have code LK
Decent chance it's the original 8.5 inch corporate 10 bolt rear for the car.
That puts it as an early build car August of 1970
If the original VIN sticker is still on the drivers side door, that would also confirm the build date.
R2 is an Oldsmobile code. If the rear was originally from a Skylark it would have code LK
Decent chance it's the original 8.5 inch corporate 10 bolt rear for the car.
Agree on the early build.
Just because there's a B on the axle tube doesn't mean it is/was from a Skylark. I think it belongs with the car originally . Likely, but can't be necessarily proven. The May 4th built puts it very close to the 90 day window typical sub-components got built. It's a Buick build rear according to the PIM code block information (see above) but it was stamped for that particular car's application. At least that's how I interpret it. The B is for Buick, apparently. There's notes that say even though the R2 is there with the B spaced away from it, it's actually considered a 3 character code of R2B with the 3 numbers following that for the day of year build, then the shift number at the end of all that. I thought if it wasn't a Buick plant built rear, it might be an alpha code for the build year of 71 (70 being A, 71 being B, 72 being C, etc.) but the year thing got hammered when the VIN and body number puts the car being built in August 1970.
