I am looking for help identifying the subject transmissions by CASTING NUMBER. According to my parts book, the transmission CASE p/n is the same for 57/60. I have an opportunity to pick up a spare transmission for my 57 Special but the case casting number is different. Can anyone provide information as to case casting numbers. Any info is appreciated.
1957/1958 Buick Special and 1959/1960 Buick LeSabre Sychromesh Transmissions.
- Thread starter 53ragtop
- Start date
For the most part ALL the trans. internals are the same across the years. A '57-'60 should have a 6 bolt top cover. These are the stronger of the two. Stay away from the 5 bolt top cover trans. they were not strong even for a straigh eight never mind a V-8.
Tom T.
Tom T.
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Tom
Appreciate your response. Yes this is a 6 bolt transmission. I have always thought that the pre 57 322 synchromesh transmissions (which were 6 bolt) were a “stouter” transmission than the one that was used in 57/60. Again, I thought that the transmission used on the Special/LeSabre’s with the 364 was a “new” light duty transmission. Is this an incorrect assumption?
So basically back to my original question are all of the synchromesh transmissions (cases in particular) installed behind 364’s interchangeable?
Thanks,
Gary
Appreciate your response. Yes this is a 6 bolt transmission. I have always thought that the pre 57 322 synchromesh transmissions (which were 6 bolt) were a “stouter” transmission than the one that was used in 57/60. Again, I thought that the transmission used on the Special/LeSabre’s with the 364 was a “new” light duty transmission. Is this an incorrect assumption?
So basically back to my original question are all of the synchromesh transmissions (cases in particular) installed behind 364’s interchangeable?
Thanks,
Gary
Gary,
Attached is the transmission write up from the '57 Buick Product School Manual that details the changes from '56 to '57. It indicates the '57 transmission is a beefed-up version of the '56 unit with different gear ratios. The Buick Master Parts Book shows many of the internal parts are the same from '56-60. Going by that data, the '57-60 units ought to be every bit as reliable as the earlier 6-bolt cover units.
Buick parts books printed around the time these cars were new show the '57-58 models used a case with GM part no 1174880. The '59-60 models show part no 1175493. Later books show the 1174880 for all '57-60 models.
The same cases were used on other GM cars of that era. Oldsmobile's parts book from '62 shows their 3-speed case for '57-62 full-size cars is the 1175493. Yet the '72 book shows the case for '57-64 cars to be a 1174880. The '62 Pontiac parts book shows their '57 model transmission case as a 1175493.
I could not dig up info on the casting numbers. The chances are low that the casting and part numbers are the same. The casting numbers aren't all that useful for identifying parts compared to using the part numbers.
The Buick part numbers for the complete transmission assemblies were different for every year '57-60. The '58 was different from the '57 at the rear yoke of the universal joint. The '58 u-joint yoke was built with missing splines so that the propeller shaft will only stab in one way. See attached page from the '58 Product School Manual. The '57 u-joint would have to be installed to use a later transmission in a '57 car.
I wondered about any differences in the '57-58 transmissions vs. the '59-60 transmissions due to the cable-operated clutch release found on the '57-58 cars. Early on, the Transmission Clutch Gear (input shaft) was a 1174861 in '57-58 and 1189193 in '59-60. Later books show the 1189193 for all four years.
Without comparing every part, the changes in the '59 and '60 transmissions appear to be minor items like internal washers and speedometer drive gears etc.
Attached is the transmission write up from the '57 Buick Product School Manual that details the changes from '56 to '57. It indicates the '57 transmission is a beefed-up version of the '56 unit with different gear ratios. The Buick Master Parts Book shows many of the internal parts are the same from '56-60. Going by that data, the '57-60 units ought to be every bit as reliable as the earlier 6-bolt cover units.
Buick parts books printed around the time these cars were new show the '57-58 models used a case with GM part no 1174880. The '59-60 models show part no 1175493. Later books show the 1174880 for all '57-60 models.
The same cases were used on other GM cars of that era. Oldsmobile's parts book from '62 shows their 3-speed case for '57-62 full-size cars is the 1175493. Yet the '72 book shows the case for '57-64 cars to be a 1174880. The '62 Pontiac parts book shows their '57 model transmission case as a 1175493.
I could not dig up info on the casting numbers. The chances are low that the casting and part numbers are the same. The casting numbers aren't all that useful for identifying parts compared to using the part numbers.
The Buick part numbers for the complete transmission assemblies were different for every year '57-60. The '58 was different from the '57 at the rear yoke of the universal joint. The '58 u-joint yoke was built with missing splines so that the propeller shaft will only stab in one way. See attached page from the '58 Product School Manual. The '57 u-joint would have to be installed to use a later transmission in a '57 car.
I wondered about any differences in the '57-58 transmissions vs. the '59-60 transmissions due to the cable-operated clutch release found on the '57-58 cars. Early on, the Transmission Clutch Gear (input shaft) was a 1174861 in '57-58 and 1189193 in '59-60. Later books show the 1189193 for all four years.
Without comparing every part, the changes in the '59 and '60 transmissions appear to be minor items like internal washers and speedometer drive gears etc.
Attachments
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TODD
THANK YOU for your very informative response. The reason that I was using casting numbers is that is about the only means of identification that the seller has offered other than a couple of pictures. The overall length (machined surface to machined surface) is the correct length. He says it came from a mid 50’s 364. Mid 50’s in my book would be a 322. The case number appears to be 1172137-3. Suspect the 3 is a pattern number. This does’t match up with anything that you came up with. The case number in my 57 is 1174880 which is supported by your information.
Since I don’t really need a transmission but rather just buying a spare, I am trying to make sure that this would in fact be a replacement.
Again thank you for your time and research. Much appreciated!
Gary
THANK YOU for your very informative response. The reason that I was using casting numbers is that is about the only means of identification that the seller has offered other than a couple of pictures. The overall length (machined surface to machined surface) is the correct length. He says it came from a mid 50’s 364. Mid 50’s in my book would be a 322. The case number appears to be 1172137-3. Suspect the 3 is a pattern number. This does’t match up with anything that you came up with. The case number in my 57 is 1174880 which is supported by your information.
Since I don’t really need a transmission but rather just buying a spare, I am trying to make sure that this would in fact be a replacement.
Again thank you for your time and research. Much appreciated!
Gary