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Hi All, doing some spring cleaning and pulled my rear lower shock mounts out and have a question on the number and its meaning. The casting number is 3829265 66. I guess for use on both left and right sides. Is this a service replacement one part fits all? Or were the earlier shock mounts numbered like this?
Dan
1964 Red FI Coupe, DUNTOV '09
Drove the 64 over 5000 miles to three Regionals and the San Jose National, one dust storm and 40 lbs of bugs!
Dan, the right and left sides are physically different parts, designed to fit either the right or left spindle carrier.
Yup, they are different, depending on the milled flat on the shock rod bar. The angle on the strut rod bar in neutral vrs a slight angle on the standard production shock mount I now have. It looks like this was intended to be 'milled' and fit the side it was milled for. One casting fits all! Now think it's a service replacement for a one part that could be machined to fit both sides after original production parts wore out. There is a slight angle difference with the original part but very slight. Joe L. can tell us the gory details I bet!
Dan
1964 Red FI Coupe, DUNTOV '09
Drove the 64 over 5000 miles to three Regionals and the San Jose National, one dust storm and 40 lbs of bugs!
The numbers you are seeing are casting #s which happen to coincide with the part #'s. I believe all GM mounts, at least std suspension, had these numbers on them
The numbers you are seeing are casting #s which happen to coincide with the part #'s. I believe all GM mounts, at least std suspension, had these numbers on them
I don't remember the entire part numbers but the last three digits of the part number for this part for standard suspension were/are 929 LH and 930 RH.
As mentioned, the 265 and 266 are for cars equipped with optional HD F40/F41 suspension.
Thanks Michael, Dick, I removed the shock mounts because one had a slightly different angle to it for the shock. Left side had no part number, right side had 3829265 66 on it. It has no 'slant' and could be used for either side but was milled for the RH side. Just wondering when GM used/issued these? I do now have a nice set of the 929/930 castings which look great. Just curius what the 265/66 cast part was? Doesn't have full second cast number etc.
Dan
1964 Red FI Coupe, DUNTOV '09
Drove the 64 over 5000 miles to three Regionals and the San Jose National, one dust storm and 40 lbs of bugs!
Thanks Michael, Dick, I removed the shock mounts because one had a slightly different angle to it for the shock. Left side had no part number, right side had 3829265 66 on it. It has no 'slant' and could be used for either side but was milled for the RH side. Just wondering when GM used/issued these? I do now have a nice set of the 929/930 castings which look great. Just curius what the 265/66 cast part was? Doesn't have full second cast number etc.
Dan
Dan-----
The 3829265 and 3829266 shafts were used for all 1963-82 Corvettes with F-40, F-41 or FE-7 suspension.
The GM #3820929 and GM #3820930 were used for all 1963-82 Corvettes with standard suspension.
After about the mid-70's, the GM #3820929 and 3820930 were discontinued from SERVICE and replaced by the 3829265 and 3829266 for all Corvette SERVICE requirements. So, if a shaft or shafts was replaced after about that time, these are the ones that a Chevrolet dealer would have supplied.
Earlier PRODUCTION and SERVICE examples of the 3829265 and 3829266 have those part numbers appearing on them. Later SERVICE examples have no numbers, at all.
Thanks everyone! Yes the other side shock mount has no numbers, seems to match the 'angle' of the numbered one so at least they're a 'pair' They are slightly different from the correct 929/930 pair. Guess close counts in the parts pipeline!
Dan
1964 Red FI Coupe, DUNTOV '09
Drove the 64 over 5000 miles to three Regionals and the San Jose National, one dust storm and 40 lbs of bugs!
Dan, I think the offset where the shock attaches is different between the 929-30 and the 265-66 parts. It was discussed a while back (archives)and I remember something about clearance needed for the heave duty shock and trailing arm..
I've never really figured out why they didn't just use the '265/266' for all applications from the very beginning. It is true that in SERVICE the 265/266 cost a lot more than the 929/930 when both were available. However, I expect the reason for the difference was that there were a LOT more of the 929/930 being manufactured so the per unit cost was lower. Of course, there MAY also be some other NON-APPARENT difference between the 2 sets and that accounts for the difference in cost.
Hi All, doing some spring cleaning and pulled my rear lower shock mounts out and have a question on the number and its meaning. The casting number is 3829265 66. I guess for use on both left and right sides. Is this a service replacement one part fits all? Or were the earlier shock mounts numbered like this?
Dan
Originally posted by Dan Holstein (1440)
Thanks Michael, Dick, I removed the shock mounts because one had a slightly different angle to it for the shock. Left side had no part number, right side had 3829265 66 on it.
Dan,
I checked my rear lower shock mounts today ('67 L79), the RH is a NOS 3820930 (correct p/n for standard suspension) that I found a while back, but I was not sure about the LH which was cleaned up and reinstalled. It is just as you described yours, with the casting number "3829265...66"
I was also wondering why the "66" followed the LH casting number.
I checked my rear lower shock mounts today ('67 L79), the RH is a NOS 3820930 (correct p/n for standard suspension) that I found a while back, but I was not sure about the LH which was cleaned up and reinstalled. It is just as you described yours, with the casting number "3829265...66"
I was also wondering why the "66" followed the LH casting number.
Scott------
It's because the same forging was used for the 3829265 and 3829266 shafts. The forgings were just machined differently for either side. In the case of the 3820929 and 3820930 shafts, the forgings are different for either side.
It's because the same forging was used for the 3829265 and 3829266 shafts. The forgings were just machined differently for either side. In the case of the 3820929 and 3820930 shafts, the forgings are different for either side.
63/64 shock mount part number use
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