[TA455HO]

Originally Posted by Judge273

I'd say it's clear...part number and tag too. That's documentation!

That's the casting number on the outside of the drum. Often, but not always, different than the part number.

Consider something like the water pump for the 1971. Assembly part number is 9790522. But it's made up of several individual parts. Impeller, shaft, bearings, seals and the main housing. The main housing might have a casting number like 482138, but if you try to use that number to look it up you typically won't get anything.

One of the more extreme examples is a carb. We might know it as part number 7041267, but it is made up of a few individual castings, jets, float, etc.. Actual stocking part number would be different than that.

You get the idea. I just didn't want you chasing your tail any more than any of us might usually do. Part numbers can refer to one or more casting numbers. In the case of the brake drums it is a one to one relationship.

Oh, and if Lloyd or someone refers to their MPC they might come up with a drum part number for 1970 and 1971 of 3841176. So you might be inclined to think that must be the part number for the 3993560 casting number. Unfortunately, not the case as the part number 3841176 has a casting number of 3841177 as seen here - and that is a pretty penny for each rear drum.


http://www.oldsobsolete.com/products...m-nos-3841176/

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