Part # help: What�s the difference between GM 3850786 and GM 3830786?

[Gary B.]

Thanks,


Gary

[Joe L.]

The ‘66 AIM, on UPC L72, B1, lists GM 3850786 for the two “retainers” (plastic straps, I think) that hold the radiator overflow hose to the fan shroud for the 427 engine. The ‘67 AIM lists GM 3830786 for those two retainers on UPC L36, A5. In the revision block in the ‘67 AIM it says “Was 3850786 retainer” with a revision date of 1-9-67. Does anyone know the difference between 3850786 and 3830786?


Could GM 3850786 actually be a typo and maybe it should have been 3830786 in the ‘66 AIM as well? I can find no description anywhere of GM 3850786.


Thanks,


Gary

Gary-------


I can't find any record of GM #3850386. If it ever existed it was never available in SERVICE. GM #3830786 did exist. It was discontinued without supersession in June, 1971.

I am virtually certain that it's just as you suspect: 3850786 was an incorrect number, probably a typo. Usually, such corrections in the AIM are done exactly the same way as actually replaced part numbers.

[Gary B.]

[Joe L.]

Joe,

Thanks. I wasn’t sure if typos in the AIM were eventually corrected without comment, or corrected with a revision note.

Gary

Gary------


A correction made at the initial edition of a model year AIM from a previous model year AIM is usually not noted with a revision or otherwise noted. A correction made subsequent to the initial edition of a model year AIM is usually noted as revision.

[Gary B.]

[Joe L.]

Joe,

In this case, the incorrect part number in the ‘66 AIM must have persisted into the initial ‘67 AIM, and then been discovered and revised in Jan 1967.

Gary

Gary------


I expect that's exactly what occurred. Something else that occurs is this: let's say that the part number was corrected effective with the initial edition of the 1967 AIM. Then, there would have been no obvious "clue" that the 1966 part number was incorrect. However, if one finds a part number for apparently the same part that is one digit difference in the later AIM (and, especially, if the different digit is not the last digit), then one can almost be assured that the previously shown part number is incorrect OR the later shown part number is incorrect. I've seen this happen many times.

In this case, we know the formerly shown part number is incorrect because I can find no record of it and I can find record of the later shown part number.

[Gary B.]