How early can a dated part be to be correct

[Chester C.]

If a C2 part was dated 2 months before car was built would that be acceptable as per NCRS rules. What about 3 or 4 months.

[Don H.]

Re: How early can a dated part be to be correct

Six months is the rule, except glass which is 12 months

[Ralph E.]

Re: How early can a dated part be to be correct

Six months is the rule, except glass which is 12 months

On a early 67 build car would parts dated 66 be acceptable?

[Don H.]

Re: How early can a dated part be to be correct

yes,
if within 6 months of car build date, except glass which can be up to 12 months before build date.

[Ralph E.]

Re: How early can a dated part be to be correct

yes,
if within 6 months of car build date, except glass which can be up to 12 months before build date.

That explains why I have so many 66 parts on my very early 67

[Mark E.]

Re: How early can a dated part be to be correct

I'm no judging expert, but I've learned about documented exceptions to the six month rule. For example, apparently several 1970 cars have original engine blocks dated more than six months before final assembly.

So don't assume a part is not original just because of the six month rule. GM's ability to manage reasonable levels of inventory was terrible back in the day (it's not even that good today). They were the classic "batch and queue" manufacturing company, with very large and costly parts inventories. That causes component dates to be much earlier than final assembly.

That also enabled Toyota, with their efficient and high-quality Toyota Production System, to eat GM's lunch over the decades. But that's another story.

[Don H.]

Re: How early can a dated part be to be correct

Right. But NCRS needed to establish what it would consider "typical" production date of parts.
It chose 6 months out for parts except glass. Most parts dates will be within days or weeks of build date of the car.
The parameter selected by NCRS will encompass most instances but not all. I would never throw out a known original part because
it was dated outside the NCRS date parameter. Maybe that is what you said too.

[Mike E.]

Re: How early can a dated part be to be correct

Common sense often prevails with extremely original cars built shortly after long strikes, etc.

[Mark E.]

Re: How early can a dated part be to be correct

Right. But NCRS needed to establish what it would consider "typical" production date of parts.

The problem is that GM's "typical factory production" was all over the place for much of its history. Their processes were not in control, meaning they suffered a lot of variability due to poor standardized work, poor production control, poor inventory management, irregular part quality, training issues, frequent engineering changes, and so on.

The six month rule translates to two inventory turns per year. It would be interesting to reference an old GM annual report to see what level of inventory turns were reported. Even if two turns or more were achieved, that's an average so there would be periods of time they had more than six months of stock for a particular PN.

It's just hard to enforce a specific rule like six months, when we're dealing with GM's manufacturing capabilities from the 1950s - 1990s.

[Ken A.]

Re: How early can a dated part be to be correct

Yes, GM's management was "so poor" that they were creeping to a 50% market share & had record profits. The US Government told them to back off or they would be broken up.

[Richard M.]

Re: How early can a dated part be to be correct

What about tire air?

The air in my new 1959's tires was dated 11 years before it was installed. Would that get a deduct?

I found some NOS air on Ebay a few years ago but I lost the auction by a dollar.

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edit...Sorry guys, feeling a little silly today after I crunched my finger under a rubber mallet this morning.

[Mark E.]

Re: How early can a dated part be to be correct

And the ultimate consequence of GM's management direction over the decades: They steadily lost market share since the '70s to better managed companies, lost $ billions through the 1990s and 2000s, then ultimately went bankrupt in the 21st century. Today, GM would be extinct if Uncle Sam didn't bail them out.

Just one of many eye-opening examples of management's failure: In the 1980s, Roger Smith spent $45 billion on automaton technologies that didn't work. As a reference, that was more than the combined market value of Toyota, Nissan/Datsun, and Honda.

Don't get me wrong, I love the Corvette. But I'm relieved the GM logo isn't prominently displayed on it.

[Don H.]

Re: How early can a dated part be to be correct

Well, I think we're in agreement but not sure.
Getting all the back to OPs question, see post 2.

[Mark E.]

Re: How early can a dated part be to be correct

Getting all the back to OPs question, see post 2.

...and post 7.

[Edward J.]

Re: How early can a dated part be to be correct

Rich, If you were born in 59, You'll have all the hot air you'll ever Need just start blowing,That counts as being Correct , Right ???. being in Fla makes It even easier.