C-3 Jack

[D S.]

A friend has a jack he pulled out of his 1973 Corvette. It is stamped 1D08 or 1DO8 on the side riser. Is that April 1, 1978? Or 1968? My 1970-1972 JG seems to indicate that only two characters are date code stamps.

Thanks,
Scott

[Joe L.]

Re: C-3 Jack

Scott-----

Neither. The date code indicates April 8, 1971 or April 8, 1981.

[D S.]

Re: C-3 Jack

So, this date code system had a repeating dating system? How would that differentiate between the two dates for the purist who is wanting his/her Corvette jack to be correct for a '71 or an '81? Glad I have a '70 jack with a two character date code.

[Harmon C.]

Re: C-3 Jack

They changed the way they are dated to a rivet.

[D S.]

Re: C-3 Jack

I'm sorry but I'm lost. 1968 had 8A for January 1968, 1969 being 9A for January 1969, 0A for January 1970. So 1A isn't January 1971 and 2A isn't January 1972? I wish the 1970-1972 JG was more specific. Rivet?

[Dave S.]

Re: C-3 Jack

Scott,
I've only seen the letter/number dating system meaning there is a letter for the month and a digit for the year. A1 would be January 1971. It is not on the base but on the side arm. I'm only familiar with jacks up to 1972. Beyond that it may have changed.

[Terry M.]

Re: C-3 Jack

Dave & D Scott have the 1968-1972 jack dating system correct. I have observed that sometime in 1973 the size of the date font became larger, but the code remained the same. After that I know nothing.

[Reba W.]

Re: C-3 Jack

I have never seen the day in a jack date, only year and month. But like Dave, my knowledge ends at 1972. Later ones may be different.

[D S.]

Re: C-3 Jack

Thanks, Dave. Someone told the man with the 1D08 jack that it was a 1971 jack and I immediately went for my 4th Edition of the 1970-1972 JG Manual. It begins stating as an example that in 1969 it was a two character date as well as 1970 but stopped there. Since it was stated in the 1970-1972 JG I assumed the two character date stamping continued through 1972.

[Harmon C.]

Re: C-3 Jack

So, this date code system had a repeating dating system? How would that differentiate between the two dates for the purist who is wanting his/her Corvette jack to be correct for a '71 or an '81? Glad I have a '70 jack with a two character date code.

I Have seen jacks by 81 that are dated on a rivet not in the same place as a 71 jack. The shape may have changed also.

[Joe L.]

Re: C-3 Jack

A friend has a jack he pulled out of his 1973 Corvette. It is stamped 1D08 or 1DO8 on the side riser. Is that April 1, 1978? Or 1968? My 1970-1972 JG seems to indicate that only two characters are date code stamps.

Thanks,
Scott

Scott-----

The date code of 1D08 denotes April 8, 1971, April 8, 1981, April 8, 1991, or April 8, 2001. Period.

Could the date be April 8, 1971? As others have mentioned, the date coding on the 69-79 jack, GM #3958710, is usually just year and month. However, I have not seen every 3958710 ever made so I can't rule out that some used a different date coding system which included day.

However, as far as I can tell, the GM #3958710 jack ceased to be manufactured after about 1980 and was discontinued from SERVICE in March, 1981. So, certainly no 3958710 could have been manufactured in April, 1981 Consequently, if the jack is a GM #3958710, then the date on the jack you are referring to has to represent April 8, 1971.

If the jack is NOT a GM #3958710 AND it's actually a Corvette jack, then the date CANNOT be April 8, 1971. In that case it must be April 8, 1981, April 8, 1991, or April 8, 2001. However, in that case the jack has to be a 1980-82 GM #14016051 OR one of the C4 jacks. Although part numbers are usually not stamped on these jacks, neither the 14016051 or one of the C4 jacks is configured like the 3958710. The 14016051 became the 53-79 SERVICE jack in March, 1981.

So, once you determine which jack it is, determining whether the date is 1971 or some other year should be pretty easy.