69 Jack questions

[Anthony C.]

What are the differences in jacks for 69 corvette? How big should the bottom foot pad be? Is there a difference from early 69 to late 69? Are they all the same configuration for all C 3's. I have been hearing a lot of different answers.

Thanks

[John C.]

Re: 69 Jack questions

Anthony

The attached photos show the difference between a 68/early69 jack and a later 69 one. I don't know when the switch occurred but the 69 jack in the photo is dated L 8 (December 68) and came in my December built car.

The 69 piece is much studier and the base is 5x9. The 68 jack has a 4x6 base and I wouldn't go near a car being held up by it.

John

[Anthony C.]

Re: 69 Jack questions

John

Thanks for the pictures just what i was looking for. One other question how would you tell a jack with a year date of 9 and month code is a 69 jack or a 79 jack is there a difference between these years?

[John C.]

Re: 69 Jack questions

Anthony

I don't know if 69 and 79 jacks are the same or not. I'll have to let some one else answer that part of your question.

John

[Joe L.]

Re: 69 Jack questions

John

Thanks for the pictures just what i was looking for. One other question how would you tell a jack with a year date of 9 and month code is a 69 jack or a 79 jack is there a difference between these years?

Anthony-----


The 1979 jack is the same as 1969. They MAY have gone to a 2 digit year code for 1979. This is sometimes the way this is dealt with. However, if they did not, then I would say there's no discernable difference between a 1969 and 1979 manufactured jack. It's possible that there was some nuance difference that occurred over the years, though. However, none that I know of.

[Lynn H.]

Re: 69 Jack questions

Joe and Anthony,
If I am not mistaken there are some minor differences between the jacks from 69 to 79. I have examples of both out in the garage (too cold out there tonight) and I will photograph and post them tomorrow. One thing that comes to mind is the "A" (for Ausco??) that is on the top of the 69 era jacks, I believe is not on the later C3 jacks, along with some other visual differences. As far as telling the difference by the dates, the TIM&JG that I have (2nd edition 1998) for the 78 and 79 cars states that 78 (and 77) jacks were dated with a three digit date code on the head of one of the rivets on the jack base (e.g.-743 indicates 43rd week of 1977). In 79 they went back to a date code being stamped on the crossmember on the cranking end and the code was then a number for the year, followed by a letter for the month, and then two digits for the day of the month (e.g.-9B20, being Feb 20, 1979). All of the 69 era jacks i have seen were only dated with month and year (e.g.-L8, being Dec 68).
Lynn

[Kenny C.]

Re: 69 Jack questions

I don't know about change over date but my Mid March 69 original jack is like the early version pictured.

[Grant W.]

Re: 69 Jack questions

John

Thanks for the pictures just what i was looking for. One other question how would you tell a jack with a year date of 9 and month code is a 69 jack or a 79 jack is there a difference between these years?

Hi Anthony
68 jacks are the same style as 67's. 68 with the stamp on the scissor bar. Early 69's are the same size and shape as 69 to 75. The dating on an 69 early jack will be dated on the scissor bar. 8 L
69 to 75 will have the stamp on the scissor again.
After 76 or 77 the jack became thinner in width and longer a bit. The dating is on the rivot for the 76 to 79 or 80. The 79 80 81 82 jack has the date stamp on the main square bar on top.
Hope this helps.
Grant

[Joe L.]

Re: 69 Jack questions

Joe and Anthony,
If I am not mistaken there are some minor differences between the jacks from 69 to 79. I have examples of both out in the garage (too cold out there tonight) and I will photograph and post them tomorrow. One thing that comes to mind is the "A" (for Ausco??) that is on the top of the 69 era jacks, I believe is not on the later C3 jacks, along with some other visual differences. As far as telling the difference by the dates, the TIM&JG that I have (2nd edition 1998) for the 78 and 79 cars states that 78 (and 77) jacks were dated with a three digit date code on the head of one of the rivets on the jack base (e.g.-743 indicates 43rd week of 1977). In 79 they went back to a date code being stamped on the crossmember on the cranking end and the code was then a number for the year, followed by a letter for the month, and then two digits for the day of the month (e.g.-9B20, being Feb 20, 1979). All of the 69 era jacks i have seen were only dated with month and year (e.g.-L8, being Dec 68).
Lynn

Lynn------


The jacks definitely changed between 1968 and 69. There may have been some carry-over of the 68 style jack into early 1969, but I can't say if or when such occurred.

However, the 1969 through 1979 jacks were all of the same part number----GM #3958710. Unless there were changes to the specifications for that part number, I don't understand how there could have been any substantial differences in the jacks over that period. Nuance differences like stampings, painting, etc. could well have varied but I just don't understand how there could have been significant differences in configuration.

For 1980 the jacks did change significantly AND the part number changed, too.

[Terry M.]

Re: 69 Jack questions

It is nuance differences, but I have noted the date stamp for 1973 and newer jacks are a different font (larger) that the 1969-1972 jacks. I have seen Corvette jacks with the date code stamped on one of the rivets, but I have not paid attention to what dates they are applicable. That date code on the rivet is a different format than the 1969-1972 code also, but again -- I didn't pay attention to the specifics.

[Lynn H.]

Re: 69 Jack questions

Lynn------


The jacks definitely changed between 1968 and 69. There may have been some carry-over of the 68 style jack into early 1969, but I can't say if or when such occurred.

However, the 1969 through 1979 jacks were all of the same part number----GM #3958710. Unless there were changes to the specifications for that part number, I don't understand how there could have been any substantial differences in the jacks over that period. Nuance differences like stampings, painting, etc. could well have varied but I just don't understand how there could have been significant differences in configuration.

For 1980 the jacks did change significantly AND the part number changed, too.

Joe,
I did not go through my parts books to check numbers (not sure if I have all the right books) last night, but was going from memory. Kind of forgot until just now, so here is pictures of a few of my jacks that I just took. It appears that the differences are fairly significant, so I like you am surprised that the part numbers would not have shown a change.
I have three jacks pictured. One is the what I am going to call the late 69 thru possibly 75 (I only say that from Grant Wongs' post and the date from one of the ones pictured).
The earlier jack appears to only have an A stamped on it. I do not see a number stamped in the immediate vicinity of the A for the year, although you can tell from the photos that I did not clean these up too well.
I have two of what I am going to call the 76 thru at least 78. From what I have read I am interpreting it that the 79 was the same, but dated differently (I am only assuming this). You can see from the photos that the upper portion of the jacks are significantly thinner, and I do not see the large A (for Ausco) on the top as I had mentioned earlier. One of these jacks (the one folded) is dated 650 (50th week 76?), and the other is dated 803 (3rd week 78?). These jacks are dated on the rivets as stated in the TIM&JG.
If the 80 jack is even different from these, I would be very interested in learning (possibly form some other readers), how so. I have an 80 I am working on and I thought these later jacks I have were correct for that car. If someone else could possibly post a picture of the 80 jack that would be great. I would also like to see an example of the 79 style date code if someone has it available. I do have another later jack with a handle incorporated , but I thought this one was C4. It also has a tag attached if I remember correctly, but I would have to go look. If so it may state the year on it.
Lynn

[Lynn H.]

Re: 69 Jack questions

Here is one more photo of the two later jacks. It would only let me put 4 in one post.
Lynn

[Joe L.]

Re: 69 Jack questions

Joe,
I did not go thought my parts books to check numbers (not sure if I have all the rights books) last night, but was going from memory. Kind of forgot until just now, so here is pictures of a few of my jacks that I just took. It appears that the differences are fairly significant, so I like you am surprised that the part numbers would not have shown a change.
I have three jacks pictured. One is the what I am going to call the late 69 thru possibly 75 (I only say that from Grant Wongs' post and the date from one of the ones pictured).
The earlier jack appears to only have an A stamped on it. I do not see a number stamped in the immediate vicinity of the A, although you can tell from the photos that I did not clean these up too well.
I have two of what I am going to call the 76 thru at least 78. From what I have read I am interpreting it that the 79 was the same, but dated differently (I am only assuming this). You can see from the photos that the upper portion of the jacks are significantly thinner, and I do not see the large A (for Ausco) on the top as I had mentioned earlier. One of these jacks (the one folded) is dated 650 (50th week 76?), and the other is dated 803 (3rd week 78?). These jacks are dated on the rivets as stated in the TIM&JG.
If the 80 jack is even different from these, I would be very interested in learning (possibly form some other readers), how so. I have an 80 I am working on and I thought these later jacks I have were correct for that car. If someone else could possibly post a picture of the 80 jack that would be great. I do have another later jack with a handle Incorporated , but I thought this one was C4. It also has a tag attached if I remember correctly, but I would have to go look. If so it may state the year on it.
Lynn

Lynn------


If the 2 jacks pictured on the right side of your photo are the jacks originally installed in 1976-78 Corvettes, then I think the factory must have been installing a jack that was other than the one specified in the AIM. I find it almost impossible to believe that the jack on the left side of the photo which looks like a GM #3958710 is of the same part number as the jacks on the right.

[Lynn H.]

Re: 69 Jack questions

Just doing a little sniffing, but do I smell a Restorer article here? I may possibly do some more research and attempt to step up to the plate. If I received a little encouragement, or a sense of interest. Maybe this is something that has already been covered. I do not remember seeing a article on these later C3 jacks, but maybe it has been done??
Input.....
Lynn

[Lynn H.]

Re: 69 Jack questions

Lynn------


If the 2 jacks pictured on the right side of your photo are the jacks originally installed in 1976-78 Corvettes, then I think the factory must have been installing a jack that was other than the one specified in the AIM. I find it almost impossible to believe that the jack on the left side of the photo which looks like a GM #3958710 is of the same part number as the jacks on the right.

Joe,
There is no question, that I personally removed all these jacks from Corvettes. I can only assume that they were original to the cars. I cannot even tell you with any certainty exactly what year cars I removed them from. There have been quite a few over the last 10 years or so. I think some input from the members who own and drive the 76-80 cars (particularly original owner cars).
Lynn