Topic: Jack Research Help Needed

[Sluggo]

My jack is original to the car. It is bent from the car apparently being jacked up incorrectly unfortunately.


Car is 13E build date jack is a 9D. San Jose car.


I'll get the measurement next time I'm out in the garage. Here's some pics.

[Carl]

Much appreciated Herr Dark Overlord,  its a nice late-ish '69 production piece with the u-shaped end blocks (April '69), so any jacks before that should be the U-blocks.  If you could let me know the length of that bottom leg, it would be highly appreciated.  So far I've gotten reports of one original small and two original large jacks.

  Carl

[Sluggo]

Much appreciated Herr Dark Overlord,  its a nice late-ish '69 production piece with the u-shaped end blocks (April '69), so any jacks before that should be the U-blocks.  If you could let me know the length of that bottom leg, it would be highly appreciated.  So far I've gotten reports of one original small and two original large jacks.

  Carl

5 3/4. Is the size an indicator of whether the car had a space saver or full size tire? The spare is one of the few parts my car was missing.

[Carl]

Thanks for the size, so far thats four large and one small. 
Ford didn't even bother to put a part number on them.  The assembly manual simply says "Jack."
I've heard pople talk about "6 cylinder jacks", the only comment that ever made sense was that they used different sized lug nuts, thus different sized lug wrench, thus different sized acme thread bolt head on the jack. 
The small and large jacks I have all have the same size bolt head on the Acme thread, so that isn't it.  It may just be that one vendor used smaller jacks, but you'd think someone would have mentioned it in the last 40 some years of history of the '70s.

  Carl

[Bob Gaines]

Thanks for the size, so far thats four large and one small. 
Ford didn't even bother to put a part number on them.  The assembly manual simply says "Jack."
I've heard pople talk about "6 cylinder jacks", the only comment that ever made sense was that they used different sized lug nuts, thus different sized lug wrench, thus different sized acme thread bolt head on the jack. 
The small and large jacks I have all have the same size bolt head on the Acme thread, so that isn't it.  It may just be that one vendor used smaller jacks, but you'd think someone would have mentioned it in the last 40 some years of history of the '70s.

  Carl

Carl , I don't think the shorter / longer jack had anything to do with wether the Mustang had a space saver or not. The early 65/66 Shelby's used the small /short jacks and all of the later 67-70 Shelby's used the the larger /longer jacks. Since I had observed the  distinct sizes in the Shelby's I had come to the conclusion that the shorter jacks were used on the shorter body style of the 65/66 and when the the larger heavier 67-70 body style came out the larger jack was needed. Not 100% sure if this is the reason or not. I have also observed both styles of the U shaped or solid block style jack are in both the shorter and longer length jacks. Just thought I would share some of my observations and theories to further the discussion. Bob

[Carl]

Much appreciated, Bob.  The "small" jack siting on my workbench is dated 9K23, so its at least period correct for a '70, I'm starting to wonder.  It has the Patent Number stamped into the base, square end blocks, cross indented flip top, and 1/2-10 Acme threaded rod, which are all correct for the '70s.  Unfortunately, the jack sitting next to it has all the same pieces, its just that the pieces that make up the jack are longer, each by 1".

  Carl

[Bob Gaines]

Much appreciated, Bob.  The "small" jack siting on my workbench is dated 9K23, so its at least period correct for a '70, I'm starting to wonder.  It has the Patent Number stamped into the base, square end blocks, cross indented flip top, and 1/2-10 Acme threaded rod, which are all correct for the '70s.  Unfortunately, the jack sitting next to it has all the same pieces, its just that the pieces that make up the jack are longer, each by 1".

  Carl

Carl, like I had said I was only using the Shelby car's as my research base as that is my field of interest. I can just vouch for what was used on that category of car for each year and not for the other varieties.  Interestingly The ones with date codes are only a very small percentage of the ones I have seen or what I presently have.  Based on that I can only conclude that there are way more jacks without date codes then ones that do . That is a shame because it would certainly help rule out various usage. I have also noticed a random usage of fine vs. course thread usage as if it was a mfg thing opposed to any specific time. I used to think the thread size was a early late variation but have since seen the course thread used on early cars and vice versa so I had to modify my thinking on that theory. I think the thread on the screw is a mfg variation that may indicate the particular plant and the jacks that were used by that particular plant during a particular time.  Unfortunately many of the jacks I have acquired were taken at swap meets etc. and the providence of their origin has been lost to me. I too have a number that are physically identical but different in size. Only a small number of them have date codes short and long so I can not see a pattern in that aspect. This is a evolving understanding process for me. Just a few more observations and opinions for the discussion. Bob

[J_Speegle]

Carl I think the research needs to make sure that you investigate the 69 and the 70's separately as well as assembly plants. Also the 6 cylinder jack thing does not work for 70 since that was the first year they stopped doing the different bolt patten and such as a cost saving measure..............Just a thought

Would add in some of the jacks I have but can not be certain that they are original to a specific car and it might just muddy the waters

[Carl]

Jeff,

  I agree on seperating the '69s and '70s, which is where the u-shaped end blocks helps.  Every '69 I've had identified as original had the u-shaped blocks, every '70 had the square block shaped end blocks.  I have a couple that aren't date coded, but those interestingly als don't have the patent number.
  I agree that for '69 and '70, they all (6's and 8's) used the same size lug nut, which takes away any sense for 6 cylinder jacks versus 8 cylinder jacks.  Like I said, the assembly manual simply calls out "jack", the only value is that it is supposed to be extended 8" when placed in the trunk.  MPC also doesn't distinguish.
  At present, I just want to answer small versus large, or if it doesn't matter.

Bob,

  I appreciated the Shelby focus of your response, and have read with interest the differences between wheel styles (and resultant lug nut variations) and the effect on jacks that resulted.  For '69 (and the semi '70s) my understanding was standard '69 jack for all (unlike earlier cars), so any size information could be helpful.

  Carl

[Sluggo]

See what you made me do Carl?..............


I fixed the jack and gave it a new paint job. Probably not dead nuts but good enough.
I'm also repopping the sticker since there was enough left of it to copy. The lettering is very very close and the size and shape is dead nuts. I'll print it on the laser at work on some adhesive backed label paper and stick it when I get home. There is a slight black boarder around it which is simply a cutting guide. The cut will be inside this line.

[Carl]

I beg forgiveness!
I keep getting while-I'm-at-it-itis, ever since I bought a mini-lathe I keep looking for little projects to try.  I bought the lathe when I had to make some rivets for my top frame, its been downhill (but enjoyable) ever since.  The jack rivets were a challenge since the rivets have the little "T"'s in a depression on the heads.
The challenge this weekend was that my 1/2-10 Acme tap did a really nice job cutting threads in the new end block, but the jack screw won't thread.  I'm suspicious of the Chinese tap I bought, but will take some measurements tomorrow.  Thread pitch, diameter, etc, are the same on the tap and jack screw, just one more challenge before re-assembly.

  Carl