Rear Bumper Bolt Size

I have an install coming up this weekend for my 2000 TJ, this thread is AWESOME. Good advice on using a tap kit.
 
I have an install coming up this weekend for my 2000 TJ, this thread is AWESOME. Good advice on using a tap kit.
Only pay attention to the folks that said it is 12mm x 1.75. That change occurred about midway through the 97 model year for the bolts that go vertical into the frame to hold on the rear bumper.
The folks that said it was 7/16-14 are wrong but easily confused since the two are so close to each other.
7/16" is .4375"
12mm is .472
That means the 7/16" bolt would easily thread in and since both are coarse thread, they match up okay enough to sorta work.
 
@mrblaine

Are the front bumper bolts for an 03-06 also 12mm x 1.75?

I just noticed that I am missing one of the underside factory front bumper bolts (with torx head). Need to replace with the same or a hex head cap screw next trip to Ace or Fastenal.

The reason I ask is that I also just noticed that in the "What size if Front Bumper Bolt" thread the suggestion is to use 1/2-13, which just happens to be the closest SAE size to 12mm x 1.75. I'm wondering if its another case of close but not quite.
 
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The Mopar parts book says .437-14 which is a 7/16 14 pitch which is a course thread. Grade 5 or Grade 8 is what you want. This is the size of the bolt that goes in horizontally from the bumper into the frame from the rear side.
in case having a mixture of SAE and metric fasteners wasn't troublesome enough, now we're referring to SAE fasteners using decimals instead of fractions. lol.
 
in case having a mixture of SAE and metric fasteners wasn't troublesome enough, now we're referring to SAE fasteners using decimals instead of fractions. lol.
Yeah I never understood why the Mopar parts guide lists the decimal equivalent sizes unless their software just doesn't have the ability to work with fractions.
 
@mrblaine

Are the front bumper bolts for an 03-06 also 12mm x 1.75?

I just noticed that I am missing one of the underside factory front bumper bolts (with torx head). Need to replace with the same or a hex head cap screw next trip to Ace or Fastenal.

The reason I ask is that I also just noticed that in the "What size if Front Bumper Bolt" thread the suggestion is to use 1/2-13, which just happens to be the closest SAE size to 12mm x 1.75. I'm wondering if its another case of close but not quite.
The 3 locations on the front bumper are all 1/2-13 and always have been. The 2 behind the bumper for the sway bar are 10mm coarse thread and we use 3/8-16 in them with no issue. (not correct but they work)
 
Yeah I never understood why the Mopar parts guide lists the decimal equivalent sizes unless their software just doesn't have the ability to work with fractions.
I can figure those out. The ones I struggle with are when they list the sheet metal screws by their decimal equivalent and I don't have a good way to convert that to a #8, #10 etc. screw size.
 
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Yeah I never understood why the Mopar parts guide lists the decimal equivalent sizes unless their software just doesn't have the ability to work with fractions.

that's where I'd put my money.

Though it's entertaining to imagine that their engineers were just having too much trouble converting between fraction and decimal so just eliminated the need to :ROFLMAO:
 
This thread may be too old but I'm looking for these same bolts for a 97. I've tried 7/16 x 14 for sure and I think I tried a M12 x 1.75. Trying to find that bolt to confirm. Can someone look this up so I can be sure?
 
This thread may be too old but I'm looking for these same bolts for a 97. I've tried 7/16 x 14 for sure and I think I tried a M12 x 1.75. Trying to find that bolt to confirm. Can someone look this up so I can be sure?
97 is usually 1/2-13 for the rear underside bolts for the bumper.