Seat belt bolt, 11mm??

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my64fj40

my64fj40

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Hey guys.

I'm working on getting my 64 ready to pass inspection and apparently they want seat belts installed. :D

I found several threaded inserts on the tub for this, but couldn't get any sort of bolt to match up. I busted out the metric taps I got and the only one that fit was the 11mm. Am I missing something here, is this really 11mm? If so, what would be a source for an M11 bolt?
 
Seems I recently saw a mention here that they are actually sae bolts. They need to be grade 8 or something, and that makes it difficult for some japanese hillbilly dude to substitute a low tensile garden variety metric bolt from an old clothes dryer.
 
Yes, they're 11mm fine thread. Get them at the junkyard in any toyota and many other vehicles. Stay away from the f&^%ing torx fasteners. Most of the seatbelt bolts are heavily loctited, and the torx bit chews up the bolt head by the time the entire length of fine thread bolt is wrenched out.

But are belts really a legal necessity on a 1960's vehicle that was not legally required to have belts when new? If this is so, will the state compensate owners for the expense of adding seatbelts and reinforced mounting points?

Seems kinda overreaching that they can effectively junk a vehicle because it doesn't meet requirements that were not in effect on the date of manufacture.:hhmm:
 
Jim, IIRC, there's a webbed brace in the forward section of the rear wheelwells on both sides where the captive nuts for the outboard sides of the front belts go, so I think there were provisions for them even when they may have been shipped without.

I have a bin box full of these bolts if anyone needs some.;)
 
Yeah, I've seen the holes in the tub for belt mounts, even in 1964, but my point remains: The vehicle is not a passenger car, it's an MPV, and was not required to have seatbelts, padded dash, reverse lights, etc. when new.
Isn't stuff like this "grandfathered" as OK today?
 
7/16th NF

Japan4X4 said:
7/16nf
Click to expand...

This is true. I found out the long way... Its a simple 7/16th Fine thread bolt. Actually you can find this bolt everywhere the seatbelts attach to the body. My understanding is thats its a DOT requirement.

I also think its used on the driveshaft(s) as well.

:cheers:
 
It is 7/16-20UNF... and/or 11mmx1.25

7/16" =11mm (within .004")
1.25 pitch = 20.3TPI

Appears to be an oddball thread that works in either system.

The d-shaft bolts are 11mmx1.0.
 
wow, you guys just helped me tons!! I stripped my 78 40's roll bar bolts and thought I'm gonna search forever for a tap an bolts but this makes life alot easier! Steve
 
Seatbelts are NOT required in Texas if the vehicle did not originally come with them. Tell your inspection guy to READ his manual and stop FABRICATING rules. Bull****.
 
11x1.25 tap and die

:bang:well, was bolting the seatbelts back up after rust-bulleting the floor pans.......&:mad: cross threaded the blasted bolt:bang:of course the insert threads are screwed.......no :hhmm:problem, just need to get a 11X1.25 tap and die and chase threads:eek:the lowest price I can find is 68$ for just the tap...:crybaby:
when checking against a 7/16th NF tap that I have there is a bit of difference under a magnifying lens.......am compulsive enough to want to go with the original thread to keep things sorta standard and not have to try to figure out what goes where whenever I have to take them out again..........:hhmm:questions I have;
anyone have a cheaper source for these taps/dies?
does it make a difference?; there is just enough under the lens to make me :hhmm:wonder if when cranking down on the bolts I might break one off and then:bang::bang::bang:TIA

Lou
 
You can buy a M11X1.25 tap for $10.79 at mscdirect.com page 293. You can buy a Metric Hex M11X1.25 Rethreading Die for $10.91 on page 377.
 
This Thread is super old, but I wanted to chime in since I just had to rethread my seatbelt bolts and this helped. The M11 x 1.25 thread is in fact incorrect and is notably different than the 7/16-20 thread. The 1.25mm thread pitch gauge rocks back and forth on the seatbelt bolt, not able to fully seat.

For a short thread engagement, maybe like a nut of say a 8-10 mm thickness you might get away with it, and I am sure some have, but 7/16-20 fits like it's supposed to.

On our local forum Dave found the associated information for the bolt size:

eCFR — Code of Federal Regulations

a quote from the link, section F:

(f) Attachment hardware. A seat belt assembly shall include all hardware necessary for installation in a motor vehicle in accordance with SAE Recommended Practice J800c (1973) (incorporated by reference, see §571.5). However, seat belt assemblies designed for installation in motor vehicles equipped with seat belt assembly anchorages that do not require anchorage nuts, plates, or washers, need not have such hardware, but shall have 7/16-20 UNF-2A or 1/2-13 UNC-2A attachment bolts or equivalent metric hardware. The hardware shall be designed to prevent attachment bolts and other parts from becoming disengaged from the vehicle while in service. Reinforcing plates or washers furnished for universal floor, installations shall be of steel, free from burrs and sharp edges on the peripheral edges adjacent to the vehicle, at least 1.5 mm in thickness and at least 2580 mm2 in projected area. The distance between any edge of the plate and the edge of the bolt hole shall be at least 15 mm. Any corner shall be rounded to a radius of not less than 6 mm or cut so that no corner angle is less than 135° and no side is less than 6 mm in length.
 
I have no stake in this issue, however I find it interesting the Federal government specifies all its measurements in millimeters EXCEPT the actual bolt threads. I do note the phrase "or equivalent metric hardware." So............if there is no known exact metric equivalent to the 7/16 bolts including pitch, are the fittings deemed interchangeable with 11mm and some "slop" is permitted? And all this being safety-related.

Would be interesting to hear from a Toyota engineer as to whether Toyota used metric fittings for seat belt connections back then, and/or has switched to the 7/16 at some point in the past. Toyota did hang on to the JIS system past the international agreement to use ISO, and then finally relented to standardize their production with the rest of the world.
 
rover67 said:
This Thread is super old, but I wanted to chime in since I just had to rethread my seatbelt bolts and this helped. The M11 x 1.25 thread is in fact incorrect and is notably different than the 7/16-20 thread. The 1.25mm thread pitch gauge rocks back and forth on the seatbelt bolt, not able to fully seat.
...
Click to expand...

Agree, every Toyota seatbelt bolt that I have measured, a lot if them, were 7/16-20. That size nut, thread chaser, die, etc, thread right on, the metric does not. My understanding it's the only std size hardware used long term on Toyota's. One of the reasons given; the seatbelt bolts are application specific, so reduces the chance of the wrong hardware being used.
 
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Found 8 of these bolts in a ziplock. Wondering if anyone recognizes the head as Japanese? Pretty sure they are 11mm x 1.25. They are 38mm long. Each has two flat washers and a nut.
 
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I think I just stumbled upon the 4 rear 11mm wheelwell bolts. 28mm long w/heavy lock washers. Japanese?
20E34727-0ACA-4AA1-B210-C70FDAEEEF5D.webp


One still has a red fibre washer.
9D0593B9-07F6-43AA-A786-3E80589DB7D9.webp
 
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