Rear engine mount bold substitute specs?

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Does anyone know the size bolts to substitute for the NLA 90102-13009 and 90102-13010? Those are the rear bolts that go through the hockey puck-style mounts. This would be simple if I had the correct bolts on there now, but my Central American truck not surpringly had random and incorrect looking hardware. I'm assuming it was supposed to be a 12mm bolt?
 

65swb45

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The 13 in the suffix code is the indicator that it is a 13mm bolt.

I have seen a lot of rigs over the years that replaced them with 1/2”x13 SAE hardware.
 

RAGINGMATT

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Does anyone know the size bolts to substitute for the NLA 90102-13009 and 90102-13010? Those are the rear bolts that go through the hockey puck-style mounts. This would be simple if I had the correct bolts on there now, but my Central American truck not surpringly had random and incorrect looking hardware. I'm assuming it was supposed to be a 12mm bolt?
.
 

Dizzy

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The OEM have a '5' on them, IIRC. I assume that they are soft steel, not high carbon for fatigue resistance. So I, so far, installed grade 5 SAE 1/2-20 (three lines on head) on my rig. I'd prefer the OEM, but mine look horrible.
 

RAGINGMATT

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@65swb45
@mrboatman
@Dizzy
@Pete483

No more SAE talk or @cruiseroutfit is going to be asked to move this thread to Chit-Chat ;)



- the 90102-13010 is a Class 5T bolt

- it is a 13mm x 1.5 thread pitch (edit )

- it measures 90mm long OD from under the hex cap or 100mm long OD from top of hex cap

- has a #5 engraved on 2 of the bolts and 1 has a Cast #5

- They are Post Paris Climate / Environmental treaty agreement Silver Zinc Plated

- the 5T 12mm x 1.5 thread pitch specified torque is 5.0 - 7.0 kg-m ( Kilogram meters )





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RAGINGMATT

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Matt, are you disagreeing that the suffix code indicates a 13mm bolt?

i just micrometer-ed it , & the OD results were 12mm , i measured at the threads , Not on the shaft

i see your point

Do we need a Edit here ?
 

RAGINGMATT

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I think so. My end is easy; you need to retake your pic on the shoulder of the bolt.

this might seem a bit Fred Flintstone approach

- the 12mm open end wrench fits snugly around the threads

- the 13mm open end wrench has Excessive Free-play

- was there ever a parts superscesion on this particular bolt # / part


o_O


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Dizzy

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Found on a February '75 USA 40.


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.504" at thread = 12.8mm, or 13mm (nominal), no significant difference at shoulder. Pitch matches nut that is still available new from SOR. One is long, 90mm; one is short 85mm.

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Dizzy

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I couldn't actually find a source for generic 13mm. The 1/2" is a closer diameter to a 13mm. Even the wrench to tighten them are, for practical purposes, interchangeable, 19mm, or 3/4". An SAE 13-pitch is close to a thread every 2mm. A 20-pitch is close to a 1.25 pitch. Course threads are inherently weaker, particularly in regard to fatigue (load and unloading cycles) because cracks propagate at the thread roots where there is less cross-sectional material to resist tension, and because the thread roots of course-threads are always smaller in diameter relative to a fine-thread of equivalent nominal size. SAE Grade 5 is akin to 8.8 metric, but there doesn't seem to be a much available that is lower than that. By no means am I suggesting that these SAE bolts are the most appropriate substitute for an OEM pair, nor am I suggesting that the specs on these SAE substitute bolts are not still in question.

For anyone reading this who has good OEM bolts, my guess is to keep them, and your frame, in good shape by replacing worn out rubber on all four corners so the bolts don't rub so much when the entire drivetrain is kinda loose on the frame. My driver-side mounting bolt, and its corresponding hole in the frame, is nearly a disaster.

I was planning on assembly, measuring the remaining thread past the nut, disassembly, then drilling the hole for a cotter pin on the bench with a second nut to hold the first one in place. The SOR 'hockey pucks' appear to have no metal on one side (OEM do?), so I'm thinking that I'd double the washers (Grade 5 SAE 7/16" fit best, IIRC) on that surface instead of making a bigger crater in the rubber. On the inside of the frame, on the driver's side, the original, or SOR washer, fits within the space provided. The torque required is relative to the bolt pitch, and hardness of the aftermarket 'hockey puck,' so I think that I will just 'wing-it' for assembly, and check for looseness periodically.
 
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I was going to comment on different lengths of bolts as I found out hard way when I reversed them when installing new mounts. One side would not tighten sufficiently and the other would not clear hole for cotter pin.
 
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