Based on the engine bay: being 4wd and recirculating ball steering: we are working with a gen3 donor, unless it had a gen4 swapped in

but yes you are correct: gen3 valley= 10mm gen4 valley= 13mm

both gen rear covers are 10mm heads tho

 

Yup, pretty common bolt overall; not "one of a kind" by any stretch of the imagination. Even looks like one of the head bolts actually.

Glad you got it identified. I hate it when I leave bolts out and have extra laying around, then later on something breaks or whatever because it turns out it wasn't bolted down... although we used to have a saying back in the 70s when I was a car radio tech (repairing them, not installing them) and they had about 7.3 million screws, and we'd joke that if you put one all back together and used all the screws you'd have to take it back apart again for something, but if you had a screw left over and didn't know how, it would be perfect. Wouldn't work if you deliberately left one out ; it had to be a mystery.

 

I don't think it's identified yet 😉

 

What year is the truck?
Looks like an Ac compressor line to Compressor bolt?

 

That bolt is 1.5" long not 2.5"

1.5 makes it approx 40 mm. So its a 8x1.25x40mm 13mm head


Look at that front bracket real closely and make sure you didn't miss putting a bolt in it.

 

Ah ******* hell

can't believe I missed that in the pic. I just went off the text

I'll see myself to the door now

 

Damn ya'll are good.

When I read the first post, I thought no way in hell. But ya'll proved me wrong

 

LOL it happens man.

We haven't solved it yet, that I'm aware of anyway.

 

did the same thing just parroted the length he said lol

 

Hello. Yes I have looked, with a mirror and poked around. I will look again, maybe it goes up from the bottom.
You are correct, it is not finished yet.

I have been busy, looking for where that bolt came from.
And getting the truck up and running. Changed the oil at 30 miles tonight.
All three bolts are in the power steering bracket. And they are not the same size as this extra bolt.
I started to look where that bolt came from before I put the block back in the chassis. I thought I would figure it out along the way.
I arranged the bolt bags--right and left. and if they where top side or bottom.
It was in the bag with the power steering bracket bolts.
A few grounds are 8mm1.25 but all the others that thread come in a group of the same length and this one does not match any of those groups.

Maybe a good dealership parts man could re-engineer by bolt size? I have no clue if that would work!
Thanks for all the comments, some day we will know the truth. And the extra bolt will find a home.