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Torque for 9/16 greaseable bolts?

dremu

dremu

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I did search here, and looked on ORD's webpage (wherein I bought the things, lo these many years ago) ... but dang if I can find anything. I'm sure there were instructions with them, but they are long since lost :doah:

Looks like a standard 9/16 coarse would take about 110 ft-lbs for grade 5, maybe 150 for grade 8.

Do the greaseables require any different torque than a regular bolt the same size?

-- A
 
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dremu said:
Do the greaseables require any different torque than a regular bolt the same size?

-- A
Click to expand...

i would imagine not..... drop Kert or Chris a pm... but i'm thinking the standard fastener torque chart will be the right number, greased or ungreased,..
 
You don't need near that much for a shackle bolt though if that's where you are using them.

Should be a torque spec, if memory serves its far less than the spec for the bolt based on size.

Just make sure you're using a nyloc or some other type of locking nut like a pinch lock or prevailing torque. Whatever the case may be.
 
cybrfire said:
You don't need near that much for a shackle bolt though if that's where you are using them.

Should be a torque spec, if memory serves its far less than the spec for the bolt based on size.

Just make sure you're using a nyloc or some other type of locking nut like a pinch lock or prevailing torque. Whatever the case may be.
Click to expand...

Ahh, that 'splains why I was seeing 40-50 ft-lbs for shackle bolts, which seemed way low. And yep, that's where they are.

Thanks Kert!

-- A
 
No prob bud. I was gona say 45 ft. lbs. but wasn't 100% and didn't want to guess.
 
Well I did some Googling and came up with tables like that -- but those are for standard bolts, not drilled through, so the question is whether the greaseables need less torque.

But as Kert points out, I'll tighten 'em like any other shackle bolt and watch them like I do the U-bolts, should be good.

-- A
 
76zimmer said:
Whoa, I had no idea that cad or zinc plating reduces the torque required by 25%???

Also I would think a hollow bolt would have a reduction in strength because of a reduction in overall cross section, comparitively to a solid bolt of the same grade no?
Click to expand...


Not necessarily. Actually a tubular structure can be better at resisting torsional forces. It gets a little bit merky when you start throwing in the fact that the hole only goes so deep and the cross hole to let the grease out the side.
 
Couple examples of a tubular structure absorbing torque, Gun drilled axle shafts. Or better yet, a drive shaft. Relatively thin wall but a larger diameter.

All of it is very material to the overall strength.
 
76zimmer said:
Also I would think a hollow bolt would have a reduction in strength because of a reduction in overall cross section, comparitively to a solid bolt of the same grade no?
Click to expand...

A very, very small amount (a couple percent) yes. As mentioned, about 50 lbs is fine.

We use 50 lbs. for the shackle location as well and that one is much more important because by stepping up to a 1/2" bolt with our HD shackles (stock is 7/16") the sleeve is thinner. We build ours out of 4130 chromoly for that reason, but it's still more important not to overtorque those bolts.
 
Aaron, shackle bolts should not be any tighter than 50 ft/lbs. If you start cranking them down you'll destroy the inner sleeve because it will crush.
 
i put mine to about 50 ft lbs with the hand torque scale as i dont have a torque wrench.but if you go any tighter the sleeve will not be able to move and might start destroying the bushing as it sits against the shackle as well,and not letting the springs cycle cleanly through their arc which would not allow the shackle to flex under articulation.
 
Yep, tubular structures are usually stronger for lots of things than solid. Thick wall tubing will usually resist bending better than a solid rod of the same diameter.

But, in this deck there is a joker. And that is the hole drilled out the side to let the grease out.
Its pretty small, but I would suspect it would tend to create a stress riser and make it more likely to sheer at that point.
 
chulisohombre said:
i put mine to about 50 ft lbs with the hand torque scale as i dont have a torque wrench.but if you go any tighter the sleeve will not be able to move and might start destroying the bushing as it sits against the shackle as well,and not letting the springs cycle cleanly through their arc which would not allow the shackle to flex under articulation.
Click to expand...

The bolt shouldn't rotate inside the sleeve, the bolt and sleeve should be tight together against the shackle and then the sleeve should rotate inside the bushing. That's how polyurethane bushings work, and that's one of the advantages of the greasable setup is to keep grease in that location.

Fordum said:
Yep, tubular structures are usually stronger for lots of things than solid. Thick wall tubing will usually resist bending better than a solid rod of the same diameter.

But, in this deck there is a joker. And that is the hole drilled out the side to let the grease out.
Its pretty small, but I would suspect it would tend to create a stress riser and make it more likely to sheer at that point.
Click to expand...

The sleeves aren't loaded in a way that they would shear, if they were to fail they would buckle. As with everything, that tiny hole does make a difference but it's only a couple percent. Quality material/larger bolts etc make a MUCH bigger difference.
 
38377k5 said:
The bolt shouldn't rotate inside the sleeve, the bolt and sleeve should be tight together against the shackle and then the sleeve should rotate inside the bushing. That's how polyurethane bushings work, and that's one of the advantages of the greasable setup is to keep grease in that location.
Click to expand...
I totally agree. I see it suggested all the time to leave the bolts loose so the "spring can flex", but all this does is make the front end of the truck loose and turns the shackle holes into ovals (welcome your new clunk).

I suspect that rifle drilling a bolt does almost nothing to the torque rating, clamp load or shear strength. The cross hole is probably significant, but only at torques far above this application. There should be no shear in that region of the bolt and no torsion except while tightening.
 
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