Socket size (12 pt) for front axle output hub bolts?

B

blur911sc

New member
Dec 26, 2020
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> Be aware of the bolt lengths. You want the bolt to go all the way through the flange for maximum thread contact.
>
> BUT if you have a One-Ton front end, the axle flange on one side is thinner than the other side (or maybe both flanges are thinner than OEM.. I
> don't recall). This allows the bolt to extend through and it will hit the final drive casing. So those with the One-Ton must ensure the bolt shank
> does not extend through beyond the flange and check for clearances. I believe this affects the drivers side.

Dang, I finally got my new OE style cv boot installed and I just realized my new flange bolts are too short, I bought 1" and they have to be 1-1/4",
maybe even 1-1/2" would do.
Hard to find now, NLA at Grainger and Fastenal, checking some other places.

Some debate about if a typical split-ring lockwasher does any locking due to the bolt hardness, how about using Nord-locks?

--
Burl Vibert
Kingston, Ontario
1976 GMC 26 foot, Sheridan reno, don't know original model but we call her Roxie
 
Loctite blue works well.

Sully
Bellevue wa.

> > Be aware of the bolt lengths. You want the bolt to go all the way
> through the flange for maximum thread contact.
> >
> > BUT if you have a One-Ton front end, the axle flange on one side is
> thinner than the other side (or maybe both flanges are thinner than OEM.. I
> > don't recall). This allows the bolt to extend through and it will hit
> the final drive casing. So those with the One-Ton must ensure the bolt
> shank
> > does not extend through beyond the flange and check for clearances. I
> believe this affects the drivers side.
>
> Dang, I finally got my new OE style cv boot installed and I just realized
> my new flange bolts are too short, I bought 1" and they have to be 1-1/4",
> maybe even 1-1/2" would do.
> Hard to find now, NLA at Grainger and Fastenal, checking some other
> places.
>
> Some debate about if a typical split-ring lockwasher does any locking due
> to the bolt hardness, how about using Nord-locks?
>
> --
> Burl Vibert
> Kingston, Ontario
> 1976 GMC 26 foot, Sheridan reno, don't know original model but we call her
> Roxie
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
>
 
I was going to use Loctite blue, was debating whether ditching or changing the lockwasher was a good idea as well.
--
Burl Vibert
Kingston, Ontario
1976 GMC 26 foot, Sheridan reno, don't know original model but we call her Roxie
 
McMaster Carr
Heavy duty split washer product #91104A031 100ea
Alloy Steel 12 point Flange Head Cap Screw Product #91271A644

https://www.mcmaster.com/

> I was going to use Loctite blue, was debating whether ditching or changing
> the lockwasher was a good idea as well.
> --
> Burl Vibert
> Kingston, Ontario
> 1976 GMC 26 foot, Sheridan reno, don't know original model but we call her
> Roxie
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
>

--
Bruce Hart
1976 Palm Beach
LaGrange, Wyoming
GMC=Genetically Modified Chevy
 
Like Fastenal, you have to be a business to order from McMaster Carr in Canada

> McMaster Carr
> Heavy duty split washer product #91104A031 100ea
> Alloy Steel 12 point Flange Head Cap Screw Product #91271A644
>
> https://www.mcmaster.com/
>
>

>
> > I was going to use Loctite blue, was debating whether ditching or changing
> > the lockwasher was a good idea as well.
> > --
> > Burl Vibert
> > Kingston, Ontario
> > 1976 GMC 26 foot, Sheridan reno, don't know original model but we call her
> > Roxie
> > _______________________________________________
> > GMCnet mailing list
> > Unsubscribe or Change List Options:
> >
>
>
> --
> Bruce Hart
> 1976 Palm Beach
> LaGrange, Wyoming
> GMC=Genetically Modified Chevy
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:

--
Burl Vibert
Kingston, Ontario
1976 GMC 26 foot, Sheridan reno, don't know original model but we call her Roxie
 
Not in the USA.
Jim Hupy who orders from them all the time.
Salem, Oregon

> Like Fastenal, you have to be a business to order from McMaster Carr in
> Canada
>

> > McMaster Carr
> > Heavy duty split washer product #91104A031 100ea
> > Alloy Steel 12 point Flange Head Cap Screw Product #91271A644
> >
> > https://www.mcmaster.com/
> >
> >

> >
> > > I was going to use Loctite blue, was debating whether ditching or
> changing
> > > the lockwasher was a good idea as well.
> > > --
> > > Burl Vibert
> > > Kingston, Ontario
> > > 1976 GMC 26 foot, Sheridan reno, don't know original model but we
> call her
> > > Roxie
> > > _______________________________________________
> > > GMCnet mailing list
> > > Unsubscribe or Change List Options:
> > >
> >
> >
> > --
> > Bruce Hart
> > 1976 Palm Beach
> > LaGrange, Wyoming
> > GMC=Genetically Modified Chevy
> > _______________________________________________
> > GMCnet mailing list
> > Unsubscribe or Change List Options:
>
>
> --
> Burl Vibert
> Kingston, Ontario
> 1976 GMC 26 foot, Sheridan reno, don't know original model but we call her
> Roxie
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
>
 
> Dang, I finally got my new OE style cv boot installed and I just realized my new flange bolts are too short, I bought 1" and they have to be
> 1-1/4", maybe even 1-1/2" would do.
> Hard to find now, NLA at Grainger and Fastenal, checking some other places.
> Some debate about if a typical split-ring lockwasher does any locking due to the bolt hardness, how about using Nord-locks?

Burl,

The double hex of the OE screws was 3/8 and those that I could get were 7/16. I carry a jar of spares, the 1/2 drive socket and a clicker wrench in
case I should have to deal with them on the road. (This has happened once in 16 years and 70+K miles.....

You could have some American friend (you only have a few thousand) order them from McMaster-Carr and ship them to you as "used antique automobile
parts" so the customs guys don't get a bite....

Those screws are actually a super high grade part (equates to a SAE grade 10 or 12) and they are so hard and tensioned so high that split lock washers
will not work, they might be past the load limit of Nord-locks. Those also require that they be able to get a bite on the fastener. I did buy
hardened washer to go under them because of the load.

Installed correctly at 65~70Lb-Ft they are so close to yield that the chance of them backing out is slim, and they are too hard to drill for safety
wire. I thought about get some mash-keepers laser or water cut, but that is so far down my list of things I need to do that I don't expect it to be
near the surface any time soon.

Matt

--
Matt & Mary Colie - Chaumière -'73 Glacier 23 - Members GMCMI, GMCGL, GMCES
Electronically Controlled Quiet Engine Cooling Fan with OE Rear Drum Brakes with Applied Control Arms
SE Michigan - Near DTW - Twixt A2 and Detroit
 
No you do not need a business address to get Mcmaster stuff in Canada.

You order what ever you want and send it to my address and name. I take the package and relabel it as a "antique auto part" less than $40 CDN and
forward it to you using USPS/Canada Post. There is a one day delay getting it here out of Chicago and a second day for me to take it to the post
office. There are no CDN customs charges or brokerage fees that way.

Ken B.
--
Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana
 
> No you do not need a business address to get Mcmaster stuff in Canada.
>
> You order what ever you want and send it to my address and name. I take the package and relabel it as a "antique auto part" less than $40 CDN and
> forward it to you using USPS/Canada Post. There is a one day delay getting it here out of Chicago and a second day for me to take it to the post
> office. There are no CDN customs charges or brokerage fees that way.
>
> Ken B.

Thanks guys. Looks like Brafasco, a local industrial supplier, can get them for me at a good price, should be here in a few days.
I might take you up on that re-shipping thing someday though, you never know, so thanks again.
--
Burl Vibert
Kingston, Ontario
1976 GMC 26 foot, Sheridan reno, don't know original model but we call her Roxie
 
Any time. Just send me note or PM. I have sent a lot of relay mail for people. The largest was a GMC steering column. On rare occasion if I am
headed to Canada, I drive it across the border and drop it in Canada Post.

Ken B.
--
Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana
 
Any time. Just send me note or PM. I have sent a lot of relay mail for people. The largest was a GMC steering column. On rare occasion if I am
headed to Canada, I drive it across the border and drop it in Canada Post.

Ken B.
--
Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana
 
We notice that the bolts on the driverside is the one that seem to loosen
up so we always use the Blue Loc tite.
That is the side that connects directly to the Spider gear that can vibrate
more.
We deal with Imperial Supply as they supply shops at best prices and have
the assortment.
Only bolts they can supply is one with the 3/8 socket head, no more 7/16

> Any time. Just send me note or PM. I have sent a lot of relay mail for
> people. The largest was a GMC steering column. On rare occasion if I am
> headed to Canada, I drive it across the border and drop it in Canada
> Post.
>
> Ken B.
> --
> Ken Burton - N9KB
> 76 Palm Beach
> Hebron, Indiana
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
>

--
Jim Kanomata ASE
Applied/GMC, Newark,CA
jimk
http://www.gmcrvparts.com
1-800-752-7502
 
Since there is lots of clearance in there, is there anything wrong with using a regular hex head cap screw?

https://www.amazon.com/Bolts-Screws-Plating-Thread-Diameter/dp/B07CQ8ZGFZ

3/8-24 x 1 1/4 Hex Head Bolts, Steel Grade 9 Hex Head Cap Screws, Steel, Eco Guard Plating, Part THD Fine Thread, Diameter: 3/8 inch, Length: 1 1/4
inches, Thread Length: 1 inches
Hex Cap Screw Grade 9
Steel Ecoguard 1000 Hour Salt Spray - Gray/Silver Finish
Coarse Thread – Made in U.S.A.
Manufactured from 8647 /8640 /8740 Medium Carbon Alloy Steel
Tensile Strength: 180,000 psi. min,

--
Burl Vibert
Kingston, Ontario
1976 GMC 26 foot, Sheridan reno, don't know original model but we call her Roxie
 
> Since there is lots of clearance in there, is there anything wrong with using a regular hex head cap screw?
>
>
> https://www.amazon.com/Bolts-Screws-Plating-Thread-Diameter/dp/B07CQ8ZGFZ
>
> 3/8-24 x 1 1/4 Hex Head Bolts, Steel Grade 9 Hex Head Cap Screws, Steel, Eco Guard Plating, Part THD Fine Thread, Diameter: 3/8 inch, Length: 1
> 1/4 inches, Thread Length: 1 inches
> Hex Cap Screw Grade 9
> Steel Ecoguard 1000 Hour Salt Spray - Gray/Silver Finish
> Coarse Thread – Made in U.S.A.
> Manufactured from 8647 /8640 /8740 Medium Carbon Alloy Steel
> Tensile Strength: 180,000 psi. min,

I just answered my own question, it would be dicey to find a socket thin enough to fit a hex-head cap screw.
--
Burl Vibert
Kingston, Ontario
1976 GMC 26 foot, Sheridan reno, don't know original model but we call her Roxie
 
> I just took a closer look and answered my own question, it would be dicey to find a socket thin enough to fit a hex-head cap screw.

Burl,

With a yield at 180KSI, those should work. I would worry about the plating.
You could find a 9/16 (what it should be)-1/2 drive socket that would clear everything there, but there is still the problem that with a 9/16 hex will
be very close to its working limit at the 70 recommended final torque for those fasteners. You will still need the hardened washer to accommodate
the load on the flange surface.

Matt

--
Matt & Mary Colie - Chaumière -'73 Glacier 23 - Members GMCMI, GMCGL, GMCES
Electronically Controlled Quiet Engine Cooling Fan with OE Rear Drum Brakes with Applied Control Arms
SE Michigan - Near DTW - Twixt A2 and Detroit
 
I went down to the 'bolt room' at Coker Equipment in Gainesville with a sample. The Bolt Lady wander down a row and pulled out a sample, 12 hardness,
40 cents per. I had kept the original think washers and they had them as well. Red loctite and two hex drivers - they were the same diameter head
and surface but were hex drive. The NO (Next Owner) hasn't had a problem with tjhem that I've heard of, after the many miles I put on the coach before
I sold it.
Why Coker has such a good inventory in North Georgia of fasteners, I dunno, but pretty much anything that holds two things together they have and the
Bolt Lady knows where on the roughly thousand feet of floor to ceiling bins it resides.

--johnny
--
Foolish Carriage, 76 26' Eleganza(?) with beaucoup mods and add - ons.
Braselton, Ga.
I forgive them all, save those who hurt the dogs. They must answer to me in hell
 
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