Builds Spyduh's Crawler80 Build

[spyduh]

one thing to note is that the clamping force is much tighter with the bigger hardware. I torqued down on it pretty hard. didn't use a TQ wrench and just snugged the crap out of them with a ratchet.

 

[Zjohnsonua]

Are you running 7/16-20 or 7/16-28 bolts?

 

[spyduh]

Are you running 7/16-20 or 7/16-28 bolts?

ARP bolts. Dunno the pitch but whatever that is

 

[Broski]

Are you running 7/16-20 or 7/16-28 bolts?

There 7/16- 20 bolts

 

[Zjohnsonua]

Gotcha. So clamp load is effectively the same assuming the same torque is applied, but shear strength is doubled. They're nothing to sneeze at, for sure.

 

[Broski]

FWIW, IMHO the clamp load is what holds it, when the hardware comes lose that when failures happens
For me if I was to go this route, I would use these bolts.

They are rear drive shaft bolts, I like the shoulder ( no threads to dig into the drive flange ) and something that's already on the truck, no need to add a SAE wrench's to the tool kit. If there strong enough for the drive shaft then they should hold up for the drive flange.

 

[baldilocks]

one thing to note is that the clamping force is much tighter with the bigger hardware. I torqued down on it pretty hard. didn't use a TQ wrench and just snugged the crap out of them with a ratchet.

A bolt is under twisting load as well as tensile load. Whereas, a stud is under only tensile load and also less apt to come loose. If you don’t torque those bolts to the max rating with a torque wrench, you’ve wasted your time.

 

[Ryan Towry]

per ARP's website, 7/16 bolts should be 70 Ft-lb max and 8mm should be 24 Ft-lbs max.

proper torque is important to prestretch the bolt sightly to ensure your flange and hub body dont seperate from each other and allow the bolt to go from a shear stress to a bending stress situation as the shear rating is alot higher than the bending/tensile rating.

 

[baldilocks]

per ARP's website, 7/16 bolts should be 70 Ft-lb max and 8mm should be 24 Ft-lbs max.

proper torque is important to prestretch the bolt sightly to ensure your flange and hub body dont seperate from each other and allow the bolt to go from a shear stress to a bending stress situation as the shear rating is alot higher than the bending/tensile rating.

Toyota spec is 26lbft on the hub studs. Front Range Off-road spec’s 30lbft for the ARP studs they sell.

 

[Ryan Towry]

Toyota spec is 26lbft on the hub studs. Front Range Off-road spec’s 30lbft for the ARP studs they sell.

yeah i was only looking at the generic bolt torque to show the drastic difference between 7/16 and 8mm.

 

[Broski]

I would be reluctant to tighten those bolts to 70 lbft
The ARP bolts are fine, but the new larger holes are now closer to the edge of the hub

 

[baldilocks]

I would be reluctant to tighten those bolts to 70 lbft
The ARP bolts are fine, but the new larger holes are now closer to the edge of the hub

I would do this mod if I had broken hub studs in the past but there is no consistent data telling me that I need to run larger hardware. I think that a 10mm stud would out perform a 7/16 bolt.

 

[spyduh]

5/16 x 1 hardened studs

 

[joez]

Do your wheels still clear the shoulder of the bolts? I know that has been an issue for others in the past.

 

[spyduh]

Do your wheels still clear the shoulder of the bolts? I know that has been an issue for others in the past.

Racelines clear with no mods

 

[cruisermatt]

I was tightening mine to 70 for a years now i just do 40ft lbs. i was starting to deform the Aisin hub bodies and axle flanges.

 

[Broski]

I was tightening mine to 70 for a years now i just do 40ft lbs. i was starting to deform the Aisin hub bodies and axle flanges.

This is what I was thinking 40 or 45 ft lbs

 

[spyduh]

This is what I was thinking 40 or 45 ft lbs

I did a pre torque to about 60lbs to get a pre-stretch

I loosened everything yesterday when I installed the pins and TQd it at 45lbs. prior to reading Cmatt's post.
I might loosen it again today and go down to 40lbs.

 

[cruisermatt]

I did a pre torque to about 60lbs to get a pre-stretch

I loosened everything yesterday when I installed the pins and TQd it at 45lbs. prior to reading Cmatt's post.
I might loosen it again today and go down to 40lbs.

You arent stretching these bolts with 60/70lbs. No way. Maybe 175ft lbs.

 

[scottryana]

Torque specs for ARP 7/16 bolt is 80-90ft/lbs.

Recommended Torque to Achieve Optimum Preload (Clamping Force) Using ARP Ultra-Torque® Fastener Assembly lubricant*​

ARPinstructions.com | Kit Instructions and Torque Values

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If you are only going to torque to 40-45ft/lbs a 7/16 bolt is kind of a waste in this application. IMO.

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