Front rotor fastener torque [message #307405] |
Mon, 19 September 2016 13:07 |
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wally
Messages: 643 Registered: August 2004 Location: Omaha Nebraska
Karma: 5
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I'm replacing a front rotor. The service manual page 5-42 shows fastener torque of 35 ft/lbs. They are 1/2 fine thread (20) and grade 8. They seemed way tighter than 35 ft/lbs when removing. Bolt torque charts read 65 to over 100 ft/lbs for this size fastener. Dumb question but is the manual right?
Wally Anderson
Omaha NE
75 Glenbrook
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Re: [GMCnet] Front rotor fastener torque [message #307411 is a reply to message #307410] |
Mon, 19 September 2016 14:24 |
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wally
Messages: 643 Registered: August 2004 Location: Omaha Nebraska
Karma: 5
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Senior Member |
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Matt Colie wrote on Mon, 19 September 2016 14:09James Hupy wrote on Mon, 19 September 2016 14:24It's not the bolts. It's the rotors. They are cast. 5 ea. 1/2" diameter grade 8 bolts @ 35 Pounds feet should hold em fine.
Jim Hupy
On Sep 19, 2016 11:13 AM, "Wally Anderson" wrote:
I'm replacing a front rotor. The service manual page 5-42 shows fastener torque of 35 ft/lbs. They are 1/2 fine thread (20) and grade 8. They seemed way tighter than 35 ft/lbs when removing. Bolt torque charts read 65 to over 100 ft/lbs for this size fastener. Dumb question but is the manual right?
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Wally Anderson
Wally,
The only reason for torque on a fastener like that is to be certain it is stretched enough to stay put. A lower grade fastener would have worked just fine as the suggested assembly load is no problem for anything above grade 3. They are probably Gr.8 because that is a low cost litigation stopper and that is all it is.
Matt
Thank you 35 ft/lbs it is.
Wally Anderson
Omaha NE
75 Glenbrook
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