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torque tube pinch bolt grade, strength

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Old 02-11-2019 | 03:41 PM
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vze2jshn
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Default torque tube pinch bolt grade, strength

WSM says torque to 35 ftlb for 8 grade bolt, 58 ftlb for 12.9 grade. I have 2 new black 93142124000 bolts how do I determine which grade and hence what torque? '78 US 5 speed.
Old 02-11-2019 | 04:32 PM
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Originally Posted by vze2jshn
WSM says torque to 35 ftlb for 8 grade bolt, 58 ftlb for 12.9 grade. I have 2 new black 93142124000 bolts how do I determine which grade and hence what torque? '78 US 5 speed.
The two pinch bolts in my automatic model GTS torque tube have that part number and they are torqued to 58 ft lbs or so I seem to remember.
Old 02-11-2019 | 04:48 PM
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Porsche issued a TSB to up the torque on the pinch bolts,
add 10% to the standard requirement of 58 ft/lbs.

So torque the driveshaft pinch bolts to 66 ft lbs add a drop of blue threadlocker to the threads.
the bolt may have 12.9 stamped into it this is the bolt strength grade, this is what it should be,
best bet post a picture of the bolts you have
Old 02-11-2019 | 05:02 PM
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Thanks gents. The 2 new bolts have no markings. Rear trans bolt (0ld) is marked 12.9 is also black and looks the same as fronts. Can I assume new torque specs mean fronts are -12.9? Old front bolts have no markings.
Old 02-11-2019 | 05:45 PM
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yes you could assume that if the bolts look like the each other



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