Quote:
Originally Posted by g96818
There's no marking to determine the grade of the fastener.
I measured the front bolts at 63 ft-lbs.
Didn't feel like there was thread locker, but if so then it would already be dry by now and the torque values would be wrong since those would now be considered the breakaway torque.
According to this video, there's no thread locker on the bolts. skip to 2:50.
https://www.youtube.com/watch?v=artb4VxLaig
front caliper bolts are 63 ft-lbs
rear caliper bolts are 32 ft-lbs
These are definitely not class 8.8 or 9.8 since the head size doesn't match.
The head size for a Class 8.8 M10 is 16 mm and M12 is 18 mm. My caliper bolts are 14mm and 17 mm so these are based off the old standard.
Also the chart you linked to doesn't apply since that chart is for hex head bolts, where as the caliper bolts are hex flange bolts. Hex flange bolts are torqued higher.
https://www.swtc.edu/Ag_Power/diesel...e%20values.pdf
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I know there is no markings on the bolts for what grade they are. I don't think Nissan would use the lowest grade, or the high grade bolt for this application. So I picked one in the middle, which would be 8.8.
The torque reading you are getting fall in line. Remember that you are not dealing with everyday bolting. This is Nissan speced. So the head size may not be what you are expecting. Car companies do some strange stuff.
I've rebuilt 4 sets of calipers so far. Of that. 3 had some type of thread locker on the threads. Most likely a triple boiled linseed oil. When I worked for Elliott TurboMachinery. We used to use this stuff all the time. Great thread lube until it drys.
Since the chart I linked to doesn't work. What chart would you use? And what torque would you use?
I hate to tell you. Those calipers in the video. Already have been apart, and cleaned. Plus when he took them apart. Where's the brake fluid? They have new pistons and seals already in them. The threads on the bolts have been wired brushed. The guy just took one side apart as a show and tell. He already screwed up in that video. He didn't put any brake fluid on the o-ring that goes between the halves.