Threadlocker for Disk Bolts

[trepetti]

I will be replacing the bolts that attach the front and rear disks to the wheels. The torque specs are relatively light (13 and 22 ft lbs respectively), and the service manual calls for thread-locker. I seem to recall having removed one of the bolts previously, and it was an SOB to loosen, leading me to believe that the PO had over-torqued them or they used the dreaded RED Loctite.

Looking at the specs, the Blue has a breakaway torque of 6 -12 ft lbs, while Red has 12 - 25. Since the service manual only specifies 'LT' where ever thread locker is needed (never a mention of Blue or Red), I am guessing (hoping!) that blue Blue is appropriate to keep these bolts from wiggling free.

Let me know if you have replaced your disks and which (if any) thread locker you used.

Thanks

 

[Gary in NJ]

Blue is the way to go. Heating a nut with thread lock is the sure way to loosen it, red or blue. Remember when you use a thread lock (or even never seize) that you have to use the wet torque value, not the dry one. The wet value is usually 10-15% higher. If a range is given, like 17-19 ft-lbs, I usually just use the higher value as the wet torque value.

 

[trepetti]

Thanks Gary. I am figuring that if the FSM specifies a torque of 22 ft lbs AND requires thread locker, the specified torque is the wet torque.

 

[MattR302]

Blue is the way to go. Heating a nut with thread lock is the sure way to loosen it, red or blue. Remember when you use a thread lock (or even never seize) that you have to use the wet torque value, not the dry one. The wet value is usually 10-15% higher. If a range is given, like 17-19 ft-lbs, I usually just use the higher value as the wet torque value.

Vice versa. The wet (lubricated) torque value is lower.

Torque = (clamping load)(bolt diameter)(friction coefficient)
Dry threads have a friction coeff about 0.2
Lubricated threads have a friction coeff about 0.15

So to keep the same clamping load, you would decrease the torque by about 25% if lubricating the threads.

 

[Gary in NJ]

I thinks this is where I say "opps". Wasn't thinking clearly on my day off.