- May 3, 2014
- 89
Of course you are supposed to torque your lug nuts....
For many years, I never did, until now. This time, I thought I would do it right. The result was a broken lug. The lug was nearly brand new since I recently replaced both front hubs. For that job, I did manage to torque the hub bolts and axle nuts without issue.
I figured out today the main cause for the broken lug was an out-of-spec torque wrench. I have two torque wrenches with different ranges, and the one that broke the lug was breaking away at a much higher torque than the other wrench. I ran a test, and the good wrench (at least I think is the case) was at 50 ft-lb to move a lug nut tightened to 35 ft-lb by the bad wrench. I then set the bad wrench to 45 ft-lb and rotated the lug nut without the bad wrench breaking away. This time, I did not push my luck and stopped turning the nut before the wrench clicked.
I normally only use my torque wrenches when fluid seals are involved and for some of the more critical higher torque joints, such at the axle nut. Lug nuts would have fit the bill except that I had tightened lug nuts without issue for years before I owned a torque wrench. The last set of rotors developed a slight pulsation during heavy braking in less than a year, which could be caused by uneven lug nut torque, so I decided I would use the torque wrench with the new rotors. Not only did it take much longer to install the wheels, the first lug on the second wheel snapped off.
My old process was to put a little bit of penetrating oil on the lugs and tighten them as much as I could with a four-way lug wrench. It has worked for many years without issue. I decided to go back to that for now.
I'm curious. Are there are a lot of people out there not torquing lug nuts without problems? For those of you that do torque them, how often do you get your torque wrenches calibrated, and are there any special tricks to avoid breaking lugs (or other bolts)? I noticed that the lug nut seemed to be turning more than it should have, so maybe there is a rule of thumb for how far you should turn the nut past snug-tight before you suspect a torque wrench issue? Glad this was a lug nut and not something threaded into the block.
For many years, I never did, until now. This time, I thought I would do it right. The result was a broken lug. The lug was nearly brand new since I recently replaced both front hubs. For that job, I did manage to torque the hub bolts and axle nuts without issue.
I figured out today the main cause for the broken lug was an out-of-spec torque wrench. I have two torque wrenches with different ranges, and the one that broke the lug was breaking away at a much higher torque than the other wrench. I ran a test, and the good wrench (at least I think is the case) was at 50 ft-lb to move a lug nut tightened to 35 ft-lb by the bad wrench. I then set the bad wrench to 45 ft-lb and rotated the lug nut without the bad wrench breaking away. This time, I did not push my luck and stopped turning the nut before the wrench clicked.
I normally only use my torque wrenches when fluid seals are involved and for some of the more critical higher torque joints, such at the axle nut. Lug nuts would have fit the bill except that I had tightened lug nuts without issue for years before I owned a torque wrench. The last set of rotors developed a slight pulsation during heavy braking in less than a year, which could be caused by uneven lug nut torque, so I decided I would use the torque wrench with the new rotors. Not only did it take much longer to install the wheels, the first lug on the second wheel snapped off.
My old process was to put a little bit of penetrating oil on the lugs and tighten them as much as I could with a four-way lug wrench. It has worked for many years without issue. I decided to go back to that for now.
I'm curious. Are there are a lot of people out there not torquing lug nuts without problems? For those of you that do torque them, how often do you get your torque wrenches calibrated, and are there any special tricks to avoid breaking lugs (or other bolts)? I noticed that the lug nut seemed to be turning more than it should have, so maybe there is a rule of thumb for how far you should turn the nut past snug-tight before you suspect a torque wrench issue? Glad this was a lug nut and not something threaded into the block.