> At least at Discount Tire they use the color coded torque extensions on
> impact guns that will break if the manufactured-in torque is exceeded.
The torque sticks are actually little torsion bars. They work in
conjunction with the hammer in the impact wrench. The hammer will turn the
torque stick a little bit with each blow. This causes the torque stick to
twist. Between hammer blows the torque stick snaps back. A thin torque
stick takes less force to twist and therefore puts less torque on the lug
nut. A thick torque stick takes more force to twist and therefore puts more
torque on the lug nut. If you were to turn one of the torque sticks with a
breaker bar it would perform like a socket extention. When you use it with
an impact wrench it will torque the lugs the indicated amount every time.
It doesn't matter if you have 80 psi in the tank or 150 psi. It will
generate the desired torque.
I have heard that warpage in the brakes is actually thick and thin spots on
the disk that are caused by uneven wear and hot spots. When the pads don't
properly bed in the rotor surface can develop glazed over spots where the
pads don't grab as well. The glazed over spots don't wear as fast as the
rough areas. You end up with a thick spot. When you apply the brakes you
feel a pulsing in the pedal from the thick spot forcing the pads apart. You
can limit this from happening by doing a few things. First is that you
should get new rotors. The old ones have hot spots where the metal has
tempered unevenly. Second is to rebuild the calipers. A common mistake is
to not service the bushings on floating calipers while doing a brake job.
You can get a new kit or just clean up and lubricate the old parts so that
the floating calipers move freely. Third is to carefully bed in the brake
pads. You should make sure that the entire rotor surface gets a uniform
coating of the new pad material. This is accomplished by taking it easy for
the first several hundred miles. You should do several low medium and high
speed stops to get the pads broken in. Don't go out and do a bunch of panic
stops and overheat the brakes.
So often we do a brake job that is incomplete. The end result is warped
rotors. With attention to detail and patience during the bedding in time
you should decrease the chance of getting warped rotors.
Andy
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