Small hi-jack.
What process causes this?
Taken from here as reference...
http://www.artcarr.com/page/news/1.acpp
Other External Problems
Aside from the items already mentioned, there is another external problem that should be addressed. Ground problems have been known to intensify thrust surface wear. Excessive current in the drivetrain can damage the thrust surface, which then affects the thrust bearing as though the thrust surface on the crank shaft isn't finished properly.
It's easy to check for excessive voltage in the drivetrain: Connect the negative lead of your DVOM to the negative post of the battery, and the positive lead to the transmission. You should see no more than 0.1 volts on your meter while the starter is cranking.
For an accurate test, the starter must operate for at least four seconds. It may be necessary to disable the ignition system so the engine won't start during the test.
If the voltage is excessive, check or replace the negative battery cable, or add ground straps from the engine to the frame, or the transmission to the frame.
Some systems may reach 0.3 volts momentarily without having a problem. For added assurance, improve the ground with a larger battery cable or additional ground straps.
Although the greatest current draw is usually while the starter is cranking, current in the drivetrain can occur while accessories are operating. That's why you should perform this voltage-drop test with the ignition on, and as many accessories operating as possible. Again, the threshold is 0.1 volt.
One final problem that may occur is current though the drivetrain, without measurable voltage. If the grounding problem is in the chassis but the engine and transmission ground is okay (or vice-versa), the vehicle may pass the test. What happens here is the ground circuit can be completed through the drive shaft and suspension.
To test this, measure the voltage drop with the drive shaft removed. Both the drivetrain and frame must pass the 0.1 volt test. This is where a ground strap from the engine or transmission to the frame does its best work.