You can see the special pattern paint that gives me an idea of the Ring Gear to Pinion Gear Lash. I like to use this paint and I also look at the deposition of the the paint on non painted gears. These gears are hard and grow at temperature. The key is to know how much the gearset grows, the operating temperature at max load and the lash at that instant. I like lash at .002 to .004 at temp and load. You let the gear set cool and ultimately end up with .008 to .014 lash cold.
