The "coast" pattern is only half the battle. We need to check the "drive" side of the gear as well.

Again, the lighting makes it difficult to tell, but the pattern here is satisfactory as well. This gearset will not make any noise when running under load or under coasting conditions.

It is important to check the pattern in more than one spot. I usually choose 3 equally spaced parts of the ring gear. This will show any problems with runout.

Runout can also be checked on the back side of the gear with a dial indicator, but this is not always that accurate since the gear face can be flatter than indicated by any runout indicated on the back side.

Owner caption April 2018 · Photo 48 of 53