Visual inspection of the flap track can detect the loss of coating. One way to measure the depth of wear is using the intact area of coating as a baseline. Additionally, the CMM limits for the worn surfaces can be used as a general guideline for in-service wear limits made while the track is on the airplane. However, wear beyond the CMM limits should be reported to the aircraft manufacturer but does not necessarily mean that the track needs be removed from the airplane. Further information can be found in SL 737-SL-57-081 and Fleet Team Digest 737NG-FTD-57-01005. NOTE: The subject flap tracks do not require greasing of the roller surfaces. See illustrations for location. The inboard flaptracks can be replaced without removing the inboard flaps, with 2 man. Install a sling on the flap to make it weightless, then replace the track and afterwards check the skew sensor- and flap torquetube adjustments acc amm.