I run my RCs on a rough off-road track (backyard) with little pebbles, and rocks imbedded in the soil (as shown in picture below). A layer of the mixture is usually in the corners.
I never had issues with my 1/8 buggy getting something lodged in center diff gear, but the ET410 picked up a little something extra the other day.
That little pebble sure was reeking havoc with my ears. I couldn't pinpoint the grinding noise. At first, I thought the set screw on the pinion gear had come loose (like it did once before)...nope. I put the truggy down to do another lap and noise went away, until I smacked the rear end on a rut or something. Apparently that jarred something (pebble) the wrong way again.
This is the first time in two months that this has happened. If this was happening every time I threw the truggy into a corner, I probably would be disappointed to the max. It would be hard for me to let this platform go, and search for a 1/10 truggy with enclosed spur gear/slipper clutch setup.
Anyways, a big shout out to Tekno RC for using a 32 pitch center diff gear! I know, by the looks of things, I had some debris go into gears; got chewed up, and spat back out.