I am stumped

[smokediver]

I bought a new RTR JK and I was into my second pack and it started to make a clicking sound whenever it was in reverse. I have checked the mesh on spur and pinion. All seems good. It doesn't make the clicking sound going forward or reverse. All pretty much stock besides alum chubs knuckles and alum links. It sounds like when I use to get a small pebble stuck on my old RC10T2. But it looks clean with no dirt at all. Any ideas?

[BAWLER CRAWLER]

Idler gear in trans is my first thought.

[im gunna crawl]

Pull the transmission out with the leads still attached to the trans. Take the driveshafts off of the transmission. Run it to see if the noise is gone. There are 2 plastic transmission gears one of them may have chipped a gear. If that doesn't solve it. Put the driveshaft on the front only and run it. Then if its still there take the front driveshaft out and put the rear driveshaft in and run it. I'd hope that solves it. The noise could also be the pinion or spur gears, which are the big gears on the transmission, which could be under a cover if its the newer silver honcho or the new jeep body. Hope this is a helpful diagnostic check out of the basic scx10. Good luck.