here is my review of the hot racing hard anno diff case and hard anno idler gear.
I first got my truck out on friday and ran several packs through the truck, unfortunaly due to some shock issues from the TiNi shafts I had, the shock screw kept coming undone. On saturday, i ran some practice laps and during the first heat i noticed my truck would spin out out of nowhere. Upon checking the play in the front diff I noticed that it would lock up when spinning oe side of the diff and would spin fine on the other. Between the secnd and third qualifier, I discovered that I had to remove the gasket to get the gears to mesh tight enough.
Here is why.


as you can see, the black side has a ring worn into it. That is because the recess machined into it where the washer underneath the sungear is deeper than the thickness of the washer. The gear rides and wear until it seats flush against the washer underneath it, causing the gear mesh to loosen. The loosening of the gear mesh was causing binding. When the gears would bind up, in a turn my truck would simply spin out. I was able to overcome the problem by adding an extra washer underneath the sungear.


and once again, as you can see on the back side of the black piece, a groove where the bearing was rubbing. This was unnoticable to me while driving, and i dont now if this is a problem. The outside of the diff, the actual gear itself looked great.

Now on to the idler gear.


i had no problems with the idler, and upon inspection, it showed a little wear on the outside edge of the teeth, but only time will tell if the wear continues. BTW the annodized did not wear, the metal slightly deformed.