I've heavily tested Gear Diff in 22 with many weights of oils and set-ups... on carpet or 100% grippy consistant surface dry astro they are awesome with much more forward drive, better braking improved steering (by killing off some of the aggressive 22 initial turn in)
On damp/wet tracks they are a handful, if a track has a slippy section of different astro etc then they can be very impredictable,these surfaces obviously require a much tamer acceleration and softer braking.
I've gone back to the ball diff, mainly because every meeting so far this season has been wet at some point!.. it's just predictable and more consistant ive found.
If you are running a standard layout XXX CR then you can fit the XXX-SCT complete gearbox (including all internals needed) which will give you a gear diff solution,you can't just buy the diff as it won't fit in gearbox case and needs different layshaft ratio gear from the truck too, idler is the same.
The 22 Diff won't fit a CR as its a different ratio and the diff gear/outdrives are a lot smaller and use metric bearings
Hope this helps
