I've used the Dayco XTX 5020 belt on my last two Pros and really like them.. They've lasted great and worked great ... Now Im looking for an after-market belt for my 17 assault and according to the Dayco fitment page it says to use the same 5020 belt... But from what I understand the axys takes a different belt then the pro?? Only one mention I can find in searching belts of anyone using the XTX 5020 so looking for a little input if anyone has ran the 5020 ..or another xtx number??... Thanks fellas