If I remember correctly, there is no loop on the 3000 pads, so your only method is to record realtime for as long as you need the pattern.
Or, split the pattern across several pads, pressing each in turn, with a big crash on the last one.
Or, don't use the pads, but program a composer ending. There is more editing available in the composer, the loop would be automatic, and even the crash could be added at the right place, or left out of the composer, and just the crash played on the pads.
I can't remember if this can be done on the 3000, but if you are in the composer see if a drum kit can be assigned to the accomp parts just like a normal sound. This would mean you can multitrack drum kits in the composer ending - the pads are only single track on the 3000. Might be easier to play that way.