Any benefit swapping out primary for older style 2003-2005 Rev TRA...seems like the older primary's had limited issues with bushings some with 10,000 miles before they started to rattle but still functional....My 08 600 H.O. xp has 3,800 miles and some rattle on initial startup sounds like loose washers clears up after engagement......problably time for service or eplacement still holds rpms......Any comments welcome....Thankyou..... Gary