Question being how many runs before it is appropriate to have the transmission refreshed. Mine was built in 2012 with 150 runs of 1/8 mile over 3 seasons and no issues or metal flakes in the ATF change last fall. Just got to thinking how long is to long ? Mine has stock T350 gearing, all Coan innards & manual valve body, steel drum, 36 element sprague, 5-5-3- clutch pack. Footbrake racing, using 3500 - 3800 stall converter.