There is no good way to flush your transmission yourself IMO. There is an internal thermostat that closes at 165 *F and it does not allow you to flush the Torque Converter. So if the truck is driven to get the fluid hot, as the flush chemicals OR the new fluid is put in (cold) the thermostat will close and fluid will not be flushed from the Torque Converter.
If you want a flush, better to call around and find a shop with a heated flush machine. I have called about 10 different shops and have not found one w/ a heated machine yet. Some say they do, but I then ask them what machine they use and I look it up on the internet ............. still haven't found a dealership w/ one.
The manual states that you can drain the pan and refill every 30k miles.
If you choose to do this then:
drain the pan,
clean the internal screen (or replace it if it looks damaged),
put the pan back on,
refill w/ Mercon SP,
then change the external filter.
Last edited by bismic; 11-22-2009 at 04:15 PM.