When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
On newer (1988+) model trucks with automatic transmissions, I think many of them have a plastic fitting at the bottom of the bell housing. If you remove that, then you will see the torque converter. You will have to either turn the engine over (remove the coil wire first) to turn the converter, but eventually you should see a little plug that can be removed with a rachet and extension. Your other option is to turn the engine with a rachet on the bolt in the center of the harmonic balance.
After draining like the other guy said in the other post, you would probably want to refill the converter as much as you can before firing it up. You don't really want to run the converter dry while you wait for it to refill by pumping from the pan.
So, you would turn the converter from a 6 o'clock position that you used to drain, to a higher position where you can still reach the hole. Use a handpump and try to fill the converter with as much ATF as you can and then put the plug back in.
Be sure to have a lot of ATF, the converter takes almost as much as the pan. I would make a wild guess that you will need at least 10qts, and I am probably low. I think the manual will be pretty close.
Like the other guy said, if you are draining the converter because of some problems, you don't want to just refill it since either junk from the tranny or junk from the converter will just cause more problems.