I've always drained the torque converter. Even go as far as pulling off the lines to the trans cooler, but I'm no expert. Just never made sense to change 4 quarts and a filter to me. It'd be like dropping a quart of your engine oil, changing the filter, refilling and calling it good. But I'm no expert and may be throwing money away.

 

I haven't changed fluid in an automatic before, but i've heard you need drain the torque converter. How do you drain it? I know mechanics have some machine that cycles the old oil out while feeding in new oil so it all gets cleaned, but obviously I dont have one of those machines and i'd like to keep my costs down so i'd like to do it myself if i can.

Thanks.

 

Just did mine, took 7 qts Valvoline Synthetic ($6.50/qt.) on a pan drop/filter change. Not to bad of a job, the fluid was clean as a whistle coming out and very little sludge on the magnet (58,000 miles). Got a little worried that it wouldn't clear the exhaust, but it squeezed by.