You can get all the fluid out yourself in the driveway, and change the filter. Use the transmission to pump the fluid out. You can also use the transmission to pump fluid in if you're afraid of it running dry for a few seconds. This all happens very fast if you start the engine. I always suggest that the person doing this use the emergency start mode, or disconnect the coil and fuel cut-off switch before using the starter to crank the engine. You'll need a couple of 5 gallon buckets. Disconnect the upper transmission cooler line. Use an old water hose or something to go over the top of that line and direct fluid to a bucket. This is very important since the flow rate of these transmissions is like 5 gpm at idle, and there's only a couple of gallons in there. You don't want T-fluid to get all over the place. My one and only engine fire was caused by T-fluid on exhaust.
Crank the engine for 15 secs or so, check the bucket, and keep up that ritual until the fluid is all drained out. That's a less abusive method. If want all the fluid out in like 5 seconds, just start the engine. Once all the fluid is out, you can much more easily remove the filter. Of course, expect some residual to be on the pan, but you shouldn't have to drain the pan from a corner for more than a minute. This method also removes the fluid from the TC.
Personally, I prefer the BMW method- just change the filter and whatever fluid that requires. The only time I change all the fluid is when we have bad overheating that I think has possibly damaged the transmission fluid, or the T-fluid has the fish smell. I might consider it if it was really black and burnt. Typically just a filter fixes those problems. Hopefully that will fix the problem with your GF's mother's car- IF she lets you work on it.
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Originally Posted by the user formerly known as ZX3_Chick
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