Ok, so I am overdue (at 44k miles) for a tranny fluid change on my '04 sportback (A/T obviously), and this is definitely one time when I wish the tranny was manual. The service would be so much easier (they have a drain plug).

My service manual isn't available to me for a while, and I haven't looked at it for six months or so, so I forget the process. Is this something I should do myself , or should I just pay a lube shop to hook up the A/T fluid machine, then change the filter at home on my own? It's unclear what the correct filter is for the vehicle. On rockauto's site, it doesn't show anything for an A/T filter kit, and looking up the 4g69 on a newer eclipse or outlander, it shows either a Beck/Arnley 0440322 (in pan) filter, or a B/A 0448000 (spin-on) filter. Are either of these correct?

So what should I do? A local lube shop offered to do the fluid change for $60 if I bring the fluid, and my mechanic said just a fluid change would be about $100. How much do I need to bring if they need to run it through the machine? The guy at the lube shop thought about 10-12 quarts. I'm thinking about the fluid that mitsubishi recommends, unless there is something better.

Is a transmission shop my best bet? WTF? This is way too complicated.

 

Some info from the dealer. They only do a flush. Apparently the car does not have a transmission filter. There is a "screen" as they put it, which is cleaned out with a flush. It uses special SP-III fluid, so the flush is more expensive. The dealer quoted me at $140.

I might just have a lube shop do it. There might be one or two in my area that don't have complete idiots working there.

Could someone tell me how much fluid I should buy? I'm not sure what the capacity is until I can get a hold of the manual again, and when it's run through the machine, I'm sure you need a bit more than is called for (to flush out the old). I vaguely remember this from my teenage days working in a lube shop.

Also, I have a good feeling this fluid will work well for this.
...or this stuff

 

Since no one can offer any info, and I'm getting the notorious sticky cabin heater temp. control knob fixed today, I'm having the dealer do it. I'll tell everyone how it goes...

 

Well, the stealership flushed the tranny fluid. $160 with tax and everything. That annoys me, but at least it's done.