I need to flush my auto trans and not sure what oil to use :confused:

Standard fluid from Mitsu.

Lots of threads covering this already!

You should use the Mitsubishi SP3 oil as this is the best one - about $45 for 4 litres from Mitsu and you'll need 3 bottles of it to do a full flush. The link to the workshop manual is attached and has instuctions within.....think it's in the service section or gearbox. If you cannot get the Mitsu oil, use any oil that meets SP3 specs.
http://www.mediafire.com/?2x32c6vvrcs55vv

Please instead of starting a new thread on a topic covered almost as many times as what exhaust to fit do a search