How many quarts of transmission oil does my 98 outback 2.5 litre manual transmission hold? I bought three quarts already and have just been waiting to have a night to let it drain all the way out, I will try to do that tomorow. The guy at NAPA told me that 3 quarts would be fine, but then a friend with an 2.2 litre legacy said his tranny held 3.5. I just want to have everything I need. I also have a friend who has the same year of outback and said that I can switch out my speed sensor so I will try that also. My biggest setback is that I can't do any work on my car in the apartment complex that we live in. Thanks for your help I will report back once I do these two things and see the results. If anyone could give me any helpful hints with either of these actions it would be greatly appreciated. Thanks for your help.