My 2010 Subaru Forester was purchased used and I do not believe the transmission fluid was ever changed…should I do it now? It has almost 100,000 miles on it
That is a double edged sword. On one hand if it has never been done your fluid could be in bad shape. If yours has a filter that could need to be changed out as well. On the other hand fresh fluid could dislodge deposits that are not really causing any issues and move them into the passages of your valve body and block things up there or dislodge deposits that are blocking cracks in your gaskets and seals and cause leaks. If your sure it has never been done but the fluid is a good color I would say dont bother.
Change it along with the filter if applicable, if it kills it it was going to die anyway imhop.
You have two choices.
Do nothing, and let the transmission burn up.
Or, service the transmission fluid/filter, and know you did everything you could to prevent the transmission from burning up.
Change the fluid and a word of caution. Do NOT drain the transaxle final drive by mistake while changing the ATF and do NOT drain the final drive by mistake while changing the engine motor oil.
Believe it or not, many Subaru transaxles have been converted to scrap metal because of this kind of carelessness.