I took my BMW 325i to a local shop to have it checked out. The biggest issues that they found with it were fluid problems. They claimed that both the transmission fluid and the power steering fluid were burned and needed to not only be replaced but also needed to be cleaned with a service that they would provide for a few hundred dollars. If I didn't they warned it could damage the transmission. They weren't lying about the fluid, its old and its dark and it smells burned. My question is how bad is having burned fluid? I've done some research and I know that the actual fluid is damaging and it seems as though just replacing it doesn't quite get rid of the problem. Is there any way I can run some sort of detergent through the transmission to clean out all the burned particles or is the shops information legitimate and buying their cleaning service really the way to go?