Inspection of a 904 torqueflite
I will reuse the old fluid. It had about 30 miles on it.
What you can do to get rid of contaminates in fluids like trans or oil, even coolant is Go to the local paint store and get the cup filters for free. They have stacks of them. I actually do a pretty nice paint job, but to look at my car you wouldn’t know it.
What I do is use 1,2 or even 3 of these paper cup filters. They strain very fine particles out of paint. So when you start stacking them, you can get the smallest dust out of used fluids. A trick I learned to help with that problem, that works very well.