

2017 Chevy Cruze — very dark transmission fluid at 112k miles
I have a 2017 Cruze 1.4 with a six-speed automatic and 112,000 miles. I drained about 4 liters, and the fluid was very dark.
I had already prepared a clean pan in case I decided to pour it back. I got worried, so I returned 3 liters of the old fluid and added 1 liter of fresh ACDelco DEXRON-VI.
My plan is to replace 1 liter every 400 miles. Does this make sense, or should I just replace all 4 liters that drain out?