Drained coolant lower corner radiator. Opened reservoir cap. Noticed a second reservoir center engine front which looks to have separate radiator for turbo cooling. Do I drain this too or suck coolant out of reservoir and refill?

This might be similar: https://mbworld.org/forums/c63-c63s-...ml#post7823054

Thanks. I couldn’t find a response on a coolant change so I think I am going to suction out and refill.

You're welcome and sounds good, here is another thread on the two coolant thing: https://mbworld.org/forums/c450-c43-...x-coolant.html