2016 Mazda 3 coolant change - Are two D&Rs enough?

[xsr]

Hi all, I changed out the coolant on my 2016 Mazda 3 Skyactiv with about 130,000 km (~81k miles).
The car still had the original FL22 coolant so I decided to do two D&R cycles.
I used Zerex Asian Blue.


First D&R

• Drained about 3 liters from the radiator drain.
• Sucked out roughly 250ml from the reservoir.
• Refilled with Zerex Asian Blue.
• After several heat cycles and a long highway trip (about 175 miles), I checked the radiator and had to add about 200-250 ml more coolant after some air came out of the system.

Second D&R

• Did it after the coolant had time to mix.
• Drained about 2.8-2.9 liters from the radiator.
• Refilled with Zerex.
• Drove the car until operating temperature (~87-89°C coolant temp).
• Let it cool overnight

Next morning the radiator needed only about 60-70ml to top up.

Coolant temp is normal. No leaks.

Should I do one more D&R, or is two cycles enough at this point?

 

[dogememe]

I think you're OK but that' just my opinion. Mazda makes excellent vehices, Zerex is excellent coolant, and most people never change their coolant yet the cars last 300K.

 

[Lubener]

Two drain and fills is sufficient.

 

[Dave Hess]

Yes.

Simple and easy drain / refills.

 

[Kira]

Yup. Do the refresh BEFORE whatever fluid gets dirty.
People look so puzzled when I tell them this basic maintenance program.

NOTE:
The radiator in a 2010 Honda I maintained drained exactly 1 gallon of coolant when the drain rooster was opened.
Honda pre-mix came in gallons.
D'ya think that was by design?