I like to keep summer air in year round since summer air does not cause low air pressure like the cold winter air. In summer, I just top it off since there is no need to change it, and the valve acts as a filter, so it's good to go each time!

I do change the summer air when it's time to change tires.

__________________
RRGrassi


70's Southern Pacific #5608 Fairmont A-4 MOW car

13 VW JSW 2.0 TDI 193K, Tuned with DPF and EGR Delete.

91 W124 300D Turbo replaced, Pressure W/G actuator installed. 210K

90 Dodge D250 5.9 Cummins/5 speed. 400K