Below pictures shows the idea of saving:

For example, we can put the new tires 12-16.5 into 18.4-34, 10-16.5 into 18.4-30.

(1 )Packing quantity 12-16.5 460PCS/40HQ  18.4-34 70PCS/40HQ

When putting them together, the packing quantity is 

    12-16.5  112PCS,  18.4-34  70PCS，total 182PCS/40HQ

(2) Packing quantity 10-16.5 500PCS/40HQ  18.4-30 73PCS/40HQ

When putting them together, the packing quantity is  

    10-16.5  128PCS，18.4-30  73PCS，total 201PCS/40HQ 

There would be more tires in one container if we do in this way, and we can save more freight and space for clients