Pcf8574ap to to manage the 4 address pins of 4067 multiplexer?
Most 74**4067 chips will support the CMOS (3.3 V) logic levels of your Raspberry Pi, however depending on the exact part you are using the required supply voltage may differ.

According to this data sheet for the TI version of the parts, the 74HC4067 is intended for use with CMOS logic and will work with a supply voltage from 2 V to 6 V while the 74HCT4067 is meant to be compatible with TTL logic and requires a supply voltage from 4.5 V to 5.5 V. That said, both should be compatible with CMOS logic on the inputs.

It seems likely that your problem is not actually with the levels you are providing to the selection inputs. It might be a good idea to try playing with the chip without the Raspberry Pi (manually connecting the selection inputs to VCC or GND) and make sure that the rest of your circuit is working properly before trying it with the Pi.

If you do end up needing level translation for something, an IO expander is probably not the best way to accomplish that. There is a Stack Exchange question here which covers the topic of level shifting for the Raspberry Pi.