Humming noise on 2006 Toyota Tundra

After changing the air filter to a more expensive life time filter my truck started to make a humming noise when I would go 65mph and over. Could this be a serious problem beginning to start?

Asked by for the 2006 Toyota Tundra
first of all, get rid of the filter. put back the replacable unit. the k/n you purchased has oil in the element that contaminates the sensors.
the noise may be that the housing is not sealing correctly.