Very bad Front end shaking vibration between 60 and 80 on 2001 Nissan Pathfinder

It is rear wheel drive and I have replaced the front wheel inner and outer bearings, and the rack and pinion assembly also had the front end aligned and tires balanced twice. I still get a very bad shaking at the steering wheel mostly between 65 and 75. What else can it be?

1 answer 1 comment
check tires for out of round or balancing
Thanks, probably out of round since the tires have been balanced several times.