when gradually speeding up to 40mph the front passenger tire jumps

You have an out of balance wheel and/or a loose part in the steering system or front suspension. Get it checked ASAP at a Ford specialist or alignment shop because it sounds like a safety issue. If you want to find a Ford specialist, here's our directory link for you: https://repairpal.com/ford-repair-in-manchester-new-hampshire

Your vehicle has a serious out of balance or broken /worn component problem. Have it checked soon it may be simple but not something you should put off. I would start with inspecting the tires for damage or if you have used a "fix-a-flat" type product that will also cause the problem you described.

Another cause could be bad or goin bad in the hub assembly wheel bearings