bad vibration II

[speedyb-cc]

I took the car up to 45-50 in 2nd vibration there but minimal, at 70-75 very bad, put car in neutral at 75 vibration gone. When the vibration is bad you can feel it in the gas pedal and very strong from the shift lever. Local guy said it might be the pinion, possible?
Thanks ya'll (been in TX for 4 yrs and saying ya'll)
gotta love it
Bruce