Vibration in accelerator-85 c10?

I drive in overdrive constantly but when i shifted the 700r4 into drive it seemed to vibrate around 30 45 and 65 and this happens until i release it a bit. Its been a while so i may be noticing it ow more so than earlier. I tend to floor it a lot to make it uphill in OD. Could it be the joints on my 1 piece solid cast drive-shaft? is my going. is it high rpms in the engine any ideas?