I have had this problem over the last few weeks....

What happens is i accelerate to anywhere between 35-50 mph. The truck starts to shake violently. It will continue to shake until i either accelerate or let off the gas.

i thought it was the new 20s and tires since i dont remember it before the wheels went on , but it does it at random speeds between 35-50 and instantly goes away by changing speed by 1-2mph. If it were the wheels it should do it every time at the same speed i believe. Its like the transmission isnt sure what its doing or something.

Does anyone else have this problem or have insight as to what it may be?

*its the 4.6l btw.

 

Get the wheels/tires road forced balanced. I bet that is your issue

 

^^^x2.

 

ok so my next question is i have driven about 1800 miles with it doing this mostly highway speeds at 65-75mph with no shaking. have a been wearing the tires badly?

 

I had tires that started to cause vibration at about 4,000 miles .After checking every other possibility I changed tires and no more problem. The maker and dealer lost a customer ! I went to another brand.
Most likely in my case and yours is that plys have separated .Have the tire man balance the tires .If the vibration continues change tires .

 

Sorry , DP

 

Well this is a shot in the dark but my 2009 did almost the same thing. i took it to the dealer and i would have bet alot of money the transmission was going, but they found a broken spark plug?? I've been around trucks for a long time and never would have thought this. Check it out it don't cost nothing.

 

take it to the dealer.