the tires themselves.
usually what causes this type of problem can be a or the engine mounts but because it is in a certain speed you should go check your tires for the appropiate balance
the sound from your tires bouncing of the fence.
It could be that the back tires brakes are rusted and need new replacements or just need oil.
they said mine did this because my tires were not stock and were bigger then recommended
Retreaded tires are refurbished tires. Instead of winding up in a landfill, they are recoated with rubber and resold. They are safe and cheaper than new tires.
it is when u turn the tires lift the hit the ground
you may have a low tire or your tires are to big
The "screeching" of tires.
Could be motor mounts, the tires out of alignment or out of balance, or the steering needs work.
Could be a minor out of balance condition with one of the tires, or a minor alignment issue that is unnoticeable at lower speeds. Also the tires may not be rated for the speeds you are attempting and are distorting. Another possibility is a harmonic imbalance, the tread of the tires may create a noise that causes a wobble in the steering, the sound is always there but raises to a harmful pitch at a certain speed.
Typically this means the tires are out of round. I had the same issue and thought is was wheel bearings and all other stuff. got new tires and it was fine.
The speed ratings describe the durability of the tire at high speed, higher rated tires are of more sound construction.