Lump on the tyre?

[Big Rob]

Steering box bolts?

[utevanwgn]

Hi .
When did the problem start. If it started after some work was done It could be that. A vibration at a given speed is usually a harmonic IE a lot of little things not quite right all coming together at the same time. The spring shock combo could be not optimum + tie rod and idler arm ware + slight wheel balance prob and wheel run out all coming together at the same time and same speed.
Also you mention already replacing the springs . check the ride height left and right , cause there is a guide plate up inside the spring tower and sometimes the new springs get caught on the wrong side of of causing all sorts of clearance and driving issues.

[Indy Orange]

Yeah I made sure the springs were located correctly when I fitted them (tail end of the spring located in that recess ) I used Pedders springs and GT Monroe shockies.I am going to check for cracks first and replace tie rod ends and drag link balljoints and then go from there,cant really see it being a crack, this car has lead a sheltered life ,its a v8 though so could the extra weight cause cracks in V8s more?

[utevanwgn]

Could also be a wheel bearing being loose

[HK1837]

Yeah I made sure the springs were located correctly when I fitted them (tail end of the spring located in that recess ) I used Pedders springs and GT Monroe shockies.I am going to check for cracks first and replace tie rod ends and drag link balljoints and then go from there,cant really see it being a crack, this car has lead a sheltered life ,its a v8 though so could the extra weight cause cracks in V8s more?

Yes, they cracked especially on V8.