Vibration starts at 60-65
 

I replaced the tie rods, had an alignment, tires are both equal and almost new. When the motor gets to about 65mph there's a subtle vibration and remains close about the same frequency at higher speeds but with some improvement. I feel it in the seat and in the steering wheel. I know its going to be something that will cost plenty of time and money to track down, but if I were to troubleshoot this problem, what would be the least to most expensive parts to replace?

Have you had the tires balanced?

hmm, no they weren't. I just assumed that they would be with the alignment.

Rotate and balance would be the first thing I would have done and that is a bad assumption.

I once got a set of tires that were out of round.

They would balance but still vibrated at higher speeds.

Jack the car up just enough to barely lift one tire off the ground.

Then spin the tire and see if the distance from the tire to the ground changes during rotation.

take the car and have all 4 tires balanced and make them do it until there are no vibrations at all.

My W123 vibrated and high speeds and it took me 3 tries at tire kingdom before my ride was as smooth as glass.

The dumb people that work there could care less and just slap wieghts on the wheels without checking a few more times to make that they are in the correct position.

what does the average balance cost?