Okay, to start off with it only vibrates under braking. However the rotors are good, they just got turned and are dead straight. You can hear it, and feel it through the steering wheel. Anything I should be looking at? I do have a set of Kosei K1 wheels with a wider offset, so do you think if my alignment is off on one side it could be causing this?

 

It's possible, are you sure the wheels are balanced properly also?

 

Wheels just got balanced. I am thinking my right front strut is bad, you think that would cause it? It gets worse as the miles grow so I think the fluid heats up in the cylinder and it loses damping and that causes the vibration. What do you think? Also what are good yet cheap replacements that will accept progress springs without problem? Will FE5 be the way to go?

 

Your rotors are fucked. Just because you had them turned doesn't fix a warpage issue completely, especially if they were really far gone to begin with.

Buy NEW rotors for the front. They're cheap, anyway.

 

But if I put my stock wheels on the vibration goes mostly away. My logic is that with the one strut leaking oil a bit under braking its compressing and rebounding on its own, losing the damping. The stock wheels sit further inboard so the effect is reduced, but with a wider offset when I got my time attack wheels on the effect is increased because the wheels sit further outboard of the strut. This is my logic as it is, what do you guys think? Also, would the SS struts be a better choice to match my progress springs? I have an LS and I think thats why they crapped out at 35k

 

I had a slight vibration in my TC with the stock tires but never thought anything of it. After putting my new tires on it got horribly worse, so bad in fact I started to question if my wheels were balanced. I remembered seeing a TSB for the TCs about those 08s in a certain VIN range the front rotors not meeting GM standards. In any case, I replaced mine with the R1s and the vibration is completely gone; looking at the rotor dead on I saw no warping at all but it was clearly out of balance enough to damned near right the wheel out of my hand.

In your case I would still be highly suspect of the rotor if it only happens under braking.

 

Exactly why I dont think its the rotor. It only happens during braking which leads me to a damper problem, since its under compression at that point.

 

It's your rotors. Turning the stock rotors is a waste of time and money. They will just warp faster after turning because they are thinner. If you can't get them replaced under warranty, it's time to upgrade.

 

That's exactly the same problem I had.