Thanks for all of the input to help resolve my recently posted power steering issue. I'll be sure to let everyone know how long the fix lasts. I added fluid, which the dealer mentioned is fairly common (We'll see how common), and added some tire pressure. By the way, I have Michelin MXVs and every time the Volvo dealer balances and rotates my tires they set the cold inflation pressure at 25 psi. The recommended pressure on the fuel door of the car is 36 psi. The sidewall of the tire says 44 Max. I raised the pressure to about 30 psi just to see if it would further reduce the stress on the power steering and it made an even greater improvement than topping off the power steering fluid. In fact, the shudder is completely gone.

What tire pressure should be followed? It would seem there should be some agreement in all of these numbers. I assume wear would be a big component. They seem to be wearing quite nicely at the low pressures they have been running on since new. The first set I had were run at higher pressures and wore pretty quickly (Oh, and also thanks to the Volvo service department that obviously failed to rotate them during a scheduled maintenance).