Surging in the steering wheel

[acools]

Gentlemen (and ladies),

Have a 2004 Volvo XC70, with almost 108K miles.

At highway (or divided carriageway speeds), when I am in a long sweeping turn, I get surging in the steering wheel.
The wheel surges a bit back and forth, but not enough yet to really affect the track through a curve.

Is this typically the pump or the rack?

Flushing the PS fluid is the best remediation? Then check for re-occurrence?

Best,

Andres

[guyeye]

I have a 2004 as well. I was experiencing the exact same thing, though somewhat irregularly. I read in another thread (or maybe it was another forum) that it was a sign of the inner seals in your rack starting to get weak, and let hydraulic fluid squeeze from one chamber to the other. I thoroughly flushed my steering system and it seems to have minimized the effect to the point that it only occurs when I'm standing still with the steering wheel "tensioned" (not maxed out to the stops, but turned so that it has a bit of tension on the wheel and the pump is working, and holding it there). I'm hoping the flushing "repaired" it to the point where it will last a while, but seals are always a weak link. I'm not kidding myself, these things don't "heal".

[passleft]

I also have a 2004 and was experiencing this. Mine seemed to mostly go away when I had the lower control arms were replaced. I know my power steering reservoir is leaking, and I had some power steering fluid added, so then again maybe that could have been part of the solution...

[Julien]

Hi Andres, I had exactly the same problem in my '04. After using a fluid treatment for 3000kms, the only remedy was a new rack. As it turns out, there was another '04 (a V70) in the shop the previous week with the same problem, could be a bad batch of racks with bad seals. Luckily mine was covered by extended warranty.
Good Luck.