I have -05 S60 with 2.4l gasoline engine and it has developed stiff streering over let's say maybe 4-5 months.
When going straight and start turning the streering is stiff and when keep turning it gets 'normal' and then when streering wheel is about 180deg it gets stiff again and if I keep turning it gets 'normal' again until streering wheel gets to 360deg etc..

From the symptons I would assume it's the joint in the steering axle that is the cuprit. When I tested it with front wheels off the ground and engine not running (I didn't think of testing with engine running at the time. I'll have to re-test it with engine running so that power steering is working) I could feel the stiffening but very very faintly. Almost undetectable. Could it be the power steering rack? Anyone else have had similar issue?

Also when I tested the steering and it's getting stiff engine does not change it's tone like power steering is working harder like it does for example when you are turning againts steering stop so that's why I also assume that faul has to be before or at the power steering.

What I looked into it it the joint seem quite pain to change. I think I might need to remove the power steering rack to get to the joint?

 

Okay so I did some testing. I went and lifted front wheels off the ground and without starting the engine turn wheels left and right and the stiff spots were still there so I guess I can rule out the power steering in this case.

Then I started the engine and stiff sports were still same so they didn't change at first, but when I kept turning wheels left and right sometimes the steering went back to normal without any stiff spots and after couple left/right they came back.

So it seems that the joint is bad and I think it's the one outside not inside the cabin because it's out in the elements. Question is that can it be changed without lowering the subframe etc.? I tried to look into it but couldn't find anything definitive. From one instruction I got impression you could access it somehow from cabin as well, but folding the floormatt and removing some cover?

 

Did more googling and it seems that the problem is most likely that join I was talking and it seems you can try lubricate it as first aid 'fix'. So I'll try that. Thanks.