Steering shaft d40 Thai

[fuzzylogic]

Hi to all, my 2008 d40 King Cab Thai built, has developed an odd steering issue.
The ute now doesn't want to return to centre. Turn right, and she wants to continue to the right. same for left.
I took off the tie rod ends from the wheels, and both sides appear to move freely. I'm guessing it's the uni joints in the steering shaft?
Anyone had this issue? Also, I can only find replacements for Spain built...
Whether it's a co-incidence or not, it became noticeable after driving through a flooded street. I went pretty slow, water was about 300mm deep.
Ute has about 270K kms...

Cheers

 

[fuzzylogic]

I've found a replacement on Ebay, brand new, but looks a bit different to mine, or 2nd hand (looks identical). Reckon 2nd hand is a waste of time?

 

[Old.Tony]

This is an odd problem, the steering mechanicals of the car are set up in such a way that the contact point on the ground of the front wheels is ever so slightly behind the axis of steering rotation of the wheel, so like a caster on a shopping trolley, the wheel will always "want" to follow a straight path.

I wonder if the caster angle is wrong? It'd be worth taking it to a wheel alignment shop, they can measure this sort of thing. It's only supposed to be a couple of degrees, the human eye might not even pick it.

 

[fuzzylogic]

Feels like something is sticky, not allowing free movement of the steering mechanism, I'm guessing the steering shaft, or something wrong inside the rack. Good point about castor though Tony...

 

[Old.Tony]

You'd know if there was something wrong with the rack/shaft if you elevated both front wheels and tried the steering. Is there enough fluid in the power steering pump?