N_Jay

On my 2000 A6 2.8 Quattro, I replaced the mineral steering fluid with CHF11s.
My understanding is the CHF111s is not directly compatible as a top up for mineral fluid, but as long as you change it all, you are good to go.
Since I had the system open, I drained it as completely as possible, turning the pump by hand and using a power bleeder on the reservoir to help push out any remaining fluid.
I then added a small amount of CHF11s and used the pump (by hand) to push it through the system as a flush.
I again drained the system well, and after reconnecting everything filled it with fresh CHF11s.
Turned the pump by hand to prime the system topping up as air was released into the reservoir.
After I was fairly sure I had it full enough, I started the car. Within seconds the reservoir was full of foaming fluid from remaining air.
Shut it down, let the bubbles settle, topped up the fluid and started it again.
I did this about 3 or 4 times till it had enough fluid in and air out to stop foaming and then one final time let it sit till the bubbles settled out and topped up.
The fluid is very clean and all seems to be working well, . . . . "except".
The steering "feels" rather light. Like it is a bit over-boosted for a European car.
I don't recall exactly what it was like before the accident, so I am not sure it is lighter then it should be, or just lighter than my other cars (MBs).

Thoughts?
Is there a known issue with running CHF11s in the 2000 power steering system?
Is there an adjustment for power steering boost level?

Prospeeder

CHF11S is what they come with from the factory. Interesting the steering feel changed. Iv always found A6's to be rather light on the steering.

jcman

From 1996 on Audi stopped using CHF 7.1 non-synthetic mineral base fluid in most all models to the synthetic Pentosin 11S mainly because the pump was not also assisting in braking in early 90's models, in fact you can mix both 7.1 and 11s in any C5.

N_Jay

The reservoir says "Mineral".

The feel might not have changed, I just did not remember it being so light.

jcman

I Know so does our 01 and 04 and to me it really means nothing, Audi should of been more informative and included "No Silicone Based Fluids" for the uninformed saving them from total disaster on the system.

Is it possible you replaced upper and lower CA's on this car recently?
It really makes a difference on steering resistance drag.

N_Jay

We did recently do 3 upper arms.

jcman

In March this year I replaced a power steering pump on the 01 my daughter drives and within weeks after that I replaced a TRE and both uppers on the pass side, she did mention that the steering felt more free and lighter then as I recall.