Optimal Fluid for my Power Steering Rack

Apr 5, 2018
Mercedes W163 ML 320 2002. 250K KM on it.
Power steering Rack was leaking since i bought the car.
Very common issue with this model.
A year ago I found the most well known P/S mechanic in the country, a friend of my cousin. He inspected and said, in my case it is leaking from steering shaft side.
He told, if it is leaking from this site, Replacing steering shaft seal does not help, because there usually is circular worn at the metal wall at that site.

New rack is not available in the country, Since this is 20 Years old car, and rack is well known for such worn, it is not recommended to buy used one.
A Few months ago, That mechanic called me and told that he has new tool for sleeving that cylinder. I didn't want to be his first customer for such sleeving, i wanted him to get some experience on other customers. ( i admit, it sounds selfish :) )
2 weeks ago i visited him for repair. He finished the sleeving, But i am not sure if the sleeve was high quality metal or not because i imported those sleeves from China. Today i revisited him for inspection, it is 15 days that there is no leak yet.

I know, when optimal fluid specs are decided on, the balance between cold performance, protective ability for pump and gears all separately calculated. So oil can be optimised for one at the cost of sacrificing others
My country has warm climate, winter temps does not goes below +5 Degree most of the time. Oil pumps for my P/S are highly available in the country, and i do not mind harming it a little by wrong fluid if such fluid can reduce wear in the rack. I do not care about the steering performance too.
In this case, can oil, thicker than manufacturer increase lifespan of the rack ?
Jul 12, 2012
Caldwell Idaho
I have used shaft [savers] over the years and they work . It may be your only option as oil choice will not make a difference with the problem you are having. I am guessing the repair would use a part similar to this saver
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