New steering rack

[t44tq]

So I'm looking at Lucas Power Steering Racks from Australia:

https://www.steeringlpsr.com/product...-black-tag-lhd

It looks like this has been used by some members of the forum, with good results.

BTW, if a manufacturer says to use CHF 11S in the rack, why would you not follow their directions?

[jayjaya29]

Because the power steering pump was not designed to work with CHF. Also CHF is the devil if there are any leaks.

[t44tq]

Because the power steering pump was not designed to work with CHF. Also CHF is the devil if there are any leaks.

What is the issue with using CHF? Will it cause leaks? Is the viscosity or the chemical composition not right? To my understanding, the system was originally put in by the factory with ATF. But there is an updated reservoir bottle that has a "Use CHF 11S" label on it.

I'm just trying to learn why the change in fluid, what are the advantages/disadvantages, etc.

Thanks!

[bigjae46]

What is the issue with using CHF? Will it cause leaks? Is the viscosity or the chemical composition not right? To my understanding, the system was originally put in by the factory with ATF. But there is an updated reservoir bottle that has a "Use CHF 11S" label on it.

I'm just trying to learn why the change in fluid, what are the advantages/disadvantages, etc.

Thanks!

CHF is harder to find and for that reason alone I'd use ATF.

But there are PS caps with ATF, CFH11, and CHF11S...someone might have put the wrong cap on for some reason.

[jayjaya29]

ATF and CHF are not chemically compatible with each other. CHF is better for colder climates.

[Slideways]

CHF is harder to find and for that reason alone I'd use ATF.

But there are PS caps with ATF, CFH11, and CHF11S...someone might have put the wrong cap on for some reason.

If you buy a new ZF reservoir, it will have the CHF cap on it.

[t44tq]

If you buy a new ZF reservoir, it will have the CHF cap on it.

This is why I've been asking about why the change to CHF?

When I get the new rack, I'll make sure the shop knows to use ATF and replace the reservoir at the same time.

[jayjaya29]

Just a guess that CHF may be more stable long term. ATF has a tendency to become acidic over time and thus results in more leaks. Most people are not changing their power steering fluid as a part of regular maintenance.

[9kracing]

I have my old rack sitting in the garage, I'd sell for cheap if you want it.

My car has 50K miles.

I swapped it out for the blue tag, nothing wrong with it, it's pretty clean.

[prostcfc]

FWIW I was corresponding with Bimmerworld about their AAE units and they still use ATF in them for track applications even though it states to use CHF (disclaimer kept for warranty reasons perhaps, interpret that how you will).

For changing PS oil I generally just syphon out whatever is in the reservoir during an oil change and replace; easy enough to do and better than nothing.

[bigjae46]

Just a guess that CHF may be more stable long term. ATF has a tendency to become acidic over time and thus results in more leaks. Most people are not changing their power steering fluid as a part of regular maintenance.

I just vac out the reservoir and refill with every oil change. Seems to keep things working well.

[///m325i]

I have a brand new rack I believe from a z3. My friend gave it to me years ago and I forgot about it. Would these work in our cars?

[AWE46M3]

David has a freshly rebuilt one for sale. Bought mine from him and he went above and beyond rebuilding the rack and sent me pics and videos of every step of the process. Rack was packaged well and showed up quick via UPS. 10/10 recommend.

[liam821]

David has a freshly rebuilt one for sale. Bought mine from him and he went above and beyond rebuilding the rack and sent me pics and videos of every step of the process. Rack was packaged well and showed up quick via UPS. 10/10 recommend.

I was going to link this. David has been doing rebuilds for a while now.

[L0okitzRaj]

I also bought a rebuild from David. He is super thorough and did a great job with the rebuild! highly recommended