mcipseric

Hi,

What is the recommended steering rack / fluid maintenance and how do you do it?
My thoughts are that we talk a lot about changing the brake fluid, how about power steering fluid?

Thanks!

BobbyT

There are two ways to do this. One is to disconnect the lines from the steering rack and drain the fluid, but I haven't done this, so don't know any details.

I did mine by removing as much fluid from the power steering reservoir as possible with a bulb syringe, and refilling with the specified fluid. Then I drove the car for a few days to circulate the fluid, and repeated the process a couple more times. This may not remove the old fluid entirely, but I think it does an acceptable job.

randytrish

I did the same as Bobby did. I read a post here where someone disconnected the lines for the drain procedure at the rack and then developed a leak at the fitting.
Randy

Gunter

Owners Manual says 1 liter ATF.

But there are several types of ATF.
What type to use?

BobbyT

I used this, available from Pelican:

Pentosin CHF 202 is a synthetic high performance hydraulic fluid for life-time applications in modern vehicle aggregates. It is suitable for all extreme ambient temperatures and guarantees full performance from -40°C to 130°C system temperature.

This fluid supersedes the Pentosin CHF 11S, and is applicable to all Porsche 993, 996, 997, 980, 955 vehicles with convertible tops, power steering, self leveling suspensions, etc. Consult your owner's manual for details, capacities, etc. Appearance green/clear.

randytrish

I used Pentosin 202 power steering fluid.
Randy

dsmyth

I work with shops that replace all types of vital fluids on vehicles and the process that BobbyT described will remove over 95% of metal and rubber contaminents from the system. This has been documented with fluid testing before and after. You can feel the contaminents in the fluid with your fingers(use rubber gloves and rub it between your thumb and forefinger) before you can see them. The seal conditioners are used up before the lubricating properties in the fluids additive package. Proper replacement keeps the inside seals supple and minimizes copper,iron ,lead and tin particle damage. The pressure and heat is at times extreme in there and it is not filtered.

Mike J

I agree, Bobby T! (sorry, could not resist). I do it slightly differently, I disconnect the bottom of the reservoir and drain the entire container, fill, start the engine, steer the wheels left/right/left/right for a bit to circulate the fluid, then repeat.

Cheers,

Mike

Gunter

Mike,
What type fluid do you use and where can I buy it?

Weissach? Canadian Tire?

mcipseric

you guys are great! thank you!

Mike J

Hey Gunter!

Last time I used Pentosin CHF 11S (and still have a few cans for people who come in) and looks like I will need to upgrade when the next batch of jobs come through. I go through the stuff pretty slowly.

I bought the last batch in the US, cannot remember where (perhaps Pelican), but I noticed that Lordco has some on display when I last went into their store. You have a Lordco near you?

Cheers,

Mike

Ed Hughes

I'd think the sucking method is better than the "no method" Great thread!

I always wonder how many P-cars never even change their brake fluid!

dsmyth

Mikes point on moving the wheel back and forth is key as p/s fluid moves in small surges and does not circulate freely as you mignt expect. Thats why metal contaminants act like sandpaper going back and forth on internal parts.

Brake fluid absorbs 1% water per year ,and thats the good stuff. Two years and you have approx. 2% and pistons start to corrode. Also copper ions electroplate to abs valves. That you can't clean.

Gunter

Went to Lordco for the Pentosin power steering fluid:
$48.50 for one liter
Then I looked at the owner’s manual again and found that Tiptronic and power steering uses the same fluid:
ATF-Dexron II D.
Called Lordco and they carry the updated version:
Dexron III for $4.50 a liter
Dexron is Mineral, Pentosin is Synthetic.
Since Porsche used Dexron originally, I’ll go with it to avoid mixing Dino with Synthetic plus it’s a lot cheaper.
Any thoughts?

Mike J

I usually pick that stuff up in the US -- about $20/litre, so I have not considered a cheaper alternative...and its not something I replace that often. I think I last replaced it on my car about 3 years ago now..I figure on a car that costs this much, and the cost of problems, its cheap insurance.

Cheers,

Mike