JPTL

While following Socalgirl's thread re: her alternator problems and possible power steering leak, I learned something that I didn't know....our cars use ATF and not power steering fluid.
After doing my t-belt job, I lost most of the fluid as I needed to loosen the lower hose to get my fan shroud out.
Upon reinstall, I replaced the lost fluid with new power steering fluid, not ATF.
So what should I do? What's the diff. between ATF and PS fluid in our systems? Will a reservoir's worth of PS fluid harm the pump? Do I need to completely drain/flush the system, or can I drain out just what's in the reservoir and replace w/ATF?

dr bob

I'm not sure it will make a lot of difference. Most 'power steering fluids" are not quite as great as the best synthetic ATF's, but of course it all depends on the material inside and the particular fluid you chose. With good ATF as cheap as it is, you can do a little dilution of what you have with real ATF for just a few bucks in a few painless minutes.

Making the rash assumption that you replaced the reservoir when you did the PS fluid spill-and-fill in concert with your TB project, use a turkey baster to suction out the fluid in the reservoir. Fill with ATF. Run the car a bit including full lock-to-lock steering exercise. Turn the car off, and repeat until you've used up the three quarts of ATF you bought. Old stuff to oil recycle, where it shoiuld be worth well north of US$100/barrel in a month.

If my assumption about the new reservoir is poor, invest in a new one. Do the exercise described above, but put the return hose into a recovery bottle (looks a lot like an empty Mobil-1 5-qt jug or maybe a old empty bleach bottle) and cap or somehow seal the port on the reservoir. Have your trusty assistant start the engine and cycle the steering as you pour the three or four quarts of ATF into the reservoir. Stop the engine before the pump runs dry for more than a few secs. Replace the reservoir, reconnect the return line, pre-fill the reservoir with new ATF before starting the engine again. Folks reading along at home should consider this procedure every 25k, in parallel with changing the ATF in the trans. Just one big happy red puddle under the car.

A well-experienced mechanic once opined that most PS systems would last forever with a regular flush to get the old fluid and debris flushed out regularly. Any rocks or castoff bits from the pump or the other wearing parts will eventually find their way to the lowest spots in the system (the rack...) and hang there and cause wear until flushed out. It's cheap to test his theory.

JPTL

Thanks for that, Bob. I like the turkey baster idea. I might even buy one for the job instead of using the one in our kitchen (I probably want to avoid the comments about the Thanksgiving gravy tasting weird this Nov.)

Mrmerlin

if your by yourself jack up the car on stands and undo the 2 hoses connected to the bottom of the steering rack (they run down the fenderwell) let this drain turn the wheels lock to lock without the engine running, a few times till no more fluid comes out.
Install your new resivour and also replace both of the flex hoses, one can be cut off with a dremel (Its a short hose ) the other hose connects to the back of the pump and its easier to get to if the alternator is dropped down.
Re attach the lines to the rack use new copper sealing washers , add fluid to the resivour start the car and turn the wheels lock to lock( dont hold the wheel against the lock this is how the seals go bad in the rack, back off about 1 inch) about 5 times shut the car off and wait a few mins so the fluid will release the entrapped air. . Check the level and look for leaks

dr bob

Couple bucks each for a few at the local supermarket. One for oil, one for coolant, one for ATF, one for brake fluid. FWIW, ATF will cause you to have very regular guests at the dinner table. But it does let the turkey just glide over the tongue between dining shifts. Looks like good red table wine stains on the tablecloth, but they really do come out a LOT easier than real red wine stains. Really. Don't even try to think about how I know...

RyanPerrella

try a dollar store for a turkey baster

i would empty the reservoir and refill with some good ATF

I now use Mobil 1, previously used Redline

dr bob

The ZF power steering pumps are pretty gentle on the oil, plus we have that massive power steering fluid cooler loop in front of the condenser. Most 'power steering fluids' are likely compatible. I'd be most concerned that there might be some solvent or additive in power steering fluid that would accelerate deterioration of the hoses. I guess if I was swimming in full-synthetic Dexron I'd use that, but the duty for the PS is so light compared with what the ATF endures in the transmission, you can easily get by with a good standard Dexron ATF.

JPTL

+1 on the Dollar Store or Wally World. Emptying the reservoir a few times via your method is the way to go...plus it's so easy.
Funny, they've started to get on the ATF vs. PS fluid over on the "Alternator" thread.
MrMerlin, I understand replacing tired lines, but about replacing the reservoir....should these be replaced periodically? I lost my fluid not because of a leak @ the lines or reservoir, but because I'd loosened the hose clamp at the line & failed to tighten it up again while I did the t-belt job.
Are these reservoirs notorious for cracking, or what is it that makes them need to be replaced?

Jim bailey - 928 International

The "filter" is built in to the later plastic reservoir.

Jim bailey - 928 International

The reservoir is 928 347 015 05 about $25 .