PS fluid flush unsuccessful.
 

Power steering began to groan in the 126 car yesterday. The car still had ATF instead of PS fluid, and it was old and somehow there was air getting into the system.

I unhooked the return line after siphoning out the old fluid from the resevoir and ran 3 quarts of fresh PS fluid through the system.

I did not have a helper, so I could not turn the wheel back and forth, as only .5 quart could be run through the system at a time, before I had to kill engine and re-fill resevoir. With me?

So I hooked the R.line back up and filled system. Ran car and fluid is STILL RED.

Do I need to get a second person to get ALL of the old fluid out, or what?

Mike

My experience has been good using the method you describe. If you can't get a helper, then turn the wheel to one side, flush a reservoir full, then turn to the other. Even without turning the wheel three quarts should have flushed it. Are you sure that it is still red. Looking down into the reservoir the fluid will look dark anyway.

Good luck,

Well, the red is a mcuh lighter, and 'clear' red- but it is not clear as I had hoped the fluid would now be.

Is it ok to drive with some of the old ATF mixed in with the new PS fluid?

I will re-do the job this weekend with a helper.

Thanks.

I have asked many Benz mechanics and 3 different dealerships, and they all advise the use of Dexron Mercon 3 ATF in my 87 300E power steering pump.

What do you all think?

MBZ OE

In the above post I forgot to add that my car is not self leveling.

the way i flushed my ps fluid is by siphoning (using a fat syringe) out from the reservoir, then refilling it with ordinary ps fluid (from walmart). did it about 5 or 6 times, until fluid was close to crystal clear. filter was also replaced.

also tightened all connections which were sources of seepage and leakage - and groaning!!

I have run Dexron 3 for years with absolutely no problems. Dexron 3 is 100% compatible with the old "Type A"
specification, which MB used to recommend before switching to their own fluid (which, incidentally, seems to be a relabelled hydraulic oil manufactured by Elf).

If your system has ATF in it now, there's no reason to switch.

MB PS Fluid seems to be more like Type A ATF back when it was readily available. Its light weight presumably for better cold weather performance. Since MB also sells hydrualic oil, often for more money, I do not think the products are similar.

I know of people running Dexron III ATF and even one or two running Mobil 1 10w-30 motor oil in their systems.

However, many of us know that these systems MAY leak. It seems to me that some will and some won't. Use of one fluid or another is not a guarantee that the system will leak or it wont.

Since MB and the German companies in general have never specified American PS Fluid in their cars, choosing instead to use other specs, I have a hard time suggesting the use of American Power Steering Fluid. From talking with mechanics who have been fixing cars for 30 years, they tell me German rubber is "different" than American rubber, etc.

Regards,

>Since MB and the German companies in general have never specified American PS Fluid in their cars, choosing instead to use other specs, I have a hard time suggesting the use of American Power Steering Fluid. From talking with mechanics who have been fixing cars for 30 years, they tell me German rubber is "different" than American rubber, etc.


Brian,

So what would you recommend for fluid that will help prevent leaks for the german rubber seals?

I don't believe mixing both fluids for just a few days can cause any damage. Just don't quote me on that...
What you can freely quote me on - Is that I replaced the PS filter at the same time as changing over to MB PS fluid (honey color if I remember correctly). It has been about two years now and the system preforms as designed.Beautifully.
Furthermore, after reading about reconditioning old (german) seals , I added a few drops of brake fluid to the mix and a little while later , total happiness ..... - Away went the leak in the steering box!!