Is DEXRON OK in power steering
 

Good morning guys. the oil was changed in my friends 560SEL at the mb independent's shop. He topped the power steering off with red fluid. The pum has also been whining ever since....a pretty loud whine. Was this the wrong fluid or just some coincidence. My owners manual says only mb fluid which is clear.Any inpt. Second time posting it by the way and I can't believe nobody has any input so heres a second chance to help a guy out. Thanks one and all
Brian

Only if it is the old kind without Mercon.
Reference:

http://www.peachparts.com/shopforum/tech-help/25721-power-steering-fluid.html?highlight=mercon

Could be damaging the pump, assuming the red stuff was for sure modern Dextron. Best of luck to your friend in resolving the issue, Andrew Seidel.

The ATF blends have changed in the last few years and now have additives that are not healthy for the seals in you power steering system. But, I wouldn't think it would cause the system to whine.

I have used Power Steering fluid that I buy in a one quart container at the auto supply. I've been doing this for 8 or 10 years with great success. It's a little expensive, but a pittance compared to what MB power steering components cost.

Good luck,

The owner's manual for my '80 SD says to use ATF. Of course things change. I would use what is recommended in the manual. Though sometimes I wonder if manufactures recommendations to use their brand fluids, is just them repackaging off the shelf products but at a premium.

My mechanic friend tells me ATF is good for all rubber seals. I have used it in pnuematic nailers and airless paint sprayers upon recomendations of local repair shops. Have not had a problem with it. I have also used it to revive vacuum diaphrams. Seems to work.

Yes, your owners manual says ATF. Your owners manual was also printed in 1980, before ATF fluid blends moved in the direction that they have moved. They had no way of telling what ATF would be in the future when they printed the manual.

Everyone,

I am telling you that modern ATF is great for your A/T but not your power steering. I have seen printed in several places in the last 6 or 8 years that ATF, particularly Mercon has evolved to a point that it is not good for the seals in your power steering. I have lost the seal in the power steering pump on my 240D by running this stuff.

Power Steering fluid only costs about $2.98 at Auto Zone. That is twice the price of ATF. But the power steering pumps for most MB's cost at least $300.

I have switched to the relatively expensive power steering fluid in all my vehicles and have had no leaks or problems since.

If you insist on using ATF anyway, do yourself a favor and seek out some Type A.

Good luck,

My father has been able to use ATF in the powersteering pump in his Rolls, but then again its a GM pump anyway, and It has never been a problem in a pinch when he had a leak and needed to put somethign in there. After he fixed it, regular power steering fluid was always the best.

Now a benz is different, and I would hope that the Mercedes tech was only using mercedes or mercedes approved products in the car.

Alon

Well guys the power steering pump let go on the interstate last night...bearings sound like hell.. Is the replacement difficult to do?
Does anyone know the proceedure and how the system needs to be bled.. Thanks guys...BTW will be checking fastlane for the pump..any suggestions?
Brian

ATF may in time damage pump or seal. I doubt given the time frame on your friends car from the time of addition of fluid till the time of failure had anything at all to to with it. Ask yourself why it was necessary to add fluid to the system in the first place, and I believe you will find the cause of failure. (Lack of fluid)!!!!!!. Whine is caused by air in system,such as when it is not full of fluid. Can also in my experience be sucked in around pump shaft seal.
Just something to ponder.
Simplest fix would be just replace complete pump. Pretty straight forward job. Make sure steering reservoir is full before turning over engine after replacement of pump. I usually pull and ground ignition wire and spin over the engine a few times with the starter,then refill reservoir before starting. System will self bleed if you turn the steering wheel lock to lock a few times. Be sure to check hoses connections, and steering box for leakage. Watch carefully for the first few dozen miles for leaks.
Hope this helps some.

A reminder to old members, and educational data for new members.

Good info - just what I need to know for my power steering research.

Dont get mixed up with ATF and power steering fluid. They are not the same. Mercedes Benz car then use only mb fluids.

It is true that ATF has changed since the time these older Mercedes were manufactured. It was once a fine substitute but not anymore. You're basically guaranteed future issues if you use it exclusively. I use only synthetic power steering fluid in all of my old Benzes. Pentosin and Febi/Bilstein both make good ones. They range in color from a clearish fluid, to light amber/yellow to a greenish color.

The seals, hoses and steering box will last a lot longer with this type of fluid over modern ATF.

there is a way to figure this out.

Look in the owner's manual to see what fluids are recommended. If they say ATF, see what ATF they mention, even for power steering.

Next, go to the manufacturer's website and look at the data sheet for the ORIGINAL product, which should still be there.

Match the viscosity, wear and seal compatibility numbers on the original stuff with your newer replacement in that brand.

If you are looking for Dexron III go get the non-synthetic (available with a little looking) and you will find what you need.

I have never had a power steering issue on any MB, but I do change the fluid and filter every 100,000 miles and flush out the system with more fluid and check the belts.

You will notice a real difference in how fast the steering responds. I have, both in a 123 and a 126.

This is easier said than done!

For our older cars that MB said should use ATF Type A Suffix A, it is hard to find an ATF of that type these days.

I contacted Prestone (most easily obtainable PS fluid here in Canada). They make a number of different types. Scroll down on this page to see the various types. I asked whether I should use the very last one (for Euro cars) or otherwise which one. They said to use their basic Power Steering Fluid if spec says Type A Suffix A. It contains the anti-wear additives that current ATFs do not. It is probably good for most cars (not just Mb) built pre 1985 or so.

Kent seems to agree! . Fluid he is using is sold by Febi.