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Power steering fluid

I had my 2001 Mazda Tribute (4 cylinder) serviced at one of those quick lube & oil change places 1000 miles ago, at which time they found my power steering fluid to be black and sludgy. They said that they had to flush it with new fluid 3 times to get it back to normal. I don’t think that had ever been done to the car at the dealership (I bought the car new and followed the recommended service to the letter). Now, 1000 miles later, I checked the fluid because I heard a very faint whirring or whizzing sound inside the car while sitting still and turning the wheel - it could just be my steering wheel - I don’t know - I cannot hear anything abnormal when I’m outside the car and someone else turns the wheel, but the fluid is black and sludgy again - and after only 1000 miles of very light use! What is going on? Is there a filter that needs to be changed or am I about to lose my power steering pump? Any insight anyone out there can provide will be greatly appreciated.

If they didn’t physically disconnect the lines to do a true fluid swap, they merely “turkey baster’d” the reservoir and cycled the fluid a bit. Probably left 50% or more of the old fluid.

Go to NAPA and get one of these

Part Number: 58964
UPC Number: 765809589643
Principal Application: Magnetic In-Line Transmission Filter 5/16" connections
All Applications
Style: In Line Transmission Filter
Service: Transmission
Height: 5.039
Outer Diameter Top: 2.402
Outer Diameter Bottom: Closed
By-Pass Valve Setting-PSI: 4.8
Burst Pressure-PSI: 200
Max Flow Rate: 2-3 GPM
Nominal Micron Rating: 25
Note: Universal In-Line Transmission Filter (Can also be used on Power Steering) Designed for todays Automatic Transmissions 5/16" Connection.

When you find a mechanic to install it (it’s a no brainer) have him/her also fully exchange the fluid. If you want to do a totally thorough job of it, consider Auto-Rx and add oz to the reservoir a few hundred miles before the fluid exchange. Your time line may make that a protracted thing, so you might consider a second flushing after the initial one (

The potential avoided costs are worth the $$ of correcting this.

Do NOT install that inline filter!! The PS system has way to high a flow rate for something that small.

If your fluid is turning black that fast, the rubber hoses are deteriorating and should be replaced. Also, INSIDE the fluid reservoir there is usually a filter SCREEN that may be plugged up with those hose particles, starving the pump for fluid and making the noise you hear…The reservoir should be removed and cleaned out and the hoses replaced…

I wouldn’t be surprised if they just changed part of the fluid (by draining the reservoir) then refilled it with some “universal” fluid that’s not the right stuff, causing the noise you now hear.

You should go to an independent non-chain mechanic and have the fluid fully exchanged with Mazda specified fluid.

Do NOT install that inline filter!! The PS system has way to high a flow rate for something that small.

Caddyman, you obviously have NO CONCEPT of how power steering works. The return to the (typically) plastic reservoir is LOW PRESSURE. REPEAT: LOW PRESSURE. They use the equivalent of trans cooler line (in many cases SAE J1019).

The high side (between the pump and the box/rack) is like 1200+lb …the low side is MAYBE …MAYBE 100 (usually much less).

It is you that is clueless…The return line may have low pressure but is has a high flow rate. Unless you are an automotive hydraulic engineer, I would not encourage people to modify their PS systems with a filter that could plug up or blow off resulting in power steering failure…

P/S flushes are part of recommended dealer services. I never recommend adding filters as they cause a restriction in the system that was not planned for by the manufacturer. The noise may be the normal noise of the system that you are just homing in on. I am assuming the system is full. It is very difficult to clean the P/S reservoir, so if you are judging the color by looking through a clear reservoir, that is not accurate. Take a drop of fluid on a piece of paper. it shoud be clear or have a tint of red, no particulates or cloudiness. If the fluid is dirty, and/or the pump is loud, have it checked by a mechanic. Chain stores and quick lubes do NOT have trained mechanics!

Again, Caddyshack, that filter has a bypass and is used widely on PS and transmission cooling lines. The engineers are at WIX and Raybestos. Complain to them about their lack of your unique insight into automotive power steering systems …and lay off the hard stuff.