Power Steering Fluid filter, which do I need?
 

http://www.autozone.com/N,14600949/shopping/partTypeResultSet.htm

I have an 85 300td.

I searched for power steering filters on a few auto supply store websites and have gotten a lot of different products.
In the above link, there are two products that came up. There is a cheap ($2.00) filter, and then the $20.00 filter. The $20.00 filter is what matches the item listed on the Parts section of this website.
I was curious if the other product is just a cartridge that I could use to replace the old cartridge, or do I need to buy the whole, more expensive assembly?
What makes me curious is that on two different company's websites, the $2.00 filter came up as the power steering filter for 85 300td.
What gives?

That is the correct filter. You might want to support this site and buy from Phil at the "Buy Parts" tab above rather than Autozone. But that is up to you.

$20 seems rather high for this - I just paid $15 at the MB dealer and that was in Canada, for one of these.

There's a power steering fluid filter?!

Yes, there is!

Can anyone think of what the $2.00 filter is? Just curious.

Some pictures here: http://www.dieselgiant.com/mercedespowersteeringfluidservice.htm

I can see I'm going to have to make myself a maintenance schedule with all to the required filters, fluids, belts, and hoses on it. How often does this power steering fluid filter need to be replaced? Roughly?

There is a "finger" type p/s filter sold for vehicles with 3/8" return lines. It's about three inches long, flexible and fits inside the return hose.

http://www.autozone.com/R,APP1031493/vehicleId,1653702/initialAction,partProductDetail/store,976/partType,00949/shopping/partProductDetail.htm

PS "Pump" filter
 

1.It Ain't $21.00.
2.It should say:Hengst,Mann or Wix.

Well it probably has not been replaced in most cars for the last 100K or so...;)

Power steering filter replacement schedule
 

Purists will probably kill me, but I think this is a once every 15 years/100K miles event, whichever comes first. In other words, if you have an old vehicle and have not done this, do it once and forget about it.

I used a cheap turkey basting syringe to empty most of the fluid out of the reservoir and then disconnected the return hose to pump the remaining old and dirty fluid out of the system - you need a helper to run the engine for a few seconds to do this, and an empty windshield washer bottle or similar to dump the fluid into.

The filter in my case had disintegrated into three separate pieces, which I fished out using some needle nose pliers.

Reconnect the hose, install new filter, fill it up with power steering fluid, engage engine, turn wheels from lock to lock, switch off, check fluid level and you are done.

Again purists may wish to use various high tech fluids but many owners now use regular power steering fluid.

Tip: avoid spilling fluid from hose onto clutch for AC compressor directly below. Gunks it up!

Tip no. 2 - I can't recall that this made any perceptible difference to the feel of the steering but I guess it helps to make the life of power steering system longer. Plus it's a nice easy job :)

hey dude since in old MB's like the W126 the power steering fuild is auto trans fuild i suggest, that you change it every 25K miles with a new filter Use a MANN filter the part number is H85. That way you will keep your steering pump free of crap, and new oil lubricates more and causes less heat damage i redo steering boxes at my shop so i know what happends in the inside!. I can tell you if you replace your power steering fuild and filter after 4 engine oil changes you will be allset for a long time! cya ;-)