I cannot work this out and would appreciate any help. It is a bit of a long story but please read it through.

(Ilive in Australia and the Hyundai models may be abit different.)
I have a Sonata 2 litre DOHC 16-valve. It was built on 1/6/98.
It has a steering pump on the LHS when you stand at the front facing the car.
A few months ago after servicing it I noticed th PS fluid was a tad low - no sign of a leak butI addedabout 1/2of a cup of Dexron 2.

About aweek ago I noticeda newnoise coming from the engine and when I opened the bonnet noticed a rumbling noise coming from thePS pump. It was not belt squeal. I thinkit's a bearing or the pump internals.

I don't know whether the fluid was the cause or it was a very odd coincidence.
Apparently PSF-3 is what Hyundai say must be used on my model, Dexron is okay for some others.

I have contacted 3 Hyundia dealers and they say different things. Twosaid they always use Dexron 3insteadPSF-3. Onedid not even have any PSF-3 in stock. PSF-3 is $27.40 per litre.
One said I must use PSF-3 but gave no reason.

The available lube information (Shell, Castrol, Mobil etc.)says on my model to use PSF-3 and NOT to use Dexron.
Nowhere can I find any specification for PSF-3 or anyexplanation why Dexron is unsuitable as a replacement.

There is a report of a similar event to mine on the internet. But there are also report from mechanics who say they alsways use Dexron and have never had any problem. One experienced mechanic said PSF-3 is just Dexron 2 and nothing special.

Q. What is PSF-3 and why must it be used? Did it stuff my PS pump?

A new pump is $700 here. But various parts for the pump are also available. I have yet to pull this one out.

sonnyboy

 

Just by your post I bet that PSF-3 fluid will be able to handle a higher pressure rack & pinion system. However, when it comes down to it if it was my vehicle - power steering fluid is still power steering fluid. Same goes for oil, everyone has their own brand but no auto manufacturer makes their own synthetic which is superior in lubricity to petroleum based oils! The only fluid I would be concerced about topping up is brake fluid, as there are several types and the majority of systems requires DOT-3 brake fluid as it is more reliable in the high heat that the brakes must endure. Anyway, if the vehicle isn't under warranty Hyundai can't say anything to you about what brand of fluid you use in YOUR vehicle. If your still in doubt just have it changed every 2-3 years.