I would check the manual on the fluid type to be used and then you know for sure. My 2004 1500 takes the same type 4 transmission fluid as the transmission. And yes the correct fluid makes a difference. My mother n law burned her pump up by using power steering fluid in it. It didn’t burn it up overnight but constant use of the wrong fluid will burn up the pump.

 

Necrothreading aside, I still VERY much question this. Apparently there were a few years of newer....Grand Cherokees, maybe?....that were picky about p/s fluid, but in 2nd Gen Rams I need someone to explain to me EXACTLY what is different in the steering box or Sag pump that would REQUIRE ATF+4 and could even tell the difference from basic Dex/Merc

The Sag pump is, AFAIK, exactly like any other Sag pump which was used in countless Big 3 vehicles for decades.

Chrysler only recommended ATF+4 because it was "their" fluid and thus their dealers were likely to have it on hand. Similarly, GM would recommend Dexron and Ford would recommend Mercon.

But I contend most recirculating ball steering systems just needed *a* light hydraulic fluid and virtually any ATF fits the bill. The specific properties of the additives or formulations in ATF+4 to Mercon to MercV to DexIII to DexVI are just superfluous and the steering system doesn't know or care.

I'm not suggesting I'd ever consider substituting Dex/Merc for, say, Pentosin -- merely that these older domestic truck systems are all VERY similar and have very basic fluid requirements.

 

Some folks try to get to damn scientific on here when someone just ask a simple question. About power steering fluids. My 2004 Ram 1500 calls for ATF+4. That’s exactly what she’s gonna get. Now some can question all you want about does it really matter if you use power steering fluid or ATF or 10 different types of ATF. My owners manual says ATF+4. You guys can use Dollar General power steering fluid, motor oil, vegetable oil or water. I don’t care what you use and what the chemical analysis of different ones are. If your brake fluid says type 4 are you gonna use Type 3? Or just a cheap can that just says brake fluid? Different fluids have different additives for friction and heat just as motor oils. The Chrysler engineers have figured out what the pump needs. Would you put Mercon in your Dodge transmission? If it doesn’t matter in the PS pump, why would it matter in your transmission? Fill your transmission with power steering fluid if it don’t matter, if it works in PS pump should be wonderful in the transmission too.

 

Well, the question becomes, other manufacturers use the same pumps/steering boxes, yet specify different fluids....... Why??

 

That’s a question you need to ask them, not me. I know the vehicle I got, I know what the manual says to use. That’s what I use and have had no trouble in 19 years with the truck. Must be doing something right, 04 model that’s only had regular services done by me since new. 1 set of brake pads and 2 sets of spark plugs, about to install the 3rd set soon. I do oil and filter every 2500 miles and transmission fluid and filter at 30,000 also rear end gear oil. It has never broken down and not a single part has had to be replaced. Like I said, use whatever you want in your pump, that’s what I do with ATF+4.

 

Sorry, there are explainable mechanical reasons why auto trannies need certain fluids and why DOT3 and DOT4 are required in certain braking systems.

But these power steering systems are just a basic hydraulic system that need *a* light hydraulic fluid. But again, if anyone can point me to seal composition or bushing material or ANYTHING else that will only survive with +4 but languish away with, say, Dex/Merc, I'm all ears!!

Finally-- and most importantly-- no one is suggesting you should not use +4 in your p/s system. I simply believe there's nothing wrong with observing the world and asking questions like if X=Y (generic Sag pump in a Dodge gets ATF+4) and Y=Z (generic Sag pump in a GM gets Dex/Merc), then *why* does X not equal Z??

If one does not wish to ask questions based upon observations, that's ok and is always the easiest course anyhow. I'm sure ATF+4 is "safe and effective" after all.....

 

Again, you would have to seek out the engineers that designed the pump. That’s not me. If I walk into an auto supply store because I need fluid for my truck, I’m not going to buy brand X because it’s 12 cents cheaper. If I’m needing fluid and I’m looking at the shelf, I’m grabbing what my vehicle calls for. A friend of mine was using his pressure washer a few weeks ago, it got low of oil and needed some. All he had around was some semi synthetic 20w40 V Twin oil. He put it in and after about 3 or 4 minutes of running, it started smoking and was really over heated. Almost locked it up. Most would think that if it’s an air cooled engine it should be fine, it wasn’t. Had to drain it out and go buy some10w30 and got back to work. I’m not an engineer but it did show me that fluids aren’t fluids and oil isn’t oil. I’m using ATF+4, use brand X and have a good day.

 

Oh and I fill all 2nd Gen p/s systems with inexpensive, readily available Dex/Merc. Never a problem even after 13+ years in some of them.

 

That’s great and fantastic. But if you run a shop you wouldn’t be touching a vehicle of mine. I don’t know why I keep getting replies to this when I’ve already said I don’t care if you run water in yours. I just said what the owners manual and engineers have said to run in mine. A thousand people can tell me what they run in theirs and I care less. I know my mother in law burned her pump up using generic Dollar General brand power steering fluid in her 2005 Ram in about 4 years. Also where I get my fluid ATF+4 it’s just as available as Dexron/Mercon and any other con on the shelf. Mercon ATF Type F is always available cheap too, fill your trans with that if you change your transmission fluid.

 

I just happen to look in the factory owners manual and it states to use "mopar power steering fluid" There is a caution/warning statement in there also it says "Do not use automatic transmission fluid in the pump reservoir, Damage to your vehicle will result". This should end this pissing match on what to use. Atf doesn't have lubricity as regular motor oil or ps fluid does. You may have heard people put a quart of motor oil in the transmission for this same purpose. I had an issue with one of my cars way back when it had a bad leaking ps box. I used ps fluid most of the time but when i ran out a started using atf. After running the atf for a while the reservoir o ring started to leak. The atf swelled the o ring. I think there is enough info here why to use the correct fluid.