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Coolant Type & Power Steering Type

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Hi all, another post asking for all the great wisdom this forum has to offer. I have a 2006 2500 5.9 auto and have some questions on routine maintenance.

1. Coolant is low and I have no idea what type of coolant was used previously. It is a new radiator as of two years ago and the coolant in the reservoir is orange. I have seen so many conflicting posts on coolant types and mixing types, etc. So, what type is needed and is it safe to add to system when type now is unknown? Engine temp is always around 188°F and truck has the Fleece Coolant Bypass System.

2. My power steering fluid is also low in the reservoir. Some searches brought up a multitude of thoughts on power steering fluid vs. ATF and honestly it was overwhelming trying to sort through all of the nonsense. What type of PS fluid can I top off the system with and is it better to do a flush of the system? I have no idea when the last time it was flushed. Steering feels fine and never makes noise.

Any good advice on how to flush power steering system if it is needed? Thanks for the help!
 
It's ATF, and the coolant is a HOAT from the factory.

Color of the coolant says absolutely nothing about its chemical propertys.
If you just want to top it of you need a "mixes with everything" type coolant.

The "low" PS fluid can be on purpose, I keep mine half an inch below the max mark to keep the reservoir from spilling ATF all over the place.
Flushing is easy, just take the hose of at the PS cooler below the radiator and let it drain.
 
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It's ATF, and the coolant is a HOAT from the factory.

Color of the coolant says absolutely nothing about its chemical propertys.
If you just want to top it of you need a "mixes with everything" type coolant.

The "low" PS fluid can be on purpose, I keep mine half an inch below the max mark to keep the reservoir from spilling ATF all over the place.
Flushing is easy, just take the hose of at the PS cooler below the radiator and let it drain.
Thanks Ozy. You're always a wealth of knowledge.
 
Your welcome.
If you travel like we do it's a life insurance to know the truck down to the bare bones.
So I do research and collect information all the time, every day - about almost any topic that crosses my way.
 
Your welcome.
If you travel like we do it's a life insurance to know the truck down to the bare bones.
So I do research and collect information all the time, every day - about almost any topic that crosses my way.
Trying to collect all information on this truck by any means necessary. Just makes it tough since its secondhand.

I was able to find the shop that replaced the radiator. I call them and they informed me that they use an "orange diesel coolant". They buy in bulk so he couldn't tell me if it was HOAT or OAT. The conversation was not very informative, but he said if I buy just an "orange diesel" coolant it should be fine to add. Does this make sense? He didn't seem to think it made a difference if it was HOAT or OAT. He did mention it was extended life coolant. Just don't want to do a system flush and also don't want to mix the wrong coolants together.
 
Yeah, the usual blablabla from their side.
So it's either a complete flush or you use a general spec coolant to top off.
 
Yeah, the usual blablabla from their side.
So it's either a complete flush or you use a general spec coolant to top off.
So any coolant that says "safe to mix with all coolant types and colors" should work? Apologies for the seemingly redundant questions, I just dug into the coolant debates today and I am down a big rabbit hole. I bought a jug of Peak All Vehicle and it says safe to use with all coolant types, but the idea of adding that to my truck weirds me out. The Fleetguard ES Compleat also states that its compatible with all other antifreeze/coolants, but again, not sure how truthful these statements are.

Again, you rock and I owe you a six pack or something.
 
Can the shop not tell you what brand/spec the orange diesel coolant is? Surely they have a record, or a label, since they probably buy it by the 55 gallon drum.

Since it’s very likely not the OEM HOAT fill any universal coolant should be good for topping off. It was generally the OEM HOAT that didn’t play nice with others, not the universal fluids mixed with it.

I used synthetic ATF in my 05’s PS reservoir. I never had an issue with it spilling, but the reports of spilling weren’t uncommon.
 
The universal ones can safely be mixed with any other coolant as their chemical composition is in a way that there is no reaction to other ones, like gelling which is feared the most.

Depending on location and amount of coolant missing you are also good to just top it off with water/distilled water. The small dilution is acceptable. It mixes itself from the reservoir as there is always coolant going for and back with every heat cycle.
 
Can the shop not tell you what brand/spec the orange diesel coolant is? Surely they have a record, or a label, since they probably buy it by the 55 gallon drum.

Since it’s very likely not the OEM HOAT fill any universal coolant should be good for topping off. It was generally the OEM HOAT that didn’t play nice with others, not the universal fluids mixed with it.

I used synthetic ATF in my 05’s PS reservoir. I never had an issue with it spilling, but the reports of spilling weren’t uncommon.
I am sure if he really wanted to he could have, but he didn't seem interested in helping. It's a "reputable" diesel shop in my town, as well. I am just going to top off the system with the Peak All Vehicle coolant and call it good until I can do a full flush.
 
If you went into a parts store they would tell you it requires the HOAT as mentioned but beware that if you buy concentrated HOAT you need to dilute it 50% with Distilled water. You can also buy it already diluted at 50/50. Tap water is not good to use. If it's low in two years you might have a poor seal on the reservoir cap. Not unusual to have some evaporation but mine usually go three years before dropping down the tank somewhat. Or it might not have been topped off two years ago when the change was made.
 
I do not put ATF in my power steering. I use to long ago when I was a kid. I use clear dedicated Power steering fluid. I researched it long ago, cant remember the details, but no ATF in steering
 
I have some on the shelf that is clear and specifically for Chrysler vehicles. Old ones in the 60's. Don't know why the difference but it might be in the seals they used back then.
 
I do not put ATF in my power steering. I use to long ago when I was a kid. I use clear dedicated Power steering fluid. I researched it long ago, cant remember the details, but no ATF in steering

You can put ATF in these trucks, that’s what they are built for.

I use PS fluid when it’s called for, but it’s not what these trucks call for.
 
There was a TSB that said to not use PS fluid in the new(er) Chrysler vehicles that call for ATF+4 which is indeed a fully synthetic hydraulic fluid with exceptionally good propertys all around.
 
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