Is there any difference between OEM and non-OEM engine coolant?

I was going to pick up some Prestone Coolant at Advance Auto. Is this fine or do I really need to get the OEM stuff? https://shop.advanceautoparts.com/p...e-all-makes-all-models-concentrate-antifreeze-coolant-1-gallon-af2000/7020012-P

As long as the chemistry is the same it shouldn't make a difference.

Just to be safe, I used this . https://www.valvoline.com/our-products/heavy-duty/zerex-g-40

Non-OEM is ok, but it's really important to use the correct stuff. Make sure you get Si-OAT coolant, don't just grab a bottle of the auto parts store green antifreeze. I also used Zerex G-40. It is not easy to find, my local NAPA store had to order it for me. Way cheaper than the Porsche -branded stuff, though.

I use standard green Prestone from Walmart in my 2008 Cayman S without noticing any issues. Now, I don't need to search out special coolant anytime I perform maintenance or part replacements. However, you will need to thoroughly flush the original coolant first. I have read that mixing the coolants can cause a reaction making a gel type solution.

I went with Waterless Coolent from Evans. Prep Fluid and Coolant was around $400. My shop labor cost was about the same. I had the water pump replaced as well. Yep, that's a butt load of cash for radiator fluid however it's a permant solution and it also eliminates any possible corrosion. ?

That stuff is a BAD idea on many levels. It's basically straight glycol, which is bad for heat transfer in multiple ways. There's a reason carmakers use 50/50 water glycol. I would not put that Evans stuff in any car I care about.

"Bad Idea"? Hmmm, ok...so if this is just your "opinion" so be it. If you can back it up...please do! Porsche using 50/50 has no relavance...it's "good enough" and that business model is followed throughout their product line..,until you get into "rarefied air".

Well, I'm an engineer. And the guys who designed your car are engineers. They're not trying to save bucks in this case: they know what they're doing. Evans coolant is basically straight glycol. Their original product was just ethylene glycol from what I can tell (like undiluted coolant you'd buy at the auto parts store.) It tended to gel at low temperatures, apparently because nobody at Evans bothered to look up the freezing point of EG. They later switched to an ethylene glycol / propylene glycol mixture to avoid this issue when they revised their product. That should give you a hint of the level of product testing you're dealing with here. Straight glycol has lower heat capacity, poorer thermal conductivity, and higher viscosity than a 50/50 glycol/water mix. These are all really bad things for heat transfer: they reduces the cooling capacity of your cooling system and make the car run hotter. Evans claims this higher temperature doesn't matter since the coolant won't boil over. That's bunk. Higher head temperatures make the car more prone to pinging, which causes the ECU to retard timing to compensate, which reduces power (see below for some data from Redline.) Higher temps are also not particularly great for engine life. Pure water gives the best thermal performance in a cooling system but will freeze (and doesn't have any corrosion protection.) 50/50 water/glycol is used by car manufacturers not because it's cheap, but because it gives a good balance between freeze protection and heat removal performance. If you live somewhere it doesn't get crazy cold you want *more* water, not less, to improve cooling system performance: 60/40 water/glycol is a good mix in temperate climates. It's your car and your money if you want to use the Evans stuff. But it sure isn't smart IMO. Just use a proper coolant mixture and change your coolant regularly ( Porsche says "lifetime," I change it every 5 years as recommended for other organic acid coolants) and corrosion won't be an issue. I've owned multiple 25+ year old cars that ran nothing but regular coolant and have never had significant cooling system corrosion. The only time it's a problem is where folks either use straight water or don't change the coolant on schedule.

I'm no engineer but I can tell you that the lifetime coolant that Porsche uses is nothing like the major brands you buy in the stores. I replaced the coolant in my old 2000 BS in 2008 because I couldn't believe this lifetime garbage. I didn't use the stuff directly from Porsche because of the high cost but got it from the OEM mfg'er. Sorry but I don't remember the specifics of who it was or what it cost but I'm sure that you can probably hunt it down.

Porsche doesn’t make coolant. The Porsche stuff is an off-the-shelf OAT coolant: IIRC it’s documented as Glacelf Auto Supra from Total in one of the service manuals. When I replaced mine I just used Prestone . Same chemistry.

Here's what I've learned over the years. The Germans, they like certain stuff. They like this special purple or bluish coolant. Don't throw just any stuff in there. Throw in what it requires. Everyone that is mentioning chemistry is correct. Look through certain documents on various cars and engines over the years and you'll learn that different materials require different chemicals. Own an old Ford diesel? They suffer from cavitation in the coolant sleeves, so you have to put a special additive to keep that from happening. Throw in whatever you want and you'll soon have a blown engine. Had an old BMW engine with Nikasil lining? be sure to use the correct low sulfur fuel or face a blown motor. There are examples like this all over the place. For the minor additional legwork, it pays off to do it right. my 2 cents

Of course they don't make the coolant like probably 80% of the car. They spec to a mfg. It's made by the same company does their power steering fluid and brake fluid.

Dear Mr. Engine Coolant Engineer... There are many flaws in what you have posted. The first coolant formulation was 100% propylene glycol which has an exceptionally low freezing point. Evans was the first company to use PG as an engine coolant; all the non-toxic PG formulations are based off their technology. Liquid water is a better heat transfer medium than glycol, but as a vapor it conducts almost no heat at all. The vapor expansion of water is over 1,200 times in size. It's powerful enough to make a steam engine functional. When water (and 50/50 water/glycol antifreeze) boils inside the small passages in a cooling system, the vapor pushes liquid coolant out and leaves the metal effectively dry. The metal temperature at these locations spikes by hundreds of degrees and creates the hot spots that cause detonation. In extreme situations, the exhaust side of the head will get so much hotter than the intake side that the head will warp, ruining the head gasket surface. Evans Coolant remains liquid even under circumstances where water-based antifreeze has vaporized. A coolant temperature that is destructively hot with antifreeze is not a problem with waterless coolant simply because liquid is still flowing across the metal carrying heat away. The race teams they work with report real life feedback from the worst of conditions; they have seen engines run fine (and win) with a broken coolant pump (no circulation except for convection). Water has been used to cool engines since the first commercially successful internal combustion engine in 1860. That engine suffered from vapor and overheating just as engines do today. ...there is really no need to apologize or respond as you have already made your case. Should you find yourself overly compelled to defend your "Ambiguous" Engineering prowess, feel free to correspondend with me directly! ?

Dude. You asked for an engineering explanation and I gave you one. No need to take that tone or make personal attacks. I'd explain to you why a lot of the marketing materials on advantages that you're quoting are misleading, but doesn't seem to be much of a point. Suffice it to say that you're trying to solve problems that aren't significant in a properly designed cooling system, and you're introducing a whole bunch of other potential problems. It's not exactly rocket science to run a straight PG/EG mix. If it were a good idea you'd see car manufacturers doing it. In general I try to remind myself that I'm not more clever than the guys who designed my car.

My only thought is, 50% glycol is cheaper than 100% glycol. That is one reason mfgs use it.

Well, the issue is that it's not just the coolant cost. You'd need to redesign the cooling system for glycol: larger, beefier water pump to increase the flow and handle the higher viscosity, more radiator area, maybe larger cooling channels. That adds more weight and cost. Probably other things I'm not thinking of: like I said, the guys who do this stuff professionally aren't dummies. EG/PG is a perfectly serviceable cooling liquid, I'd assume, provided you design a system for it. The issue is whether it's a good idea to just drop it into a system designed for 50/50, and I would argue not. The other problem with dropping this stuff in your car is you have to get pretty much all the water out first (the final Evans mix needs to be <3% water.) If you've ever changed coolant on a 987 you know that's a lot easier said than done: I suspect at minimum you'd really need to pull the radiators to get all the old coolant out, and there are likely other places that trap coolant. Don't do that and you've just wasted like $400 in new coolant. My question with this sort of thing is always "what sort of problem are you actually trying to solve?" And on a properly designed modern car I can't see one. Heck, a lot of race tracks ban glycol coolant (it's slippery and a traction hazard if there's a leak) so the cars run straight water. During freakin' races. You think you're going to have a problem with not enough glycol in your mix on the street? Seriously? Anyway, to get back to OP's question I just used Prestone 50/50 when I replaced my coolant. If I can believe service manual at Alldata , the stock fill for the 987.2 was Total Glacelf Auto Supra: looking at the SDS this is an EG coolant with 2-EHA as the corrosion inhibitor. Prestone is the same chemistry and works fine in my experience. Coolant changes on these cars are pretty easy if (and it's a reasonably big "if") you have access to a vacuum fill tool, which fortunately I do.

So much for "this stuff is bad for your car" Mr. Non Specific Engineer... EVANS COOLING SYSTEMS, INC. ANNOUNCES NEW WARRANTY STATEMENT 10/14/2011 Sharon, CT—Evans Cooling Systems, the developer of the world's only waterless engine coolant, has released its new Limited Warranty Statement. Evans is confident in its products and stands behind every gallon of coolant it sells. Using Evans waterless coolants will not affect the manufacturer's warranty. The Warranty is as follows: Limited Warranty If you install Evans Waterless Coolants in accordance with the appropriate instructions, and engine damage occurs, which has been documented and verified by industry accepted analytical testing to be the fault of Evans products, Evans Cooling Systems will pay for the repairs as outlined in its Product Liability Policy. If engine damage occurs that should be covered by the manufacturer's warranty, and if your warranty coverage is denied on the basis of having used Evans Waterless Coolants, and the manufacturer is not found liable under the Magnuson Moss Warranty Act, Evans Cooling Systems will pay for the declined warranty repairs as outlined above. This demonstrates the confidence Evans has in its patented waterless engine coolants, and provides assurance to its customers that Evans stands behind its products. "We've been asked repeatedly if our coolant voids the manufacturer's warranty and we want to alleviate those concerns once and for all" said Ed Coyle, Chief Operations Officer. "It was time to answer this question publicly, and avoid the perceived barrier to achieving the benefits of our waterless coolant." The benefits of using Evans waterless coolants include increased fuel economy, corrosion elimination, lower pressure, and reduced toxicity. A lifetime coolant, Evans is a safer alternative for the environment. Evans Cooling Systems, Inc., headquartered in Sharon, CT, has focused on engine cooling and related areas for over 25 years. Evans is committed to maintaining a cleaner, safer environment, and continually seeks to improve product choices for all major heavy duty engine users. For more information on Evans Cooling Systems, Inc. and Waterless Engine Coolants please visit www.evanscooling.com , or call [phone removed].

As an attorney . . . I see A LOT of IF's in that "Limited Warranty" and jumping through those hoops would be a big impediment. First you have to pay some engineers to prove the engine damage "which has been documented and verified by industry accepted analytical testing to be the fault of Evans products." Plus I'm quite sure they have calculated the number of times a consumer is going to switch out their factory coolant, at their own cost, DURING the car manufacturer's warranty period, which is going to be a very low percentage. Then, of that small group, the number of consumers who have an engine failure who will actually bother to pursue a Magnuson Moss Warranty Act claim (which is not easy to win against a car manufacturer with a gaggle of smart lawyers) is near zero. In the end, Evans isn't really taking that big a gamble by offering this warranty. But it is clever marketing material. It's your car and you made your choice on using the Evans stuff. If you didn't want to hear contrary advise, maybe you shouldn't have asked for it and then followed up with the "Mr. Non Specific Engineer" name calling. My opinion - which is worth exactly what I'm selling it for - is that the Evans stuff would be suitable for an old car that otherwise tends to overheat (maybe because of the pressure blowing out hoses or seals or some other reason that suits their product). Otherwise, if your car is not having a problem with cooling, what's the point of making the switch? The Evans stuff admittedly causes the engine to run hotter than one using water as coolant, and it's not a performance enhancement. The Evans website says it "maximizes BHP" but I didn't see that claim explained on their website. But to each their own.

Engineers, Lawyers...you all seem to have a penchant for qualifying your opinions with some merit badges. I'm going to start using my Eagle Scout, at 15yrs old, "Degree"...this is probably not the Forum where a B.A.Economics would be appropriate.

I personally believe a degree in chemical engineering, when discussing chemical properties, is a legitimate talking point when questioned about pertinence to the discussion. At the same time, a legal degree is pertinent when discussing the legal difficulties of trying to actually make a claim against a company's product. Interestingly, I'm not a lawyer and yet I mentally questioned the hoops a person would need to jump through to have successful claim on this one. I suspect chances of that are very low. An economics degree may give you great insights into many questions, and could even help you here also. But rudely discounting well thought out and explained commentary from those who seem to be knowledgeable, possibly even experts, in that field is quite short-sighted. MOO (MyOpinionOnly)

No one claimed to be a CHEMICAL engineer. Any lawyer can make a case "for/against" dependant upon numerous biases.

Well, you don't seem to care about merit badges, but I do have a BS & MS in Chemical Engineering, yes. I don't claim to be an expert on how to design automotive cooling systems but I've worked on my own cars for twenty years, so between that and my degree I think I know some stuff, and I wouldn't use Evans in my car. But feel free to believe the marketing materials form the guys who are trying to sell you overpriced coolant.

I’m curious, what problem is the Evans product solving in our engines? Engine coolant is designed to remove heat (heat transfer), remain viscously stable in low temperatures, have a high boiling point, prevent corrosion and remain chemically stable (pH and corrosion resistance) for a long time in use. Do our engines have a real-life tendency to develop local hot spots that cause damage from coolant flashing? Combustion chamber hot spots are typically caused by unburned fuel deposits, metal cracking (e.g. valve seat) and autoignition damage. Coolant-related damage is typically leaky head gaskets and warped heads (and wet garage floors from poorly-designed water pump failures ;-). Are we having problems in our engines that an even higher boiling point coolant solves? Or is this a cure in search of a problem? The appropriate economic question seems to be OEM $40/gallon vs aftermarket $20/gallon, not $400 vs $40. FwIW I used OEM when replacing coolant at about 80k miles (now have 105k) ‘cause the really cool Porsche logo on the jug looks good on my shop shelf ;-)

"I wouldn't use Evans in my car."...good to know, I'm shocked! and i understand, its probably not not in your budget. "But feel free"...aw, thank you! "to believe the marketing materials form(sic) the guys who are trying to sell you overpriced coolant."...actually I saw "Waterless Coolant", was intreaged with never dealing with the condition of my coolant again and no issues with corrosion...two indisputable benifits worth $1k...to me...just like the Color Correction, Ceramic Coating and a tastefull Tinting from the best Detail operation in the Greater Seattle area was...$3,700.00!...now stop trying to be so pious and indignant, at least at the same time...it's very un-engineeringly! ?

As far as I can tell, nothing. Every industry attracts businesses attempting to sell a better mousetrap to people who won't be able to tell any different. And they make a good living at it, too. Nothing wrong with that of course. But if it makes them feel better, they can spend their money on whatever they like, really. It doesn't matter what kind of objective evidence (or lack there of) is available to suggest otherwise.

Mr Reptile I think that you need to relax. This was a civilized discussion until you kicked into gear. But what I really don't understand, and never really can get my head around, is why one would NOT want to use the "approved" coolant in an expensive car? It seems to me that the "saving", if that is the objective, would be in the lack of shop fees in doing it yourself. Why compromise anything using the wrong coolant? Maybe it is OK but why bother? It doesn't need changing very often anyway.

Such passion over mundane consumable products. Who knew? Please be nice to each other. No name calling. Take that somewhere else. Here's an article that says you want anything that is OAT http://pedrosgarage.com/Site_5/Coolant_Antifreeze.html For the chemists, here's a discussion on Evans https://mechanics.stackexchange.com/questions/39388/evans-waterless-coolant All kinds of chemistry stuff in there. And here is for everyone else like me. There is a reason Porsche recommends certain products. I always find it amusing that the generic "internet experts" like to think they know more about cars than the people who designed them, build then, and sell them, particularly the engine break-in people who just want to drive them like they stole them. In the case of coolant, it's not just coolant but part of an overall thermal management system. Granted, this is the 987, two generations old, and not the 981 where I think new thermal management was introduced but the principles probably apply. The cars are meant to work a certain way. Change that at your own risk. Arguments about warranty periods for 987 cars are probably moot being long out of warranty. Be nice with each other. Thank you. and buy whatever you want. Its your money. Know the risks and proceed with whatever. But be educated in your decision. Choose wisely.

Eh, I just added the dude to my ignore list. You can do that here: https://www.planet-9.com/profile.php?do=ignorelist That's a good question, and it really depends on the car and what in particular you're talking about. Car mfrs don't make their own fluids, and generally they don't require a specific brand: they set a spec, and theoretically any product that meets that spec is fine. Take oil. You don't need to buy "Porsche" brand oil (although probably you can?) Porsche's got the A40 spec, and there's a whole bunch of manufacturers who make products that meet that spec. So you can argue about "which one is best" but really any of those brands and weights are fine. On the coolant front it's a bit different as they sort of hide the stock coolant spec, but you can find it. There's only so many coolant chemistries out there and Porsche uses a pretty basic off-the-shelf OAT coolant, so really no risk of compatibility issues. Given that these cars aren't really known for cooling system failures (besides the water pump, which isn't coolant-chemistry related) I'm comfortable making the switch. Some specific car brands or engines have quirks where they're super sensitive to a specific product so you need to look out for that, but in this case that doesn't seem to be an issue. Yeah, it's only savings of $100 or so, but I avoid the feeling of being screwed, and it's nice to have the convenience of being able to just go up the street and get coolant rather than go all the way to the dealer or get it shipped. Like I said, I know stuff about this stuff so I'm comfortable in this case not using the factory fill in my car, but people need to make their own decisions: I wouldn't give someone crap for just using the Porsche stuff just to avoid complexity.

wow! forgot about this. i posted a simple statement about my coolant choice and all i get back is negative nonsense "warning" me what a bad idea this was. nope!...33k later i still never have to think about coolant. that was the goal, period.

Hopefully the trolls are gone (and I haven’t read the above posts). I bought Porsche coolant and if I couldn’t get it would have gone with an equivalent Euro coolant type. Shawn in VA (USA)