Alternatives to Dealer Fluids

Sorry to hear about the poor access. There is no filter for the transmission fluid.
You might be all right with DexCool (I haven't tried it).
Would you consider looking for someone who could ship the OEM fluids to you? I had good luck getting an online retailer to send me 1 gal. of OEM engine coolant for another non-Toyota car I own. It was not much more expensive (~50% extra) than aftermarket fluid, even with the shipping.

 

Unfortunately, there is a reason for the "use only Toyota fluids." The coolant in particular is a problem, since no one makes a chemically equivalent Super Long Life Coolant, and mixing different long life coolant types can cause corrosion problems. You're certainly better off not touching the inverter cooling system than using something other than Toyota Super Long Life Coolant. That is a sealed system and experiences much less heat wear/tear as compared to the engine. It should last the life of the car.

The engine, I would say just run with what you have in there until your water pump dies. My 2004 RAV4, filled with SLLC at the factory, made it 150,000 miles on the original coolant before the water pump finally gave out. Check your water pump any signs of a weep, and if it is ok, keep going.

On the trans, AMSOil makes a Low Viscosity Fuel Efficient fluid. It says Formulated for ... Toyota ATF WS on the label. But, it is more expensive than ATF WS, and I remember seeing some Prius-specific concerns posted elsewhere. Redline D6 claims the same and the cost is comparable to AMS, but Redline followers swear by it. Mobil 1 Synthetic makes no specific claim beyond T-IV compatibility but would probably work and is readily available. Key word on all of these being "probably." The hybrid trans being unique, I don't think you could ever get a straight answer from anyone regarding fluid substitution, though it is well known that Gen I filled with T-IV has a significantly higher trans failure rate than Gen II filled with WS, so don't use T-IV.

 

I've posted this before, I use Prestone extended life it is non-silicate, non-amine, non-nitrite, non-borate and is yellow, not green. I don't know what HOA (sounds like Toyota marketing) is, and but I can't see any technical reason why Prestone should cause any problems.

 

The issue of what can be safely substituted for the Toyota SLLC has been discussed a few times previously on PriusChat.... For example:

http://priuschat.com/forums/gen-ii-...e-troubleshooting/55743-inverter-coolant.html
where nthach stated: "Zerex now makes a coolant that is based on POAT chemistry that Toyota is using. Problem is, it's hard to find. DO NOT, under ANY circumstance use a "all makes/all models" coolant like Peak Long Life/Prestone/SuperTech or conventional green/silicated OAT coolants like Zerex/Peak green or G-05"

Regarding DexCool, a quick Google search turns up:
Dex-Cool GM Coolant in 2005 Pontiac Vibe? - DoItYourself.com Community Forums
in which one poster stated:
"When dexcool first came out...... it couldn't stand air in the system (still can't, its why they switched em to pressurized overflows) which makes it turn brown..
Can't stand being mixed with regular coolant (which can sludge it, something nobody knew about at first, so your regular shmoe would top off with whatever)"

 

Toyota WS for trans is usually for sale on ebay, usually beating the dealer price after shipping. I would stick to the toyota ws but some say redline D6 is doing well for them. I second the Prestone is fine opinion, but again if one wants to keep it oe, don't use it. I don't believe the brands don't mix, every company makes a point of saying they do mix. I don't second the opinion of driving it till it leaks at the water pump. That is not for me, the water pump is cheap, the engine block and head aren't.

 

Here's an interesting thread about Toy Long Life coolant:
Exact ingredients in Toyota red coolant - YotaTech Forums

I don't agree on not touching the Inverter coolant. I noticed at 20,000 what appeared to be salts or lack of better term dust on the inside of the cap of the Inverter bottle. There's some corrosion going on there most likely aluminum. Which is what the Inverter has for its big heat sink internally. I abated it somewhat using a good anti aluminum corrosion product I have experience with and have not seen anymore dust in the last 10,000 miles but it has made me push up OEM coolant replacement at 50,000 miles.

And not maintaining the engine cooling system and driving till the water pump fails is not that good either. Coolant replacement is not hard nor expensive and now most auto parts stores will loan you a mini vac to purge the systems. Only drawback to that is you have to have an air compressor but the mini vac is the foolproof way to change modern car coolants including the inverter.

 

I'll second that. I put in Prestone on my last coolant change.

 

Aftermarket coolants, maybe, but I'd stay with Toyota ATF. The ATF bathes the motor/generator electrical windings, and there's no guarantee that some other ATF will be compatible with their insulation for the life of the car.

 

Has anyone used the Zerex Asian coolant yet?

Valvoline.com > Products > Zerex > Antifreeze Zerex > Zerex® Asian Vehicle Antifreeze / Coolant

 

Yes, I use it in mine.

 

Did you use is to add to the factory fill or did you flush the coolant system first?

 

If it says ATF WS, then its compatible. The manual doesn't say you have to use Toyota brand.

Having said, that, I usually use Toyota branded fluids for everything except engine oil.

 

I have a 2007 Yaris. It requires HOAT coolant. HOAT is a mix of both IAT and OAT coolant. IAT is Inorganic Acid Technology, and OAT is Organic Acid Technology. HOAT is Hybrid Organic Acid Technology. The marketing designator for HOAT is GO-5. HOAT is automatically non-nitrite (the nitrite version is called NOAT). HOAT coolant is generally either orange or yellow. Orange is generally 10% recycled, and yellow is all non-recycled. But other types of antifreeze also might use those colors, such as OAT using orange.

Sure would be good customer service for Toyota to simply tell us which antifreeze brands and makes are right for which cars, rather than try to leave everyone so uninformed and unable to find out what's what they Toyota effectively seeks to create a monopoly. For instance, I have yet to see any label that says anything about amines!