Valvoline Zerex Asian Vehicle Red antifreeze concentrate

This is Valvoline's red, silicate-free, phosphated HOAT antifreeze for vehicles whose factory fluid is pink or red, which above all means Toyota, Lexus and Scion. Those are exactly the three names printed on the bottle. The product is a concentrate and must be diluted before filling.

Valvoline Zerex Asian Red antifreeze concentrate, front of the bottle

Photographs come from the manufacturer's official materials.

Who the red is for

If the fluid in your expansion tank is pink or red, this is your product. In practice that means Toyota, Lexus and Scion, including the hybrids: Prius, Aqua, Camry Hybrid, Corolla Hybrid, C-HR, RAV4, Alphard, Harrier, Lexus RX 450h, NX 300h and CT 200h.

Toyota hybrids run two cooling circuits, one for the engine and one for the inverter, and the same pink type is specified for both.

If the tank holds blue fluid, your product is Zerex Asian Blue, and if it holds green, it is Zerex Asian Green.

How it differs from the blue

Chemically, almost nothing. All three are the same patented formulation family (US 5,454,967), all three are phosphated HOATs on an ethylene glycol base, and all three data sheets state plainly that they contain no silicates, borates, 2-EHA, amines or nitrites.

The difference is which factory colour they match. The blue is for Subaru, Honda and blue-filled Nissans, the green is for Hyundai, Kia, Mazda and Mitsubishi, and the red is for Toyota, Lexus and Scion.

The laboratory results are identical too: 10 out of a required 8 in the aluminium pump cavitation test, 0.1 mg/cm²/week against a 1.0 limit for hot-surface corrosion, and 0 mg aluminium weight loss in ASTM D1384.

A concentrate, so you set the level of protection

The red is a concentrate as well. One bottle, 1 US gallon (3.78 L) concentrate, yields 7.5 litres of ready-to-use coolant at 50/50, which covers a full fill on a Prius, an Aqua and most Toyotas.

The mixing rule is the same: concentrate first into a clean container, then water, mix thoroughly, and only then fill. Never pour neat concentrate straight into the system.

For the exact ratio see our dilution calculator.

Product photos

Valvoline Zerex Asian Red antifreeze concentrate, back label with dilution instructions

Dilution chart

Antifreeze 50% Freeze point −36 °C Boil point 128 °C Standard, equivalent to factory fill

AntifreezeFreeze point

Antifreeze	Water	Freeze point	Boil point	When to use
33%	67%	≈ −18 °C	≈ 125 °C	Weakest useful mix, for a mild winter
40%	60%	−24 °C	126 °C	The minimum on the manufacturer's chart
50%	50%	−36 °C	128 °C	Standard, equivalent to factory fill
60%	40%	−48 °C	133 °C	High altitude, severe winter
70%	30%	−67 °C	135 °C	Maximum protection, more is not better

The 33 per cent row is not on the manufacturer's chart and comes from the general ethylene glycol curve. Every other row is from the official data sheet. Below 40 per cent the inhibitor concentration also drops, so 33 per cent is for mild winters only.

Technical data

Part number	910234
Colour	Red / წითელი
Base	Ethylene glycol
Technology	HOAT, phosphated organic acid
Glycols	91.0 mass %
Corrosion inhibitors	7.0 mass %
Water	2.0 mass %
pH (50% v/v)	8.4
Reserve alkalinity (RA)	12
Specific gravity 60/60 °F	1.1450
Flash point	121 °C (250 °F)
Silicon as Si	< 10 ppm
Borates as B	< 10 ppm
Chloride	< 10 ppm
Ash content	< 5 mass %
Boiling point, undiluted	175 °C (347 °F)
Storage stability	5 years

What it does not contain and why that matters

SilicatesSilicate drops out as an abrasive gel that grinds the water-pump seal.
BoratesBorate accelerates aluminium corrosion, which is why Asian OEMs dropped it.
2-EHA2-ethylhexanoic acid is a plasticiser that softens gaskets and plastics. It is present in many cheap “universal” coolants.
AminesAmines can form nitrosamines together with nitrites.
NitritesNot needed in a passenger-car aluminium system and attacks solder.

Laboratory test results

Aluminium water pump cavitation (ASTM D2809, 100 h)

Limit: Minimum 8
Actual: 10, a perfect score

10 means “perfect” and 1 means “perforated”. A direct measure of water-pump survival.

Hot surface aluminium corrosion (ASTM D4340)

Limit: Max 1.0 mg/cm²/week
Actual: 0.1 mg/cm²/week, ten times better than the limit

This test targets the hottest point of an aluminium head, exactly where aluminium engines fail.

Repassivation of aluminium surfaces

Limit: > −400 mV
Actual: +447 mV

Means a damaged aluminium surface rebuilds its own protective film.

Foaming (ASTM D1881)

Limit: Max 150 ml
Actual: 80 ml

Foam is air, and air does not carry heat. It also makes the pump cavitate.

OEM

Hyundai / Kia MS591-08
Subaru
Honda / Acura
Nissan / Infiniti
Toyota / Scion / Lexus
Mazda
Mitsubishi
Suzuki
Isuzu
Daihatsu
Dae Woo

ASTM D3306
ASTM D4985
JIS K 2234-1994
Ford WSS-M97B55-A
Mitsubishi ES 64-217
Federal Specification A-A-870A

All technical figures come from Valvoline's official product information sheet. Official technical data sheet (PDF) · Manufacturer page

Frequently asked questions

Can I mix the red, the blue and the green?

We would not recommend it. All three are Asian HOATs, but they are three different products, and after mixing you can never tell what is in the system. Choose the one that matches your car's factory colour.

My Prius has pink fluid. Can I top up with the red?

If the system holds Toyota's factory pink SLLC and the level has dropped, the red belongs to the same family and topping up is reasonable. A complete flush is still the right move if the fluid is more than five years old.

Is it genuine?

Yes, we bring it in from the United States. The part number 910234 and the label correspond to Valvoline's official data sheet, which is linked on this page.