AMSOIL Heavy-Duty Antifreeze and Coolant
AMSOIL Heavy-Duty Antifreeze and Coolant (ANTHD) is a fully formulated, ethylene glycol 50/50 pre-mix engine coolant built for diesel trucks, off-road equipment, agricultural tractors, mining and stationary engines, and mixed fleets that operate both heavy-duty and passenger-vehicle applications. The proprietary hybrid organic acid (HOAT) chemistry is enhanced with anti-scalant, anti-fouling, and water-pump lubrication additives, and the formula is phosphate-, nitrite-, silicate-, borate-, and amine-free.
Cylinder-liner cavitation and pitting protection
Wet-sleeve diesel engines from Cummins, Detroit Diesel, Caterpillar, Mack, Volvo, Navistar, and others depend on coolant chemistry to suppress the high-frequency vapor bubbles that pit and erode cylinder liners. AMSOIL Heavy-Duty Antifreeze and Coolant protects liners against cavitation erosion and corrosion pitting without nitrite technology, which can cause aluminum corrosion and is being phased out by a growing list of heavy-duty and automotive OEMs. Performance is qualified in the ASTM D7583 John Deere cavitation test, and in third-party industry-standard testing the cylinder liners protected by the formula show virtually no signs of cavitation.
Fully formulated chemistry, no SCAs required
The HOAT additive package is fully charged at fill, so the cooling system does not require separate supplemental coolant additives (SCAs), nitrite extenders, or test-strip top-ups for the duration of the service interval. This eliminates the maintenance window where under-treatment leads to liner pitting and over-treatment leads to silicate dropout or solder bloom, and it reduces the consumable inventory a fleet has to carry. The package meets ASTM D6210 fully formulated heavy-duty engine coolant requirements.
Corrosion protection for mixed-metal cooling systems
Cooling systems combine aluminum heads and water pumps with cast-iron blocks, copper and brass radiator and heater cores, lead-tin solder joints, and steel hardware. Third-party tests show AMSOIL antifreeze and coolant achieves nearly perfect scores in ASTM corrosion and erosion testing on cast aluminum cylinder heads, steel, copper, solder, brass, and cast iron and aluminum water pumps. Cast-iron and copper plate corrosion is qualified through the ASTM D2570 simulated service corrosion test, where plates protected by the formula show virtually no signs of corrosion.
Anti-scale design and water-pump lubrication
The proprietary chemistry omits the phosphate, nitrite, silicate, borate, and amine compounds responsible for almost all scaling issues in cooling systems, and the formula virtually eliminates scaling problems caused by inhibitor precipitation when pH drifts or incompatible coolants are mixed. The additive system also lubricates the water-pump seal interface, which extends seal life under heavy-duty duty cycles. Together this protects radiator tubes, heater cores, EGR coolers, and water-pump faces from scale buildup that would otherwise compromise heat transfer.
Heat transfer, freeze, and boil-over performance
The 50/50 pre-mix uses high-purity water, which delivers consistent heat transfer compared to mixing concentrate with hard or unfiltered tap water. Freeze protection extends to -34 degrees F (-37 degrees C), and boil-over protection reaches up to 265 degrees F (129 degrees C) with a properly functioning 15 psi radiator cap. Compatibility extends to all ethylene and propylene antifreeze and coolant colors, as well as the plastics and elastomers, hoses, and gaskets found in cooling systems.
Recommended applications and service intervals
AMSOIL Heavy-Duty Antifreeze and Coolant is the first-fill choice for heavy-duty diesel and off-road equipment, and it is also the best option for mixed fleets running both passenger-vehicle and heavy-duty applications that want to standardize on one coolant. The formula is suitable for use in engines requiring any of the following industry, OEM, and trade-association specifications.
- ASTM D3306, D6210, D7583, and D7820, plus TMC RP329B, TMC RP338, and AS/NZS 2108.2004 Type A.
- Heavy-duty diesel: Cummins 14603 and 3666132, Detroit Diesel 7SE 298 and 93K217, Mack 014GS17004 and 014GS17009, Volvo Heavy Truck, Navistar International CEMS B-1 Type III-A, MAN 324 NF, MTU MTL 5048, Scania TB1451, and MB DBL 7700 / MB-Approval 325.3.
- Truck and equipment OEMs: Freightliner 48-22880, Kenworth RO26-170-97, PACCAR CS0185, Peterbilt 8502.002, DAF MAT 74002, GM Heavy Truck, Case New Holland, and JIS K2234.
- Heavy-duty and off-road service life is up to 1,000,000 miles (1,609,344 km), 20,000 hours, or 8 years, whichever comes first. In non-heavy-duty (passenger car and light truck) service, the drain interval is 150,000 miles (241,000 km) or 5 years, whichever comes first.
Do not add water to the pre-mix. Do not remove the radiator cap when the engine is hot. Mixing propylene-glycol and ethylene-glycol formulations can make freeze-point prediction unreliable, and a system flush at the next convenient interval is recommended after any unavoidable cross-glycol top-off. Verify the engine and equipment specification with the AMSOIL Vehicle Lookup Guide and the AMSOIL Coolant Guide before draining and refilling.
Typical technical properties
| Property | Value |
|---|
| Glycol type | Ethylene glycol |
| Concentration | 50/50 pre-mix with high-purity water |
| Inhibitor chemistry | Hybrid organic acid (HOAT), fully formulated |
| Phosphate, nitrite, silicate, borate, amine | Free of all five |
| Boil-over protection (15 psi cap) | Up to 265 degrees F (129 degrees C) |
| Freeze protection | -34 degrees F (-37 degrees C) |
| Heavy-duty service life | 1,000,000 miles (1,609,344 km), 20,000 hours, or 8 years |
| Non-heavy-duty service life | 150,000 miles (241,000 km) or 5 years |
| Industry specifications | ASTM D3306, D6210, D7583, D7820; TMC RP329B, RP338; AS/NZS 2108.2004 Type A |
Order AMSOIL Heavy-Duty Antifreeze and Coolant
Available package sizes are the gallon jug (ANTHD1G-EA), case of four gallon jugs (ANTHD1G-CA), 55 gallon drum (ANTHD55-EA), and 275 gallon tote (ANTHD27-EA). Every gallon ships ready to install with no dilution required. AMSOIL products are backed by the AMSOIL Limited Liability Warranty. Use the AMSOIL Vehicle Lookup Guide to confirm application match and the AMSOIL Coolant Guide to compare passenger-car, heavy-duty, and Dominator Coolant Boost options before ordering. Order Now.
Customer reviews
Works great
It runs cooler worth every dollar
By Sean from Utah on May 12, 2026.
Would recommend this to a friend.
Just what my tractor needed
This is just what my Kubota tractor called for. I installed a block heater so I had to drain the coolant that was in there. This was just the ticket to replace the old coolant.
By Rex from NE Montana on January 22, 2026.
Would recommend this to a friend.
6.0 powerstroke
Everyone knows 6.0 powerstrokes are picky when it comes to coolant and oil. When my local stores stopped carrying silicate and nitrate free coolant I was stumped on what to buy until I found this. It meets every mark for what my truck wants and needs. I’m pleased with this coolant!
By Sam from Ohio on January 18, 2026.
Would recommend this to a friend.
Read all 38 reviews
Frequently asked questions
Does AMSOIL Heavy-Duty Antifreeze and Coolant require supplemental coolant additives or nitrite top-ups?
No. The formula is fully formulated to ASTM D6210 with a hybrid organic acid (HOAT) inhibitor system enhanced with anti-scalant, anti-fouling, and water-pump lubrication additives. No SCAs, nitrite extenders, or test-strip top-ups are required for the rated service life, and the chemistry suppresses cylinder-liner cavitation without the aluminum corrosion risk associated with nitrite technology.
Which heavy-duty engines and OEM coolant specs does this product cover?
The product is suitable for engines requiring ASTM D3306, D6210, D7583, or D7820, plus TMC RP329B, TMC RP338, and AS/NZS 2108.2004 Type A. OEM-specific approvals include Cummins 14603 and 3666132, Detroit Diesel 7SE 298 and 93K217, Mack 014GS17004 and 014GS17009, Volvo Heavy Truck, Navistar International CEMS B-1 Type III-A, MAN 324 NF, MTU MTL 5048, Scania TB1451, MB DBL 7700, MB-Approval 325.3, Freightliner 48-22880, Kenworth RO26-170-97, PACCAR CS0185, Peterbilt 8502.002, DAF MAT 74002, GM Heavy Truck, Case New Holland, and JIS K2234.
How long can the coolant stay in service before a flush and refill?
In heavy-duty and off-road applications, protection is rated for up to 1,000,000 miles (1,609,344 km), 20,000 hours, or 8 years, whichever comes first. When the same coolant is run in non-heavy-duty (passenger car and light truck) applications, the drain interval is 150,000 miles (241,000 km) or 5 years, whichever comes first.
Is it compatible with other coolant colors already in the system?
The formula is compatible with all ethylene and propylene antifreeze and coolant colors, as well as the plastics, elastomers, hoses, and gaskets found in cooling systems. Mixing propylene-glycol and ethylene-glycol formulations can make freeze-point prediction unreliable, so a complete cooling-system flush at the next convenient service interval is recommended whenever cross-glycol top-off has occurred.
Can it be diluted with water, or used as a concentrate?
This product ships as a 50/50 pre-mix with high-purity water and should not be further diluted. Adding tap or distilled water lowers freeze and boil-over protection and dilutes the inhibitor charge, which compromises corrosion, cavitation, and scale protection.
What is the freeze and boil-over protection rating?
Freeze protection extends to -34 degrees F (-37 degrees C). Boil-over protection reaches up to 265 degrees F (129 degrees C) when paired with a properly functioning 15 psi radiator cap.
Will it work in a 6.0L Power Stroke, Cummins, Duramax, or other diesel pickup that requires nitrite-free coolant?
Yes. The formula is phosphate-, nitrite-, silicate-, borate-, and amine-free and meets the ASTM and OEM specifications most diesel pickup manufacturers call out. Confirm the exact spec required by the vehicle through the AMSOIL Vehicle Lookup Guide or the owner manual before draining the system.
