30 Cooling system parts are listed for the 2021 International HX, in 8 part types, covering both the 12.4L L6 DIESEL Turbocharged and the 14.9L L6 DIESEL Turbocharged. Each one has a brand, a manufacturer part number and notes that say where it fits.
The cooling system system on the 2021 International HX keeps operating temperature in the narrow band the engine was designed for, from radiator and water pump to thermostat and hoses. The largest groups are Coolant / Antifreeze (9 parts), Thermostat (7 parts) and Radiator (5 parts). The other 5 part types cover the remaining 9 parts.
The 2021 International HX was sold with both the 12.4L L6 DIESEL Turbocharged and the 14.9L L6 DIESEL Turbocharged. 16 parts fit every engine; the other 14 are engine-specific. Each part shows which engine(s) it fits.
11 brands supply cooling system parts for the 2021 International HX, led by MOTORAD (5 parts), VALVOLINE (4 parts) and PRESTONE (3 parts), plus 8 more brands. Quality grades include Standard Replacement, Heavy Duty and Economy.
A "Popular" badge means the source catalog flagged the part as frequently chosen for the 2021 International HX. 5 parts have it, including VALVOLINE ZXG051 (Coolant / Antifreeze) and SPECTRA PREMIUM 20013560P (Radiator). Each part number opens a page with every vehicle that part fits.
Coolant / Antifreeze
Economy
| Brand | Part Number | Markets | Notes | Buy |
|---|---|---|---|---|
| VALVOLINE Fits: all 2021 HX engines | 719009 | 🇺🇸 US 🇨🇦 CA | Multi-Vehicle Yellow1 Gallon | View on Amazon |
Heavy Duty
| Brand | Part Number | Markets | Notes | Buy |
|---|---|---|---|---|
| VALVOLINE Popular Fits: all 2021 HX engines | ZXG051 | 🇺🇸 US 🇨🇦 CA | G05 Yellow1 Gallon | View on Amazon |
| PEAK Fits: all 2021 HX engines | FCA1GAL | 🇺🇸 US 🇨🇦 CA | Fleet Charge1 Gallon | View on Amazon |
| PEAK Fits: all 2021 HX engines | FXA1GAL | 🇺🇸 US 🇨🇦 CA | Final Charge Global1 Gallon | View on Amazon |
| PRESTONE Fits: all 2021 HX engines | AFC10000 | 🇺🇸 US 🇨🇦 CA | Command ESi PrechargedPurple | View on Amazon |
| PRESTONE Fits: all 2021 HX engines | AFC13000 | 🇺🇸 US 🇨🇦 CA | Command COR-Guard Nitrite Free-Noat Extended Life CoolantRed | View on Amazon |
| PRESTONE Fits: all 2021 HX engines | AFC12100 | 🇺🇸 US 🇨🇦 CA | Command Nitrite Free Extended Life CoolantYellow Nitrite Free OAT | View on Amazon |
| VALVOLINE Fits: all 2021 HX engines | 846439 | 🇺🇸 US 🇨🇦 CA | HD Nitrite Free Extended Life Yellow1 Gallon | View on Amazon |
Standard Replacement
| Brand | Part Number | Markets | Notes | Buy |
|---|---|---|---|---|
| VALVOLINE Popular Fits: all 2021 HX engines | ZX001 | 🇺🇸 US 🇨🇦 CA | Original Green1 Gallon | View on Amazon |
This table covers the engine coolants and antifreeze formulations specified for this cooling system. Typical signs include a rising temperature gauge, rusty or sludged coolant, or a heater that blows cold. Use the chemistry named in the notes. Mixing silicate, OAT and HOAT formulas can gel in the radiator.
9 Coolant / Antifreeze parts are listed for the 2021 International HX, from VALVOLINE, PRESTONE and PEAK. VALVOLINE ZXG051 carries the "Popular" badge. All of them fit every engine offered in the 2021 HX.
In the Economy grade, VALVOLINE supplies 1 part: the catalog's value-priced group. A representative part number is VALVOLINE 719009.
The Heavy Duty section lists 7 options from PRESTONE, VALVOLINE and PEAK — rated for severe service. VALVOLINE ZXG051 is listed in this group.
The Standard Replacement section lists 1 option from VALVOLINE — built to original-equipment specification. VALVOLINE ZX001 is listed in this group.
This group includes VALVOLINE ZXG051, VALVOLINE 719009 and PEAK FCA1GAL and the remaining parts above.
Coolant Filter
| Brand | Part Number | Markets | Notes | Buy |
|---|---|---|---|---|
| HASTINGS / BALDWIN Fits: 12.4L L6 DIESEL Turbocharged | LOPRI | 🇺🇸 US 🇨🇦 CA | View on Amazon |
This table covers the Coolant filters. Typical signs include restricted flow — long cranking, weak airflow, or dirty fluid after a short interval. Seat the new filter so it cannot bypass, and use the grade the notes call for.
One part is listed for the 2021 International HX — HASTINGS / BALDWIN LOPRI.
Coolant Reservoir Cap
| Brand | Part Number | Markets | Notes | Buy |
|---|---|---|---|---|
| GATES Fits: all 2021 HX engines | 31405 | 🇺🇸 US 🇨🇦 CA | OE Type | View on Amazon |
| MOTORAD Fits: 14.9L L6 DIESEL Turbocharged | T39 | 🇺🇸 US 🇨🇦 CA | Standard | View on Amazon |
This table covers the caps on the overflow / expansion tank. Typical signs include a leak at the neck, a cap that will not hold pressure, or a missing tether. Match the pressure rating or thread in the notes — radiator, reservoir and fuel caps are not interchangeable.
2 Coolant Reservoir Cap parts for the 2021 International HX come from 2 brands — GATES and MOTORAD. 1 part fits every engine; the other 1 is engine-specific.
Part numbers include GATES 31405 and MOTORAD T39.
Hose Clamp
| Brand | Part Number | Markets | Notes | Buy |
|---|---|---|---|---|
| DORMAN Fits: all 2021 HX engines | 9044000 | 🇺🇸 US 🇨🇦 CA | 1.75" DiameterCoolant | View on Amazon |
This table covers the Hose clamps.
One part is listed for the 2021 International HX — DORMAN 9044000.
Intercooler Air Hose / Pipe
| Brand | Part Number | Markets | Notes | Buy |
|---|---|---|---|---|
| CONTINENTAL Fits: 12.4L L6 DIESEL Turbocharged | 57504 | 🇺🇸 US 🇨🇦 CA | Convoluted Charge Air | View on Amazon |
| CONTINENTAL Fits: all 2021 HX engines | 57513 | 🇺🇸 US 🇨🇦 CA | Convoluted Charge Air | View on Amazon |
| GATES Fits: 12.4L L6 DIESEL Turbocharged | 26200 | 🇺🇸 US 🇨🇦 CA | Turbocharger Hose (Ring-Retained)Straight Hose | View on Amazon |
This table covers the Intercooler Air Hose pipes.
3 Intercooler Air Hose / Pipe parts are listed for the 2021 International HX, from CONTINENTAL and GATES. 1 part fits every engine; the other 2 are engine-specific.
Listed part numbers: CONTINENTAL 57504, CONTINENTAL 57513 and GATES 26200.
Radiator
Economy
| Brand | Part Number | Markets | Notes | Buy |
|---|---|---|---|---|
| GPD Fits: all 2021 HX engines | 9282773 | 🇺🇸 US 🇨🇦 CA | with 34 In Core Heightwithout Frame | View on Amazon |
| GPD Fits: all 2021 HX engines | 9282774 | 🇺🇸 US 🇨🇦 CA | with Original Equipment (OE) # 2516107C91with 34 In Core Height | View on Amazon |
Standard Replacement
| Brand | Part Number | Markets | Notes | Buy |
|---|---|---|---|---|
| SPECTRA PREMIUM Popular Fits: all 2021 HX engines | 20013560P | 🇺🇸 US 🇨🇦 CA | Aluminum Core with Plastic Tanks | View on Amazon |
| SPECTRA PREMIUM Fits: all 2021 HX engines | 20013560 | 🇺🇸 US 🇨🇦 CA | Aluminum Core / Aluminum Tank | View on Amazon |
| SPECTRA PREMIUM Fits: 14.9L L6 DIESEL Turbocharged | 20013562P | 🇺🇸 US 🇨🇦 CA | Aluminum Core with Plastic Tanks | View on Amazon |
This table covers the radiators that dump engine heat to airflow through the core. Typical signs include overheating in traffic, a wet core, or coolant that disappears with no puddle. Replace the cap if it cannot hold the rated pressure, and bleed the system after the swap.
5 Radiator parts are listed for the 2021 International HX, from SPECTRA PREMIUM and GPD. SPECTRA PREMIUM 20013560P carries the "Popular" badge. 4 parts fit every engine; the other 1 is engine-specific.
Economy: 2 parts, from GPD. A representative part number is GPD 9282773.
The Standard Replacement section: 3 options from SPECTRA PREMIUM. SPECTRA PREMIUM 20013560P is listed in this group.
Part numbers include SPECTRA PREMIUM 20013560P, GPD 9282773 and GPD 9282774, among others listed above.
Thermostat
Heavy Duty
| Brand | Part Number | Markets | Notes | Buy |
|---|---|---|---|---|
| GATES Popular Fits: 14.9L L6 DIESEL Turbocharged | 34148 | 🇺🇸 US 🇨🇦 CA | Heavy-Duty | View on Amazon |
Standard Replacement
| Brand | Part Number | Markets | Notes | Buy |
|---|---|---|---|---|
| MOTORAD Popular Fits: 14.9L L6 DIESEL Turbocharged | 406190 | 🇺🇸 US 🇨🇦 CA | Includes Seal | View on Amazon |
| CALORSTAT Fits: 14.9L L6 DIESEL Turbocharged | THS1910582 | 🇺🇸 US 🇨🇦 CA | PerformanceDoes Not Include Seal | View on Amazon |
| CALORSTAT Fits: 14.9L L6 DIESEL Turbocharged | THS1910588 | 🇺🇸 US 🇨🇦 CA | Does not include seal | View on Amazon |
| MOTORAD Fits: 14.9L L6 DIESEL Turbocharged | 406160 | 🇺🇸 US 🇨🇦 CA | Includes Seal | View on Amazon |
| MOTORAD Fits: 14.9L L6 DIESEL Turbocharged | 407825 | 🇺🇸 US 🇨🇦 CA | 225 Degrees Ffor Engine Oil Cooler System | View on Amazon |
| MOTORAD Fits: 14.9L L6 DIESEL Turbocharged | 406180 | 🇺🇸 US 🇨🇦 CA | Includes Seal | View on Amazon |
This table covers the thermostats that open the coolant circuit at the specified temperature. Typical signs include slow warm-up, a gauge that climbs in traffic, or heat that never quite arrives. Replace the housing gasket with the thermostat and bleed the system so a trapped air pocket does not cook the new part.
7 Thermostat parts for the 2021 International HX come from 3 brands — MOTORAD, CALORSTAT and GATES. The "Popular" part is GATES 34148.
Heavy Duty: 1 part, from GATES. A representative part number is GATES 34148.
Standard Replacement: 6 parts, from MOTORAD and CALORSTAT. A representative part number is MOTORAD 406190.
Listed part numbers: GATES 34148, MOTORAD 406190 and CALORSTAT THS1910582, plus the other parts above.
Thermostat / Thermostat Housing / Water Outlet Seal
| Brand | Part Number | Markets | Notes | Buy |
|---|---|---|---|---|
| DORMAN Fits: 14.9L L6 DIESEL Turbocharged | 6745003G | 🇺🇸 US 🇨🇦 CA | Housing to Flange | View on Amazon |
| DORMAN Fits: 14.9L L6 DIESEL Turbocharged | 6745008G | 🇺🇸 US 🇨🇦 CA | Housing to Cylinder Head | View on Amazon |
This table covers the seals at the thermostat housing and water outlet. Typical signs include a wet housing, a drip after sitting, or fluid flung off a rotating shaft. Fix the surface the seal rides on. A new seal on a grooved shaft will leak again.
DORMAN supplies both parts for the 2021 International HX.
Listed part numbers: DORMAN 6745003G and DORMAN 6745008G.
Buying Cooling System Parts for a 2021 International HX
On this vehicle, the cooling system system keeps operating temperature in the narrow band the engine was designed for, from radiator and water pump to thermostat and hoses.
- Match the engine first. Some cooling system parts fit every engine; others are engine-specific. Each row shows which engine(s) it fits.
- Read the notes on each row for position, trim and spec qualifiers before you order.
- Where labor overlaps, replace the thermostat and refill with fresh coolant whenever you change a water pump or radiator; original hoses on an older vehicle are on borrowed time.
- Cross-reference the manufacturer part number against your old part or a service-manual listing.
Start with the largest groups on this page: Coolant / Antifreeze and Thermostat .
Frequently Asked Questions
How many cooling system parts fit the 2021 International HX?
Our catalog currently lists 30 cooling system parts for the 2021 International HX across 8 subcategories and 11 brands, covering both the 12.4L L6 DIESEL Turbocharged and the 14.9L L6 DIESEL Turbocharged. Each part is matched to the engine(s) it fits.
Do cooling system parts differ between 2021 International HX engines?
Some do. 16 parts fit every engine; the other 14 are engine-specific. Each row (and the filter at the top) shows which. If you're unsure which engine you have, check the emissions label under the hood or the 8th character of your VIN.
What are the signs of cooling system problems on a 2021 International HX?
Common symptoms include a rising temperature gauge in traffic, sweet-smelling steam, crusty deposits around hose clamps, or a heater that blows cold. If you notice any of these, identify the affected subcategory above and cross-reference the part numbers listed.
What should I replace at the same time?
Where labor overlaps, replace the thermostat and refill with fresh coolant whenever you change a water pump or radiator; original hoses on an older vehicle are on borrowed time.
What do the market flags (US, CA, MX) on each part mean?
They show the market for which the manufacturer published application data for that part — where the vehicle was first sold, not where the part was made. If your 2021 International HX was originally sold in the US, the safest choice is a part marked for the US market.
How do I make sure a part fits my 2021 International HX?
First match the engine — each row shows which engine(s) the part fits. Then replace coolant with the exact specification the manufacturer calls for — mixing chemistries can gel and block small passages. The notes column carries position and trim qualifiers where they apply.
Other Parts for the 2021 International HX
Cooling System Parts for Other International HX Years
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