2003 Isuzu NPR Cooling System Parts

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. Read more

14 Coolant / Antifreeze parts are listed for the 2003 Isuzu NPR, from PRESTONE, PEAK, VALVOLINE and 1 other brand. FVP MV5050GAL carries the "Popular" badge. All of them fit every engine offered in the 2003 NPR.

The Compatible With All Colors section lists 1 option from PRESTONE — grouped under the catalog's "Compatible With All Colors" designation — the notes column spells out what sets them apart. PRESTONE AF3055 is listed in this group.

In the Economy grade, FVP, PEAK, PRESTONE and 1 other brand supply 4 parts: the catalog's value-priced group. A representative part number is FVP MV5050GAL.

The Heavy Duty section lists 3 options from PRESTONE and PEAK — rated for severe service. PEAK FXA1GAL is listed in this group.

The Premium section lists 4 options from PRESTONE and PEAK — a step above OE specification in materials, tolerances or warranty terms. PRESTONE AF2100 is listed in this group.

The Standard Replacement section lists 2 options from VALVOLINE — built to original-equipment specification. VALVOLINE ZXEL1 is listed in this group.

This table covers the overflow / expansion tanks that hold extra coolant. Read more

This group shows a single part: DORMAN 6035603.

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. Read more

This group shows a single part: DORMAN 9241059.

This table covers the adapters used to pressure-test this cooling system. Read more

4 Cooling System Tester Adapter parts are listed for the 2003 Isuzu NPR, from MOTORAD, GATES and STANT. 3 parts fit every engine; the other 1 is engine-specific.

This group includes GATES 31428, MOTORAD 3121 and MOTORAD 3122 and the remaining parts above.

This table covers the intercoolers that cool turbo or supercharger charge air. Read more

3 Intercooler parts are listed for the 2003 Isuzu NPR, from CSF, GPD and SPECTRA PREMIUM.

Listed part numbers: CSF 6051, GPD 2711272 and SPECTRA PREMIUM 44010703.

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. Read more

10 Radiator parts are listed for the 2003 Isuzu NPR, from GPD, CSF, OSC and 3 other brands. CSF 3220 carries the "Popular" badge.

Economy: 3 parts, from GPD and ULTRA-POWER. A representative part number is GPD 9243220.

The Heavy Duty (All Metal Construction) section lists 1 option from CSF — rated for severe service. CSF 3220 is listed in this group.

The Standard Replacement section: 4 options from OSC, CSF and SPECTRA PREMIUM. CSF 3210 is listed in this group.

2 ungrouped parts are not assigned to a grade, with the same engine-level match.

This table covers the caps that hold system pressure at the radiator or reservoir neck. 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. Read more

7 Radiator Cap parts are listed for the 2003 Isuzu NPR, from GATES, MOTORAD, CALORSTAT and 2 other brands. MOTORAD T16R carries the "Popular" badge. 5 parts fit every engine; the other 2 are engine-specific.

The Locking Replacement section lists 3 options from CALORSTAT, GATES and MOTORAD — grouped under the catalog's "Locking Replacement" designation — the notes column spells out what sets them apart. CALORSTAT RC0212 is listed in this group.

The Standard Replacement section: 4 options from MOTORAD, SKP, CSF and 1 other brand. MOTORAD T16R is listed in this group.

Part numbers include MOTORAD T16R, CALORSTAT RC0212 and GATES 31534, among others listed above.

This table covers the Radiator Fan blades. Typical signs include chatter, streaks, or a skip at the top of the stroke. Confirm left and right lengths in the notes — they are often different. Read more

2 Radiator Fan Blade parts for the 2003 Isuzu NPR come from 2 brands — DORMAN and GPD.

Listed part numbers: DORMAN 6205603 and GPD 2812352.

This table covers the upper, lower and connecting hoses between radiator, engine and reservoir. Typical signs include swelling, cracks, a soft spot, or a leak at a clamp. Replace adjacent aged hoses while the system is drained — they share the same heat cycle. Read more

15 Radiator Hose parts for the 2003 Isuzu NPR come from 4 brands — CONTINENTAL, GATES, DAYCO and 1 other brand. The "Popular" part is CONTINENTAL 62699.

This table covers the senders that report coolant temperature to the gauge or ECU. Typical signs include a gauge that sits on empty or overheat, or a lamp that does not match what the engine is doing. Rule out the cluster and the wiring before replacing the sender. Read more

One part is listed for the 2003 Isuzu NPR — DORMAN 926016.

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. Read more

27 Thermostat parts for the 2003 Isuzu NPR come from 4 brands — MOTORAD, CALORSTAT, GATES and 1 other brand. The "Popular" part is MOTORAD 5265195. Heavy Duty, Performance, Premium and Standard Replacement are all represented, and Standard Replacement alone accounts for 14 parts.

This table covers the housings and outlets the thermostat sits in. Read more

2 Thermostat Housing / Water Outlet parts for the 2003 Isuzu NPR come from 2 brands — DORMAN and MOTORAD.

The Economy section: 1 option from DORMAN. DORMAN 902754 is listed in this group.

Standard Replacement: 1 part, from MOTORAD. A representative part number is MOTORAD CH5169.

Part numbers include DORMAN 902754 and MOTORAD CH5169.

This table covers the pumps that circulate coolant through the block and radiator. Typical signs include coolant at the weep hole, pulley play, or a growl from the front of the engine. Replace the thermostat and refill with the specified coolant whenever the pump comes off. Read more

12 Water Pump parts for the 2003 Isuzu NPR come from 5 brands — FVP, US MOTOR WORKS, GATES and 2 other brands. The "Popular" part is GATES 42239HD.

The Economy section: 5 options from FVP, US MOTOR WORKS and SKP. FVP US8969 is listed in this group.

The High Volume / Pressure section lists 3 options from GATES, FVP and US MOTOR WORKS — grouped under the catalog's "High Volume / Pressure" designation — the notes column spells out what sets them apart. GATES 42239HD is listed in this group.

Standard Replacement: 4 parts, from GMB, GATES and FVP. A representative part number is GATES 43315.

This table covers the Water Pump Stud kits. Read more

This group shows a single part: DORMAN 902804.