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2003 Infiniti FX35/45

Factory specifications, fluid capacities, torque values, EPA fuel economy and the federal safety record for the 2003 FX35/45.

Transmission Automatic (S5)

The 2003 Infiniti FX35/45 arrived as the model's inaugural year, pairing a five-speed automatic transmission with EPA ratings of 15 city, 22 highway, and 17 combined mpg and a 5.0-quart oil capacity spec calling for 5W-30 API SL. Across 60 total owner complaints and 10 recalls, air bags emerged as the top complaint area — a notable flag for a vehicle's primary safety system. Within the model's broader 2004–2008 complaint history, the 2003's count sits below the 2004 peak of 141 and above the 2008 low of 37, placing this launch year within an early-generation reliability arc that trended toward improvement as subsequent years accumulated fewer complaints.

Model year2008 2007 2006 2005 2004 2003

Quick specs

Fluid capacities, tune-up values and fuel economy at a glance.

Engine oil capacity5.0 qtOEM · verified

Engine oil type5W-30 API SLOEM · verified

Lug nut torque80 ft-lbsOEM · verified

EPA fuel economy15/22/17 mpgEPA · verified

Fitment & sizes

Replacement part sizes and factory part numbers — battery, bulbs, filters and belts.

From the factory this vehicle uses a BCI 35 · 490 CCA battery, OE oil filter 1520865F0E. Note the factory front wiper blades is now discontinued — plan on a superseded or quality aftermarket equivalent, which the part pages below list where known. Each part links to every other vehicle that shares it, so a part you already stock may fit more of your fleet than you'd expect.

Battery groupBCI 35 · 490 CCAOEM · verified

Tire sizeP265-50R20OEM · verified

Wheel / rim8-JJ inOEM · verified

OE service part numbers OEM · verified

Engine oil filter	1520865F0E
Engine air filter	16546V0100
Spark plug	224015M015 alt 224015M014
Front wiper blades	288901CA1A discontinued · alt 288901CA0A
Serpentine belt	11920AG900 alt 117204P102
Thermostat	1305031U00 alt 212004W01B
Cabin air filter	27277VP01A

Full specifications

Engine, drivetrain, dimensions and economy.

Engine & drivetrain NHTSA vPIC

Transmission

Automatic (S5)

Ratings & economy EPA / vPIC

EPA city / highway / combined	15 / 22 / 17 mpg
Drivetrain	Rear-Wheel Drive
Recommended fuel	Regular Gasoline

Service quick specs OEM factory data

Capacities, torques and tune-up values from the factory service manual.

This engine holds 5.0 qt of 5W-30 API SL engine oil, 80W-90 · GL-5 in the differential, DOT 3 brake fluid. Torque lug nuts to 80 ft-lbs, the oil drain plug to 28.0 ft-lbs. The firing order is 1-8-7-3-6-5-4-2. Note the cylinder-head bolts finish on a torque angle (torque-to-yield) — they stretch permanently and should be replaced, not reused, during any head service.

Lubricants & capacities

Brake Fluid	DOT 3
Differential Gear Oil	80W-90 · GL-5
Differential Gear Oil Capacity	1.4 Pints
Differential Gear Oil	80W-90 · GL-5
Differential Gear Oil Capacity	3.1 Pints
Engine Oil	5W-30 · API
Engine Oil Capacity	5.0 qt
Engine Oil	5W-30 · API

Engine torques

Engine Flywheel Bolts	65 ft-lbs
Engine Oil Pan Drain Plug	28.0 ft-lbs

Chassis torques

Lug Nuts	80 ft-lbs
Transfer Case Fill Plug	26.0 ft-lbs
Transfer Case Drain Plug	26.0 ft-lbs

Ignition

Cylinder Firing Order	1-2-3-4-5-6
Cylinder Firing Order	1-8-7-3-6-5-4-2
Curb Idle Speed (No Load)	750 rpm
Curb Idle Speed Variance (No Load)	50 rpm
Curb Idle Speed (No Load)	650 rpm
Curb Idle Speed Variance (No Load)	50 rpm
Spark Plug Gap	0.043 in
Spark Plug Torque	18.0 ft-lbs

Battery & A/C

Refrigerant	R134a
Refrigerant Capacity	1.21 lbs
Oil Group	PAG
Oil Type	NISSAN A/C System Oil Type S or equivalent
Oil Capacity	6.00 oz
Standard BCI Group Number	35
Standard BCI Cranking Performance	490 cca
Standard BCI Group Number	35

Service checks

Pressure Test	23 psi
Radiator Cap Pressure Relief	11-14 psi
Thermostat Opening Temperature	180 °F
Pressure Test	23 psi
Radiator Cap Pressure Relief	11-14 psi
Thermostat Opening Temperature	176-183 °F
Regulated Fuel System Pressure (Without Vacuum)	43.0 psi
Regulated Fuel System Pressure (With Vacuum)	34.0 psi

Brakes

Torque Caliper to Bracket	20 ft-lbs / 32 ft-lbs
Torque to Knuckle	116 ft-lbs / 62 ft-lbs
Minimum Pad Thickness	Front: 0.079; Rear: 0.079 in
Rotor Max Parallel Variation	0.0006 in
Rotor Runout Limit	0.0008 in / 0.002 in
Rotor Nominal Thickness From	1.102 in / 0.63 in
Rotor Nominal Thickness To	1.102 in / 0.63 in
Rotor Minimum Machining	1.024 in / 0.551 in

Multi-step torque procedures OEM · verified

Connecting Rod (Large End) Bearings — tightening sequence 1 stages

14-15 ft. lbs., Step 2: 90-95

14–15 ft. lbs

Crankshaft Pulley and/or Damper Bolts — tightening sequence 1 stages

79-36 ft. lbs., step 2: +60 degrees-66

79–36 ft. lbs

Crankshaft Pulley and/or Damper Bolts — tightening sequence 1 stages

65-72 ft. lbs., step 2: 90-96

65–72 ft. lbs

Cylinder Head — tightening sequence 4 stages

1	72.0 ft. lbs.	72 ft. lbs
2	Loosen all bolts completely in order.
3	29.0 ft. lbs.	29 ft. lbs
4	90 degrees	90 degrees

Cylinder Head — tightening sequence 4 stages

1	72.0 ft. lbs.	72 ft. lbs
2	Loosen all bolts completely in order.
3	32.0 ft. lbs.	32 ft. lbs
4	60 degrees	60 degrees

Main Bearings — tightening sequence 1 stages

24-28 ft. lbs., Step 2: 90-95

24–28 ft. lbs

Factory maintenance schedule OEM · verified

Normal service, condensed from the factory interval matrix.

Under the factory schedule, replace the engine oil and filter every 3,750 mi; spark plugs at 105,000 mi; coolant every 30,000 mi. The big-interval services (every 30,000 mi for coolant, and the transmission fluid) are the ones owners most often skip — on a lower-mileage example, assume the original fluids are still in it and check them first.

Every 3,750 mi	Engine Oil Filter (replace)
Every 7,500 mi	Engine Oil (drain & refill)
Every 15,000 mi	Accessory Drive Belt (inspect) · Axle Shaft Oil Seal (inspect) · Brake Line (inspect) · Brake Linings (inspect) · CV Joint Boot (inspect) · Cabin Air Filter (replace)
Every 30,000 mi	Emission Control System (inspect) · Engine Air Filter Element (replace) · Engine Coolant System (drain, flush & refill) · Exhaust System (Complete) (inspect) · Fuel Line (inspect) · Transfer Case Assembly (inspect fluid level)
At 60,000 mi	Accessory Drive Belt (inspect) · Engine Coolant System (drain, flush & refill)
At 105,000 mi	Engine Valves (inspect valve lash) · Spark Plugs (replace)

Reliability & federal safety record

Owner-reported issues, recalls, investigations and service bulletins on record with NHTSA — an unfiltered look at what owners actually experience.

As the inaugural model year for the Infiniti FX35/45, 2003 sits at the very beginning of the generation's reliability arc, directly preceding the peak federal complaint year of 2004 which saw 141 complaints. Across the subsequent years, complaints steadily decline from that 2004 peak down to just 37 in 2008, and recalls similarly taper off after hitting a high of 9 in 2005, indicating that early production models bore the brunt of the platform's initial growing pains. For the 2003 model specifically, federal records show primary concerns clustered around Air Bags (8 complaints) and Latches/Locks/Linkages (7 complaints), alongside Structure (5) and Electrical/Locks (4), resulting in 2 crash and 1 fire complaints. The data does not specify the root causes for these issues, but the concentration of airbag and locking mechanism complaints strongly suggests first-model-year quality control deficits. Consequently, because 2003 introduces a generation that peaks in complaints the very next year and lacks the later-year refinements, this is not a strongly recommended model year to purchase for a used buyer prioritizing long-term reliability.

Open recalls

NHTSA campaigns

Service bulletins

Manufacturer communications

ODI investigations

Office of Defects Investigation

Owner complaints

2 involved a crash · 1 a fire

Owner complaints by model year NHTSA · this generation & adjacent

’04 ’05 ’06 ’07 ’08

Owner complaints filed with NHTSA, by component

All 60 complaints on record, top 8 components.

Air Bags8

Latches/Locks/Linkages7

Structure5

Electrical System,Latches/Locks/Linkages4

Engine & Engine Cooling4

Engine3

Service Brakes, Hydraulic3

Seats3

Source: NHTSA Office of Defects Investigation complaint database.

Recalls NHTSA · verified

Showing 2 of 10 campaigns on record for this vehicle.

20V008000Air Bags:Frontal:Passenger Side:Inflator ModuleReported 09/01/2020

Nissan North America, Inc. (Nissan) is recalling certain 2001-2003 Maxima, 2002-2006 Sentra, 2002-2004 Pathfinder, 2007-2011 Versa Sedan and Versa Hatchback, 2001-2004 Infiniti I30 and I35, 2002-2003 Inifiniti QX4… Remedy: Nissan will notify owners, and dealers will replace the front passenger air bag inflators with alternate desiccated inflators, free of charge. The recall began February 12, 2020…

16V349000Air Bags:Frontal:Passenger Side:Inflator ModuleReported 24/05/2016

Nissan North America, Inc. (Nissan) is recalling certain model year 2003-2008 Infiniti FX35 and FX45, 2003-2004 Infiniti I35, 2006-2010 Infiniti M35 and M45, and 2007-2011 Nissan Versa vehicles, originally sold, or ever… Remedy: Nissan will notify owners, and dealers will replace the passenger frontal air bag inflator, free of charge. The recall began December 21, 2017. All owners should receive a second…

Technical service bulletins NHTSA · verified

Showing 5 of 86 bulletins on record with NHTSA.

Bulletin	Date	Component	Summary
ITB03-068A	2026-04-28	Air Bags	Voluntary Service Campaign ID # P3156 is no longer active. · Repair orders opened after…
ITB09-063C	2026-04-13	Structure	CERTIFICATION LABEL AND VIN PLATE REPLACEMENT SERVICE INFORMATION Because of collision…
ITB13-052E	2024-05-20	Electrical System	INTELLIGENT KEY NOT DETECTED / ENGINE WILL NOT START This bulletin has been amended. See…
ITB17-009H	2024-04-29	Visibility/Wiper	WINDOW GLASS WARRANTY INFORMATION This bulletin has been amended. See AMENDMENT HISTORY…
ITB13-007I	2024-04-29	Visibility/Wiper	REMOVING FOREIGN MATERIAL FROM THE WINDOW GLASS This bulletin has been amended. See…

Common OBD-II trouble codes

The most common OBD-II codes for this vehicle's emissions system. These are standardized SAE J2012 definitions, not vehicle-specific fault reports.

P0420

Catalyst system efficiency below threshold — Bank 1

P0300

Random / multiple cylinder misfire detected

P0171

System too lean — Bank 1

P0455

Evaporative emission system leak detected — large leak

P0128

Coolant thermostat below regulating temperature

P0442

Evaporative emission system leak detected — small leak

VIN tools

Decode factory build data for a specific vehicle by VIN.

VIN

Decode a VIN to confirm the transmission and build data for a specific FX35/45. OEM

Build data

Plant, GVWR class, engine and body data for any 17-character VIN.

Recalls

Check open recall campaigns against a specific vehicle by VIN.

Vehicles with shared specs

Find every vehicle that shares this one's battery, bulbs, oil capacity, platform or parts.

Group 35 battery Vehicles taking 5.0 qt Engine oil filter 1520865F0E Engine air filter 16546V0100 Spark plug 224015M015 Front wiper blades 288901CA1A

Reference guides

Cross-vehicle references for the kinds of data on this page.

Vehicle recalls & TSBs OBD-II trouble codes Torque specifications Maintenance schedules Fluid capacities & specs

Frequently asked

How much oil does the 2003 FX35/45 take?

5.0 qt of 5W-30 API SL, per the factory manual.

Does the 2003 FX35/45 have open recalls?

NHTSA lists 10 recall campaign(s) for this model year. Check your specific vehicle by VIN.

What gas mileage does the FX35/45 get?

EPA figures are 15 city / 22 highway / 17 combined mpg.