2003 Isuzu Ascender 2WD

Factory specifications, fluid capacities, torque values, EPA fuel economy and the federal safety record for the 2003 Ascender 2WD.

Quick specs

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

Lug nut torque100 ft-lbsOEM · verified

Fitment & sizes

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

From the factory this vehicle uses a BCI 78 · 600 CCA battery, OE oil filter 8889842150. 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 78 · 600 CCAOEM · verified

Tire sizeP245-65R17OEM · verified

Wheel / rim7-J inOEM · verified

OE service part numbers OEM · verified

Engine oil filter	8889842150 alt 8890173420
Engine air filter	8192397130
Fuel filter	8889830680
Spark plug	2901230720 alt 8126816630
Front wiper blades	8152143460
Thermostat	8125611550 alt 8125712610

Full specifications

Engine, drivetrain, dimensions and economy.

Dimensions & weight NHTSA vPIC

Overall length	207.5 in
Overall width	74.8 in
Overall height	77.2 in
Wheelbase	129.1 in
Curb weight	4837 lb
Track (front / rear)	62.2 / 62.2 in
Weight distribution (front / rear)	54/46

Service quick specs OEM factory data

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

This engine SYNTHETIC · 75W-90 · GL-5 in the differential. Torque lug nuts to 100 ft-lbs, the oil drain plug to 18.0 ft-lbs. The firing order is 1-5-3-6-2-4. 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

Differential Gear Oil	SYNTHETIC · 75W-90 · GL-5
Differential Gear Oil Capacity	4.3 Pints
Engine Coolant	DEX-COOL OR EQUIVALENT
Power Steering Fluid	GM PART NO. 89021184 OR EQUIVALENT
Transfer Case Fluid	GM PART NO. 12378508
Transfer Case Fluid Capacity	3.8 Pints

Engine torques

Camshaft Bearing/Carrier Cap Bolts or Studs	9 ft-lbs
Intake Manifold to Engine Bolts	7.4 ft-lbs
Intake Manifold to Engine Bolts	7.4 ft-lbs
Engine Oil Pan Drain Plug	19.0 ft-lbs
Engine Oil Pan Drain Plug	18.0 ft-lbs
Oil Pump to Cylinder BLock Bolts/Studs	7 ft-lbs

Chassis torques

Lug Nuts	100 ft-lbs
Front Wheel Hub	103 ft-lbs

Ignition

Cylinder Firing Order	1-5-3-6-2-4
Spark Plug Gap	0.040 in
Spark Plug Torque	13.0 ft-lbs

Battery & A/C

Refrigerant	R134a
Oil Group	PAG
Oil Type	46
Oil Capacity	5.00 oz
Standard BCI Group Number	78
Standard BCI Cranking Performance	600 cca
Standard BCI Group Number	78
Standard BCI Cranking Performance	600 cca

Service checks

Pressure Test	15 psi
Radiator Cap Pressure Relief	15 psi
Thermostat Opening Temperature	188-206 °F
Pressure Test	15 psi
Radiator Cap Pressure Relief	15 psi
Thermostat Opening Temperature	188-206 °F
Fuel Pump Pressure Minimum	50.0 psi
Fuel Pump Pressure Maximum	57.0 psi

Brakes

Torque Caliper to Bracket	85 ft-lbs / 23 ft-lbs
Torque to Knuckle	133 ft-lbs / 89 ft-lbs
Minimum Pad Thickness	0.039 in
Minimum Shoe Thickness	0.039 in
Rotor Max Parallel Variation	0.0001 in
Rotor Runout Limit	0.002 in
Rotor Nominal Thickness From	1.142 in / 0.787 in
Rotor Nominal Thickness To	1.142 in / 0.787 in

Multi-step torque procedures OEM · verified

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

18 ft. lbs., Step 2: 110

18 ft. lbs

Cylinder Head — tightening sequence 5 stages

1	M11 bolts	22 ft. lbs
2	M11 bolts	90 degrees
3	M11 bolts 1-8	90 degrees
4	M11 bolts 9 and 10	50 degrees
5	22

Engine Flywheel Bolts — tightening sequence 1 stages

18 ft. lbs., Step 2: 50

18 ft. lbs

Exhaust Manifold to Cylinder Head Bolts — tightening sequence 1 stages

15 ft. lbs, Step 2: 15 ft. lbs., Step 3: 15

15 ft. lbs

Exhaust Manifold to Cylinder Head Bolts — tightening sequence 1 stages

11 ft. lbs., step 2: 18

11 ft. lbs

Intake Manifold to Engine Bolts — tightening sequence 1 stages

3.7 ft. lbs., step 2: 7.4

3.7 ft. lbs

Exhaust Manifold to Cylinder Head Bolts — tightening sequence 1 stages

11 ft. lbs., step 2: 18

11 ft. lbs

Main Bearings — tightening sequence 1 stages

18 ft. lbs., Step 2: 180

18 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 7,500 mi; spark plugs every 100,000 mi; coolant at 150,000 mi. The big-interval services (at 150,000 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 7,500 mi	CV Joint Boot (inspect) · Drive Axle Assembly (drain & refill) · Driveshaft (inspect) · Engine Oil Filter (replace) · Tire & Wheel Assembly (rotate)
Every 30,000 mi	Engine Air Filter Element (replace) · Fuel Filter (replace)
Every 50,000 mi	Transfer Case Assembly (drain & refill)
Every 100,000 mi	Spark Plugs (replace) · Transmission Fluid & Filter (replace)
At 150,000 mi	Engine Coolant System (drain, flush & refill) · Engine Coolant System Hoses (inspect) · Radiator Cap (inspect)