HUMMER›H2›2004›H2/hummer/h2/2004/h2/

2004 HUMMER H2 — H2

Factory specifications, fluid capacities, torque values, EPA fuel economy and the federal safety record for the 2004 H2 H2.

Engine H2

The 2004 HUMMER H2 is built around an H2 engine requiring 6 qt of 10W-30 API oil, establishing the mechanical baseline for this model year. Across the 2002-2006 model years, this specific year logged 59 total owner complaints, positioning it well above the 2002 low of 2 but significantly below the 2003 peak of 141. With 4 recalls issued and visibility identified as the top complaint area, the 2004 model represents a middle ground in the model's reliability history rather than an outlier.

Model year2009 2008 2007 2006 2005 2004 2003

Quick specs

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

Engine oil capacity6 qtOEM · verified

Engine oil type10W-30 APIOEM · verified

Lug nut torque140 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 79 · 840 CCA battery, OE oil filter 12731172. Note the factory fuel filter is now discontinued — plan on a superseded or quality aftermarket equivalent, which the part pages below list where known.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 79 · 840 CCAOEM · verified

OE service part numbers OEM · verified

Engine oil filter	12731172
Engine air filter	15286805
Fuel filter	19368932 discontinued
Battery	88864064
Front wiper blades	15060730
Serpentine belt	12576447 alt 12637204
Thermostat	12600171 alt 12570307
Cabin air filter	88986533

Full specifications

Engine, drivetrain, dimensions and economy.

Dimensions & weight NHTSA vPIC

Overall length	187.4 in
Overall width	81.1 in
Overall height	79.1 in
Wheelbase	122.8 in
Curb weight	6398 lb
Track (front / rear)	68.9 / 69.7 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 holds 6 qt of 10W-30 API engine oil, SYNTHETIC · 75W-90 · GL-5 in the differential. Torque lug nuts to 140 ft-lbs, the oil drain plug to 18.0 ft-lbs. The firing order is 1-8-7-2-6-5-4-3. 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

Automatic Transmission Fluid	ATF
Automatic Transmission Fluid Capacity	7.4
Differential Gear Oil	SYNTHETIC · 75W-90 · GL-5
Differential Gear Oil Capacity	5.5 qt
Engine Oil	10W-30 · API
Engine Oil Capacity	6 qt
Power Steering Fluid	USE GM PART NO. 1052884 OR EQUIVALENT

Engine torques

Engine Oil Pan Drain Plug

18.0 ft-lbs

Chassis torques

Lug Nuts	140 ft-lbs
Transfer Case Fill Plug	18.0 ft-lbs
Transfer Case Drain Plug	18.0 ft-lbs

Ignition

Cylinder Firing Order	1-3-5-4-2
Cylinder Firing Order	1-8-7-2-6-5-4-3
Spark Plug Manufacturer	AC Delco
Spark Plug Gap	0.060 in
Spark Plug Torque	11 ft-lbs
Spark Plug Manufacturer	AC Delco
Spark Plug Type	41-985
Spark Plug Gap	0.040 in

Battery & A/C

Refrigerant	R134a
Oil Group	PAG
Oil Type	46
Standard BCI Group Number	79
Standard BCI Cranking Performance	840 cca

Service checks

Pressure Test	15 psi
Radiator Cap Pressure Relief	15 psi
Thermostat Opening Temperature	188-206 °F
Engine Compression	100
Engine Compression	100 Minimum psi
Engine Oil Pressure	6
Intake Valve Lash	Hydraulic in
Exhaust Valve Lash	Hydraulic in

Brakes

Torque Caliper to Bracket	80 ft-lbs
Torque to Knuckle	221 ft-lbs / 122 ft-lbs
Minimum Pad Thickness	Front: 0.030; Rear: 0.030 in
Rotor Max Parallel Variation	0.001 in
Rotor Runout Limit	0.005 in
Rotor Nominal Thickness From	1.496 in / 1.142 in
Rotor Nominal Thickness To	1.496 in / 1.142 in
Rotor Minimum Machining	1.457 in / 1.102 in

Multi-step torque procedures OEM · verified

Cylinder Head — tightening sequence 4 stages

Prep Do not reuse old bolts. Use new bolts coated with clean engine oil. · M11 Bolts 1-10:

1	22.0 ft. lbs.	22 ft. lbs
2	90 degrees	90 degrees
3	Bolts 1-8	90 degrees
4	Bolts 9and10	50 degrees
1	22.0 ft. lbs.	22 ft. lbs

Intake Manifold to Engine Bolts — tightening sequence 1 stages

7.4

Exhaust Manifold to Cylinder Head Bolts — tightening sequence 1 stages

18.0

Factory maintenance schedule OEM · verified

Normal service, condensed from the factory interval matrix.

Under the factory schedule, replace the 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	Differential (inspect fluid level) · Tire & Wheel Assembly (rotate)
Every 25,000 mi	Fuel System (inspect)
Every 50,000 mi	Transfer Case Assembly (drain & refill)
Every 100,000 mi	Engine Air Filter Element (replace) · PCV Valve (inspect) · Spark Plug Wires (inspect) · Spark Plugs (replace) · Transmission Fluid & Filter (replace)
At 150,000 mi	Accessory Drive Belt (inspect) · Engine Coolant System (drain, flush & refill)

Reliability & federal safety record

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

The 2004 HUMMER H2 sits in a notable transition within its generation, reflecting a peak in technical service bulletins (TSBs) at 748—slightly higher than both 2003 (638) and 2005 (735)—while complaints dropped significantly from 2003’s 141 to 59. Recalls remained steady at four, matching 2003 but exceeding 2005’s three, while investigations held at two, consistent with the prior and following years. The data shows 2003 as an outlier for complaints, likely due to early-build issues, whereas 2004’s decline suggests refinements were made, though visibility, electrical, and brake-related concerns persisted as top complaint areas. Crash complaints (6) and a single fire complaint align with the broader trend of moderate safety-related reports for this model year. While 2004 avoids the extreme complaint volume of 2003, the high TSB count indicates ongoing reliability adjustments, making it a *marginally* better choice than its predecessor but not definitively the strongest year in the generation. Proceed with caution, prioritizing a thorough pre-purchase inspection.

Open recalls

NHTSA campaigns

748

Service bulletins

Manufacturer communications

ODI investigations

Office of Defects Investigation

Owner complaints

6 involved a crash · 1 a fire

Owner complaints by model year NHTSA · this generation & adjacent

’02 ’03’04’05 ’06

Owner complaints filed with NHTSA, by component

All 59 complaints on record, top 8 components.

Visibility10

Electrical System8

Service Brakes7

Service Brakes, Hydraulic3

Suspension2

Power Train2

Air Bags2

Visibility/Wiper2

Source: NHTSA Office of Defects Investigation complaint database.

Recalls NHTSA · verified

Showing 2 of 4 campaigns on record for this vehicle.

05V043000Service Brakes, HydraulicReported 08/02/2005

CERTAIN TRUCKS, SPORT UTILITY VEHICLES, AND VANS EQUIPPED WITH BOSCH HYDRO-BOOST BRAKE ASSEMBLIES, THE HYDRAULIC BRAKE BOOSTER PRESSURE ACCUMULATOR MAY CRACK AND SEPARATE FROM THE HYDRO-BOOST ASSEMBLY DURING NORMAL… Remedy: DEALERS WILL TEST THE HYDRO-BOOST ASSEMBLY FOR FUNCTIONAL OPERATION OF THE TWO-FUNCTION VALVE. IF THE HYDRO-BOOST ASSEMBLY FAILS THE TEST, DEALERS WILL REPLACE THE ASSEMBLY FREE…

05V163000Seat Belts:Rear/OtherReported 22/04/2005

ON CERTAIN CREW CAB PICKUP TRUCKS AND SPORT UTILITY VEHICLES, THE 2ND ROW CENTER OCCUPANT SEAT BELT ROUTING MAY MAKE IT DIFFICULT TO POSITION THE LAP PORTION OF THE SAFETY BELT LOW AROUND THE HIPS OF OCCUPANTS… Remedy: DEALERS WILL CUT OPEN THE GUIDE LOOP, REMOVE A PORTION OF THE LOOP, AND THEN THE REMAINING TWO SIDES SHOULD BE FOLDED OVER AND SECURED WITH A RETAINER FREE OF CHARGE. THE RECALL…

Technical service bulletins NHTSA · verified

Showing 5 of 748 bulletins on record with NHTSA.

Bulletin	Date	Component	Summary
PIP5601C	2025-07-18	Unknown Or Other	This PI communicates the requirement to provide a pico file to receive diagnostic…
PIP5358D	2025-02-19	Unknown Or Other	This Preliminary Information communication provides information to the technician about…
03-06-01-023I	2024-12-17	Engine	This service bulletin explains how to measure for oil consumption and possible reasons…
PIP4723J	2024-10-25	Electrical System	This Preliminary Information communicates to the dealer the process for downloading or…
03-06-01-023H	2024-10-07	Engine	This service bulletin explains how to measure for oil consumption and possible reasons…

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 H2. 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 79 battery Vehicles taking 6 qt Engine oil filter 12731172 Engine air filter 15286805 Fuel filter 19368932 Battery 88864064

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 2004 H2 H2 take?

6 qt of 10W-30 API, per the factory manual.

Does the 2004 H2 have open recalls?

NHTSA lists 4 recall campaign(s) for this model year. Check your specific vehicle by VIN.