Service intervals for Hummer H2 Petrol 6.2 V8, 8 cylinders, 393 hp

Hummer H2 Petrol 6.2 V8 (393 hp): Factory Service Intervals

This guide covers the Hummer H2 petrol 6.2-litre V8 with eight cylinders and 393 hp, used in the later H2 range. It must not be serviced using a generic fixed 10,000 km or 15,000 km interval: GM uses an Engine Oil Life System and alternating Maintenance I / Maintenance II services.

The 6.2 V8 is a separate powertrain from the earlier 6.0 V8 H2. It has a six-speed automatic transmission, VIN engine code 8, and different fluid specifications. Use the owner manual for the exact model year and VIN as the controlling source.

Basic technical information

The factory maintenance schedule uses these mileages: 25,000 mi / 40,000 km; 50,000 mi / 80,000 km; 75,000 mi / 120,000 km; 100,000 mi / 160,000 km; 125,000 mi / 200,000 km; and 150,000 mi / 240,000 km. 2008 Hummer H2 Owner Manual

Main service intervals

The mileage-based items below are performed at the first Maintenance I or Maintenance II service after the stated mileage.

Engine oil and filter

The H2 uses a computer-controlled Engine Oil Life System. GM states that it calculates oil life from engine revolutions and engine temperature, not from mileage alone. When CHANGE ENGINE OIL SOON appears, change the engine oil and filter within the next 600 miles / 1,000 km.

Even if the message does not appear, the oil and filter must be changed at least once every 12 months. Reset the Oil Life System after every oil change. If it is reset accidentally, GM requires the vehicle to be serviced within 3,000 miles / 5,000 km of the previous service. 2008 Hummer H2 Owner Manual

The original manual specifies SAE 5W-30 oil meeting the then-current GM6094M standard. This is a historical specification, so any currently available oil should be verified against the vehicle’s VIN-specific documentation and the lubricant maker’s current approvals. The quoted 5.7-litre capacity is approximate; GM instructs owners to confirm the final level on the dipstick after refilling.

Maintenance I and Maintenance II

GM alternates Maintenance I and Maintenance II when an oil-service message appears.

• Maintenance I applies when the oil message appears within 10 months of vehicle purchase or the last Maintenance II.
• Maintenance II applies if the previous service was Maintenance I.
• Maintenance II is always required if the message appears 10 months or more after the previous service, or if no oil message has appeared for one year.

Both Maintenance I and Maintenance II include:

• Engine oil and filter replacement, followed by an Oil Life System reset.
• Lubrication of specified chassis components.
• A visual check for leaks or damage.
• Air-filter inspection in dusty or dirty operating conditions.
• Tyre rotation, pressure and wear checks.
• Brake-system inspection.
• Engine-coolant and windscreen-washer-fluid checks.
• Any additional mileage-based work that has become due.

Maintenance II additionally includes inspections of the steering, suspension, cooling system, wiper blades and restraint systems; lubrication of body components; and an automatic-transmission fluid-level check. 2008 Hummer H2 Owner Manual

Engine air filter and fuel system

The factory air-filter procedure depends on whether the H2 has an air-filter restriction indicator.

The manual also requires replacement of the engine air filter at the first scheduled service after 100,000 miles. In dusty or dirty conditions, inspection is required during both Maintenance I and Maintenance II services. 2008 Hummer H2 Owner Manual

The published schedule calls for inspection of the fuel system and exhaust system every 25,000 miles through 150,000 miles. It does not list a scheduled fuel-filter replacement interval. A generic fuel-filter interval from an earlier H2 6.0 V8 must not be copied to this 6.2 V8 schedule.

Spark plugs and ignition wires

The 6.2 V8 has eight spark plugs. GM specifies replacement at 100,000 miles / 160,000 km and inspection of the spark-plug wires at the same service. The factory spark-plug gap is 0.040 in / 1.01 mm. 2008 Hummer H2 Owner Manual

Automatic transmission, transfer case and axles

The 6.2 V8 H2 uses a six-speed automatic transmission. The owner manual specifies DEXRON-VI automatic-transmission fluid for both the transmission and transfer case.

For normal use, change the automatic-transmission fluid and filter at 100,000 miles / 160,000 km. For severe use, the interval is 50,000 miles / 80,000 km, then 100,000 and 150,000 miles.

GM defines severe transmission service as one or more of the following:

• Mainly heavy city traffic when the outside temperature regularly reaches 32°C or above.
• Driving in hilly or mountainous terrain.
• Frequent trailer towing.
• Taxi, police or delivery-service use.

Transfer-case fluid is scheduled at 50,000, 100,000 and 150,000 miles. The manual also requires the transfer-case vent hose to be checked for kinks and correct installation. 2008 Hummer H2 Owner Manual

For the front and rear axles, GM does not prescribe a regular fluid-check or fluid-change interval in the maintenance table. The owner manual says to inspect the axle lubricant if there is a suspected leak or unusual noise. A fluid loss indicates a fault that should be repaired, not merely topped up. 2008 Hummer H2 Owner Manual

Coolant, accessory belt and timing chain

The factory cooling system uses a 50/50 mixture of clean water and DEX-COOL coolant. GM specifies cooling-system service at 150,000 miles / 240,000 km or five years, whichever occurs first. The specified service includes draining, flushing and refilling the system; inspecting hoses; cleaning the radiator, condenser, pressure cap and filler neck; and pressure-testing the system and cap.

GM warns that if a coolant other than DEX-COOL is used, coolant service may be required at 30,000 miles / 50,000 km or 24 months, whichever comes first. 2008 Hummer H2 Owner Manual

Inspect the accessory drive belt at 150,000 miles / 240,000 km. GM specifies replacement only if the belt is frayed, excessively cracked or visibly damaged.

The 6.2 V8 uses a timing-chain drive. Neither the owner maintenance schedule nor the repair documentation lists a routine timing-chain replacement interval, so a timing-belt replacement interval must not be published for this engine. Hummer H2 6.2L service information

Brakes, tyres and owner checks

The factory program requires brake-system inspection during both Maintenance I and Maintenance II. This includes brake lines, hoses, pads, rotors, calipers and the parking brake. The master cylinder uses DOT 3 brake fluid, but the owner schedule does not specify a fixed mileage or time interval for complete brake-fluid replacement. A statement such as “replace every two years” is therefore not a factory H2 interval. 2008 Hummer H2 Owner Manual

GM also specifies the following owner checks:

The cited H2 maintenance schedule does not include a routine cabin-air-filter replacement item. Do not transfer an interval from another GM vehicle without confirming the exact vehicle equipment and VIN.

Quick service summary

Important note

For an imported or used Hummer H2, the owner manual for the exact model year and VIN remains the controlling source. Service history, frequent towing, off-road use, climate, modifications and the fluids already fitted to the vehicle can affect what work is currently due.