6.6L Duramax Maintenance Schedule

Service Intervals, Part Numbers, & Fluid Capacities for all 6.6L Duramax Engines

When purchasing parts for your Duramax, be cautious with model years where a new engine was phased in/out as the incoming engine may have parts that are not interchangeable with the outgoing engine. You can use our VIN ID table to verify the engine that your truck is equipped with (see footnote at bottom of page). Always follow the severe duty maintenance schedule if you're driving conditions include:

• Idling for excessive periods
• Frequently traveling on short trips or under conditions that require frequent engine on/off cycles without reaching full operating temperature
• Driving off-road (or frequent 4 wheel drive use)
• Frequent towing/hauling
• Driving in extremely cold or hot environments

Service Intervals

Replace engine oil & oil filter

10,000 miles or when "change engine oil" message is displayed by the oil life monitoring system

Replace fuel filter

2003 - 2010

15,000 miles

2011 - 2016

22,500 miles or when "change fuel filter" message is displayed

Replace engine air filter

Check filter condition every oil change and replace as necessary; replace at 45,000 miles regardless

Flush engine cooling system

150,000 miles

Replace automatic transmission fluid & filters

2001 - 2011

50,000 miles (normal conditions)
25,000 miles (severe duty conditions)

2012 - 2016

Replace external filter at 45,000 mile intervals and full service at 97,500 miles under normal conditions
Perform full service (new fluid, ext & int filter) every 45,000 miles under severe duty conditions

Replace manual transmission fluid

GM advises that the ZF S6-650 6 spd manual transmission does not require service. To maintain shift quality and promote transmission life, recommend replacing fluid at 60,000 mile intervals, especially if usage meets any of the severe duty conditions.

Replace transfer case fluid

2001 - 2011

50,000 miles

2012 - 2016

97,500 miles (normal conditions)
22,500 miles (severe duty conditions)

Replace front differential fluid (4x4)

Service interval not provided by GM, routine service may promote longevity. Fluid level should be checked periodically.

Replace rear differential fluid

Service interval not provided by GM, routine service may promote longevity. Fluid level should be checked periodically.

Service Part Numbers

Part numbers based on Silverado/Sierra trucks - some parts may not be compatible with Sierra/Express vans

Engine air filter

2001 - 2005

ACDelco A1618C

2006 - 2010

ACDelco A3087C

2011 - 2016

ACDelco A3141C

Engine oil filter

ACDelco PF2232

Fuel filter

ACDelco TP3018

Glow plug[1]

2001 - 2004 LBZ
(VIN 1 only, NOT 2004 LLY)

ACDelco 62G

2004 - 2005 LLY
(VIN 2 only, NOT 2006 LLY)

ACDelco 63G

2006 - 2016
(all engines)

ACDelco 9G (replaces ACDelco 61G)

Thermostat[2]

2001 - 2014

ACDelco 12T100D (front), ACDelco 12T99D (rear, alternative p/n 131131)

2015 - 2016

ACDelco 131-131

Coolant reservoir cap

2001 - 2010

ACDelco RC85

2011 - 2016

ACDelco RC115

Camshaft position sensor (CPS)

2001 - 2004
(LBZ, VIN 1)

GM 2134274 (alternatively 2132485)

2004.5 - 2015
(2004 LLY only, VIN 2)

GM 97365038

2016

GM 1267264

Crankshaft position sensor (CKP)

2001 - 2004
(LBZ, VIN 1)

GM 2134277 (alternatively 2132486)

2004.5 - 2015
(2004 LLY only, VIN 2)

GM 9765037

2016

GM 12672641

Automatic transmission filter

External filter, 2001 - 2016

ACDelco TF950

Internal filter, 2001 - 2005

GM 29537965 (5 speed Allison)

Internal filter, 2006 - 2010

ACDelco TF920

Internal filter, 2011 - 2016

GM 29542833

Fluid Specs

Engine oil

15W-40

Preferred viscosity, ambient temp > 0° F

5W-40

Preferred viscosity, ambient temp < 0° F, acceptable in all temps

10W-30

Listed as acceptable for certain model years - not advised

Engine coolant

50/50 DEX-COOL engine coolant, distilled water

Automatic transmission fluid

2001 - 2005 (5 spd)

DEXRON-III automatic transmission fluid (ATF)

2006 - 2016 (6 spd)

DEXRON-IV automatic transmission fluid (ATF)

Manual transmission fluid

GM TranSynd full synthetic transmission fluid (GM 12378515, ZF S6-650 6 spd transmission)

Transfer case fluid

2003-2007 manual shift

DEXRON-III automatic transmission fluid (ATF)

2003 - 2007 auto shift

AUTO-TRAK II (GM 12378508)

2008 - 2016

DEXRON-IV automatic transmission fluid (ATF)

Front differential fluid

2003 - 2010

SAE 80W-90 synthetic axle lubricant (gear oil)

2011 - 2016

SAE 75W-90 synthetic axle lubricant (gear oil)

Rear differential fluid

SAE 75W-90 synthetic axle lubricant (gear oil)

Oil & Fluid Capacities

Capacities used for reference only - always fill to proper dipstick or fill plug level

Engine oil capacity

10 quarts w/ filter

Engine Cooling system capacity

22.0 - 28.5 quarts (5.5 - 7.125 gallons), varies based on model year and optional equipment

Automatic transmission fluid refill

7.4 quarts nominal refill capacity when transmission is dropped and internal filter is replaced

Manual transmission fluid capacity

5.8 quarts (ZF S6-650 6 spd)

Transfer case fluid capacity

2001 - 2007

2.0 quarts

2008 - 2016

1.6 quarts

DEF tank capacity

5.3 gallons

[1]Model years with engine crossovers should have engine model verified by VIN number before ordering glow plugs. Glow plugs are not interchangeable with all model years. See: Duramax engine models by VIN number
[2] 2001 to 2014 model year engines use a dual thermostat system, 1 front and 1 rear mounted thermostat.