6.9L & 7.3L IDI Diesel Maintenance Schedule

6.9L, 7.3L IDI Service Intervals

Note - Select service intervals represent an adaptation of Ford's OEM recommendations that account for procedures not listed in the original owners manual/diesel supplement.

Operation	Interval(s)
Replace engine air filter	30,000 miles regardless of condition Check at oil change intervals, replace as necessary
Replace engine oil & oil filter	5,000 miles or 6 months under normal driving conditions 2,500 miles or 3 months under severe driving conditions
Drain fuel water separator	5,000 miles 6.9L IDI water separator located on driver side firewall 7.3L IDI water separator integrated into fuel filter assembly
Replace fuel filter	15,000 miles under normal driving conditions 7,500 miles under severe driving conditions
Check & adjust drive belt tension	15,000 miles (models with non-serpentine belt only, i.e. no belt tensioner)
Inspect crankcase depression regulator valve (CDR)	30,000 miles Suggest replacing every 60,000 miles regardless of condition
Check coolant condition	Annually test for proper SCA/DCA level under normal conditions More frequent inspection is advised under severe driving conditions
Flush & replace engine coolant	36 months regardless of mileage
Replace automatic transmission fluid & filter	30,000 miles
Replace manual transmission fluid	60,000 miles
Replace transfer case fluid	60,000 miles (more frequent service advised if 4 wheel drive used frequently) Replace immediately anytime transfer case is submerged
Replace front differential fluid (4x4)	100,000 miles under normal driving conditions 30,000 miles under severe driving conditions Replace immediately anytime differential is submerged
Replace rear differential fluid	100,000 miles under normal driving conditions 30,000 miles under severe driving conditions Replace immediately anytime differential is submerged

6.9L, 7.3L IDI Service Part Numbers

Note - All part numbers listed applicable to Ford F-Series trucks (F-250/F-350/F-Super Duty). Select part numbers may not be compatible with engines found in E-Series/Econoline vans; always verify compatibility with your parts specialist.

Part Description	Part Number(s)
Engine air filter	6.9L, 7.3L IDI, naturally aspirated	Motorcraft FA-1057 (Ford E7TZ-9601-A)
	7.3L IDI, factory turbo	Motorcraft FA-1605 (Ford F3TZ-9601-Z)
Engine oil filter	Motorcraft FL-784
Engine oil fill cap	Stant 11066 (Supersedes 10066)
Fuel filter	6.9L IDI	Motorcraft FD-811 Donaldson P550811
	7.3L IDI	Motorcraft FD-3375 Donaldson P559852 (kit w/ bowl & drain valve)
Crankcase depression regulator (CDR) valve	Ford E3TZ-6A665-A (listed as "adapter" by Ford)
CDR valve grommet/gasket	Ford E3TZ-6A892-A
Fuel Lift pump (low pressure)	Carter M60278 (mechanical lift pump, engine block mounted)
Glow plug	6.9L IDI	Motorcraft ZD1A (Ford E5TZ-12A342-B)
	7.3L IDI	Motorcraft ZD9 (Ford F2TZ-12A342-A)
Glow plug controller	6.9L IDI	Motorcraft SW5241
	7.3L IDI	Ford E7TZ-12B533-A
Glow plug relay	Motorcraft DY-861 (7.3L IDI only)
Thermostat	Motorcraft RT-1049 (Ford E5TZ-8575-C)
Thermostat housing gasket	Motorcraft RG-531 (Ford E3TZ-8255-A)
Radiator cap	Stant 10229
SCA/DCA	Motorcraft VC-8 or Fleetguard DCA4 DCA60L Use with test strips Fleetguard CC2602A to maintain SCA/DCA concentration
Engine oil cooler assembly	Ford F3TZ-6A642-C
Engine oil cooler o-rings ^[1]	Large o-ring	Ford 1C3Z-6C610-BA
	Small o-ring	Ford 1C3Z-6K649-BA
Engine oil cooler header gaskets	Ford F7TZ-6A636-AAA (front) Ford F4TZ-6A636-A (rear)
Automatic transmission filter	C6, 3 spd	Motorcraft FT-52 (Ford D5AZ-7A098-B)
	AOD, 4 spd	Motorcraft FT-58 (Ford E1AZ-7A098-A)
	2WD E4OD, 4 spd	Motorcraft FT-113 (Ford YC3P-7G186-AB)
	4WD E4OD, 4 spd	Motorcraft FT-114 (Ford YC3Z-7A098-AA)

^[1] 1983/1984 model year 6.9L diesels may have a 6 o-ring oil cooler which requires (4) small and (2) large oil cooler o-rings. Later 6.9L diesels and all 7.3L IDI diesels require (2) small and (2) large o-rings.

6.9L, 7.3L IDI Fluid Specs & Capacities

Component	Oil/Fluid Specification		Oil/Fluid Capacity ^[1]
Engine oil	Ambient temp > 0° F	SAE 15W-40 Recommend Amsoil Heavy Duty 15W-40 synthetic diesel oil ^[2]	10 quarts w/ filter
	Ambient temp < 60° F	SAE 10W-30 Recommend Amsoil Heavy Duty 10W-30 synthetic diesel oil
	Ambient temp > 30° F	SAE 30
Engine coolant	50/50 mixture of ethylene glycol engine coolant and distilled water Motorcraft green VC-5 engine coolant (concentrate) Motorcraft green VC-5DIL engine coolant (pre-mixed) Motorcraft VC-8 SCA/DCA ^[3]		7.25 - 7.75 gallons
Automatic transmission ^[4]	C6 (3 spd)	MERCON V automatic transmission fluid ^[5] Ford/Motorcraft XT5QMC MERCON V ATF	12 - 13.5 quarts
	AOD (4 spd)		12.25 quarts
	E4OD (4 spd)		13.5 quarts
Manual transmission	T-19 (4 spd)	50W engine oil or 80W-90 non-hypoid gear oil	3.5 quarts
Manual transmission	ZF S5-42 (5 spd)	MERCON V automatic transmission fluid ^[5] Ford/Motorcraft XT-5-QMC MERCON V ATF Recommend Amsoil OE synthetic ATF	3.38 quarts
Hydraulic clutch system	DOT 3 brake fluid Motorcraft PM-1-C DOT 3		N/A
Transfer case	BorgWarner BW1345	MERCON LV automatic transmission fluid ^[6] Ford/Motorcraft XT-10-QLVC MERCON LV ATF Recommend Amsoil OE fuel-efficient synthetic ATF	3.25 quarts
Transfer case	BorgWarner BW1356		2 quarts
Front differential	Dana 50 TTB (IFS)	SAE 80W-90 gear oil Recommend Amsoil Severe Gear 80W-90 synthetic gear oil	2 quarts
Front differential	Dana 60 (solid)		3 quarts
Rear differential ^[7]	Sterling 10.25	SAE 75W-140 full synthetic Recommend Amsoil Severe Gear 75W-140 synthetic gear oil	3.25 - 3.50 quarts
	Dana 80		4.2 quarts
	Dana 70	SAE 80W-90 gear oil Recommend Amsoil Severe Gear 80W-90 synthetic gear oil	3.25 - 3.7 quarts
	Dana 60		3 quarts

^[1] All oil and fluid capacities are nominal; always fill to proper dipstick, fill plug, or indicator level and verify proper oil/fluid level before operating vehicle.
^[2] For high mileage engines, consider a high TBN engine formulation such as Amsoil 15W-40 Heavy Duty TBN 12 synthetic diesel oil. The higher TBN level will counteract acids produced by blowby contamination, keeping the PH level of the engine oil balanced for a longer duration. Amsoil full synthetic diesel oils are premium products that typically reduce fuel dilution and oil consumption in aging diesel engines.
^[3] Supplemental coolant additive/diesel coolant additive (SCA/DCA) required to prevent cavitation. Use per instructions and periodically test and adjust SCA/DCA level to prevent cavitation in 7.3L IDI diesels.
^[4] Total fluid capacity listed for all automatic transmissions; service refill capacity will be much less.
^[5] MERCON V supersedes original MERCON automatic transmission fluid specification.
^[6] MERCON LV supersedes original MERCON ATF and previous XL-12 transfer case fluid specification. Do NOT use MERCON V in transfer cases. Recommend Amsoil OE fuel efficient ATF, a high performance alternative that meets or exceeds Ford MERCON LV spec for transfer cases.
^[7] Limited slip differentials may require Motorcraft XL-3 friction modifier to prevent differential chatter; use (1) 4 oz bottle.