7.3 Power Stroke Maintenance Guide

7.3 Power Stroke Maintenance Schedule

The maintenance schedule for "normal" driving conditions assumes the vehicle is driven unladen in ideal traffic conditions with minimal engine idling and constant road speeds. A vehicle will fall under the "severe" or "heavy duty" service category if it meets any of the following criteria:

• Vehicle is idled frequently and/or excessively (generally defined as 10 minutes or more idling within a 1 hour window)
• Vehicle makes frequent short trips in which the engine often shutdown before reaching full operating temperature
• Vehicle is driven off-road or in conditions that require the 4 wheel drive to be engaged
• Vehicle experiences light towing/hauling in excess of 1,000 miles between oil change intervals
• Vehicle tows and/or hauls medium to heavy loads
• Engine is run on biodiesel or biodiesel blends (any concentration)

As a general rule-of-thumb, most owners of a heavy duty pickup truck or van will fall under the severe/heavy duty service category, requiring an alternative maintenance schedule calling for more frequent service procedures. If in doubt about which service category your vehicle falls under, always adhere to the more stringent severe/heavy duty service intervals.

Many service intervals are provided in distance driven OR a period of time; service should be performed when either of these two conditions are met, whichever comes first.

Normal Service Intervals

[1] - Replace fluid as soon as possible anytime the unit is submerged in water; water intrusion highly likely.

Severe/Heavy Duty Service Intervals

[2] - Replace fluid as soon as possible anytime the unit is submerged in water; water intrusion highly likely.

7.3 Power Stroke Oils, Lubricants, & Fluids

Engine Oil Viscosity Chart

An engine oil viscosity grade should be selected based on the expected ambient temperature range in which the vehicle is to be operated. The 7.3L Power Stroke requires an engine oil that meets, at minimum, API CG-4/SH specifications. Note that certain viscosity grades are "acceptable" within a temperature range while others are "preferred". When possible, select an engine oil viscosity that is "preferred" within the expected temperature range. SAE 15W-40 is the most commonly used, readily available viscosity grade for the 7.3L Power Stroke.

We highly recommend a high quality synthetic motor oil due to its resilience against degradation and oxidation in engines employing an HEUI injection system. Synthetic motor oils will provide improved wear protection under the strenuous oil pressures these systems operate at.

Oil & Fluid Specifications

[3] - Refer to viscosity chart for complete viscosity grade application details; be mindful of the terms "preferred" and "acceptable". When possible, select a viscosity grade that is preferred within the expected ambient temperature range in which the vehicle is being operated.
[4] - 50/50 coolant-to-water ratio is ideal under most circumstances and provides protection against freezing down to -34° F. The ratio can be increased to 60% engine coolant, 40% water in extremely cold environments, as necessary. Do not exceed a 60/40 ratio.
[5] - MERCON V replaces original, now defunct MERCON specification in all transmission applications
[6] - MERCON LV replaces prior Motorcraft XL-12 transfer case fluid specification; MERCON V is not suitable for use in transfer cases
[7] - Limited slip differentials may require a friction modifier to prevent chatter; use Motorcraft XL-3

Oil & Fluid Capacities

[8] - Refill capacity with filter change; some repair procedures may require additional oil to be added if the high pressure oil pump reservoir, hoses, or cylinder head oil rails are drained. Always verify correct engine oil level with vehicle parked on level ground.
[9] - Transmission fluid should be filled until the level has reached the appropriate dipstick indicator
[10] - Fill component until oil has reached the lower level of the fill plug hole; fill plug height is the appropriate lubricant level indicator. When checking fluid level, oil should be no less than 1/4 inch below the fill plug opening. Always fill and check fluid level with vehicle parked on level ground.
[11] - If friction modifier/additive is required for limited slip differential, add before filling with gear oil

7.3 Power Stroke Service Parts List