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Recipe - Ford 6.4L Power Stroke Diesel

Specific Fix build

Reliability tier: aggregated - verify before ordering, see /disclosure/

Emissions-side repair (modes EGR cooler failure -> #8 hydrolock / DPF clogging / regeneration problems): the 6.4 has TWO EGR coolers (primary 9P456-C and secondary 9F464-F) - both are suspects in coolant-loss/hydrolock, and the hydrolock path feeds cylinder #8 at shutdown. The early-generation DPF clogs with soot AND oil-ash (turbo seals + ring wear feed it) - clean before replacing, and fix the oil-feed root cause or the new DPF ashes up too.

Parts

• 6.4L Power Stroke EGR Cooler (OEM) - primary EGR cooler (8C3Z-9P456-C) - coolant-loss suspect #1 (qty 1)
• 6.4L Power Stroke EGR Cooler, second unit (OEM) - secondary EGR cooler (8C3Z-9F464-F) - the 6.4's second cooler, replace as a pair (qty 1)
• 6.4L Power Stroke DPF Pressure Sensor (OEM) - differential-pressure sensor - verify the DPF diagnosis before spending on the assembly (qty 1)
• 6.4L Power Stroke 6.4L DPF Cleaning Service (editorial) - professional DPF cleaning first: soot+ash bake-out at a fraction of a new assembly (qty 1)
• 6.4L Power Stroke Diesel Particulate Filter (OEM) - new DPF assembly (9C3Z-5H221-A) when the substrate is melted/oil-soaked beyond cleaning (qty 1)
• 6.4L Power Stroke Compound Turbocharger, Ford reman - if oil-through-turbo is feeding the ash load, the compound turbo seals are the root cause (qty 1)

Install order

1. confirm the DPF story with the DPS sensor before any assembly spend
2. EGR side: pressure-test; replace the leaking cooler - plan BOTH coolers, they age together
3. DPF: cleaning service first; new assembly only for melted/oil-soaked substrate
4. chase the oil source if ash-loading is heavy: turbo seals before ring wear
5. refill with the correct coolant chemistry and bleed; full regen and verify DPS readings

Expected outcome

No coolant loss, no #8 hydrolock risk, DPS behavior back to spec, regens complete.

Do not

• do not replace the DPF without checking what fed the ash - oil through worn turbo seals restarts the clock immediately

Parts budget

About $1,400-$2,650 in parts. It depends on what the diagnosis finds; each option below is what you buy together. Prices marked "at Dave's" are Dave's Auto Center's, the same as in his store; the others are approximate prices from OEM and maker catalogs, rounded (a manufacturer's list price can run higher). Parts only, no labor.

• about $1,400: 6.4L Power Stroke EGR Cooler (OEM) (about $610) + 6.4L Power Stroke EGR Cooler, second unit (OEM) (about $750)
• about $1,750: 6.4L Power Stroke Diesel Particulate Filter (OEM) (about $1,750)
• about $2,650: 6.4L Power Stroke Compound Turbocharger, Ford reman (about $2,650)

DIY or shop: Shop: two-cooler EGR work and aftertreatment handling.