2004 FORD E-350

Typical onset: 60,000-150,000 mi

Symptoms: Sudden loss of power and loud hissing or popping from engine bay, Check engine light with misfire codes (P0301-P0310), Metal spark plug threads found on plug during removal, Rough idle and reduced power under load

Fix: The 2V Triton heads have inadequate spark plug thread engagement—only 4 threads versus 8+ on most engines. Plugs blow out, stripping the aluminum threads. Requires HeliCoil or TimeSert thread insert kit (proper fix), or in severe cases, cylinder head removal and machining. DIY with insert kit: 3-4 hours for one cylinder. Shop repair with head off: 8-12 hours labor plus machine work. Some shops pre-emptively install inserts on all cylinders during any head work.

Estimated cost: $800-1,200 per cylinder with insert kit; $3,000-5,000 if head removal required

Typical onset: 80,000-140,000 mi

Symptoms: Transmission slipping, delayed engagement, or no movement, Milky or strawberry-colored transmission fluid (coolant mixing), Engine overheating or coolant loss with no external leaks, Gray or foamy engine coolant in reservoir

Fix: The factory transmission cooler inside the radiator develops internal leaks, allowing coolant into the trans and vice versa. Coolant destroys clutch packs and torque converter within days. Requires new radiator, transmission flush (or rebuild if contamination went far), external cooler install recommended. If caught early (milky fluid, no slip): flush, radiator, cooler. If delayed: full transmission rebuild. Labor: 6-8 hours for cooler/radiator/flush; 18-24 hours for rebuild.

Estimated cost: $1,200-2,000 if caught early; $3,500-5,500 with transmission rebuild

Typical onset: 70,000-120,000 mi

Symptoms: Loud ticking or tapping noise from engine bay, especially on cold start, Exhaust smell in cabin or under hood, Visible soot streaks on manifold or head, Check engine light with O2 sensor codes (P0151, P0171, etc.)

Fix: Studs corrode and snap, or threads strip from the aluminum head. Manifolds warp from heat cycles. Requires manifold removal, broken stud extraction (often requires drilling and EZ-outs), retapping threads, new studs/bolts, and new manifolds or resurfacing. Both sides often done together. 8-12 hours labor for both sides with stud extraction.

Estimated cost: $1,800-3,200 for both sides with new manifolds

Symptoms: No start or stalling, especially when fuel tank is 1/4 to 1/2 full, Intermittent stalling that gets worse over time, Engine cranks but won't fire, or starts then dies immediately, No fuel pump prime sound when key turned to 'on'

Fix: The FPDM (mounted on the frame rail near the fuel tank) overheats and fails, cutting power to the fuel pump. Common Ford issue across platforms. Replacement is straightforward: 1-1.5 hours labor. Part is $150-250. Some techs add heat shielding or relocate to cooler spot as preventive.

Estimated cost: $300-500

Typical onset: 90,000-150,000 mi

Symptoms: Coolant seepage at front or rear of intake manifold, Slow coolant loss with no visible external puddles, Sweet smell from engine bay, White residue or crusty buildup on intake valley

Fix: Composite intake gaskets deteriorate from heat cycles. Requires intake removal, gasket set, and coolant flush. On V10, it's a big job due to manifold size and coil-pack removal. 6-8 hours labor. Good time to do spark plugs and coil boots while in there.

Estimated cost: $1,200-1,800

Typical onset: 80,000-130,000 mi

Symptoms: Gear oil dripping from front of differential or on driveshaft, Oil spots under center of vehicle when parked, Whining noise from rear axle under load (if fluid level drops significantly)

Fix: Pinion seal hardens and leaks. Requires driveshaft removal, pinion nut torque spec verification (critical for bearing preload), seal replacement, fluid refill. 2-3 hours labor. If bearing preload was lost, may need full pinion bearing setup (longer job). Most common on high-mileage work vans.

Estimated cost: $400-700