2011 MITSUBISHI ENDEAVOR

Typical onset: 80,000-140,000 mi

Symptoms: excessive oil consumption (quart every 500-1000 miles), blue smoke on startup or acceleration, misfire codes P0300-P0306, loss of compression on one or more cylinders, rattling/knocking from lower end as bearing damage progresses

Fix: The 6G75 has weak piston ring lands that crack under heat/carbon buildup, especially if oil changes were stretched. Diagnosis requires compression/leak-down testing. Fix is either piston replacement (12-16 hours pulling heads, honing cylinders, new rings) or short block swap (18-22 hours). Many shops recommend short block or used engine due to labor overlap and risk of machining costs. If bearings are scored, full rebuild or replacement is mandatory.

Estimated cost: $4,500-7,500

Typical onset: 90,000-130,000 mi

Symptoms: transmission slipping or delayed engagement, milky/pink transmission fluid (coolant mixing), overheating transmission, Check Engine light with trans codes, coolant loss without visible leaks

Fix: The internal transmission cooler inside the radiator fails, allowing coolant into the ATF and vice versa. This destroys the F4A42 4-speed automatic within days if not caught early. Repair requires new radiator, full transmission flush (often triple-flush with solvent), all cooler lines, and frequently a reman transmission if contamination progressed. Labor is 8-12 hours for full job including trans R&R if needed. Catch it early (check fluids at every service) or budget for transmission replacement.

Estimated cost: $2,200-5,800

Typical onset: 100,000-150,000 mi

Symptoms: external coolant leaks at head/block interface, white smoke from exhaust, overheating under load, bubbles in coolant reservoir, oil/coolant cross-contamination

Fix: The V6 head gaskets fail externally (coolant weeping) or internally (combustion gases into coolant). Often discovered during diagnosis of overheating or misfire issues. Both heads must come off (14-18 hours labor), surfaces checked for warpage (machine shop adds $300-600), new gaskets, timing components, and all coolant hoses while open. If heads are warped beyond spec, add $800-1200 for resurfacing or replacement heads.

Estimated cost: $3,200-5,000

Typical onset: 70,000-110,000 mi

Symptoms: clunking when shifting from Park to Drive/Reverse, vibration at idle in gear, excessive engine movement visible from engine bay, harsh engagement into gear

Fix: The rear transmission mount (hydro-mount style) deteriorates and the fluid leaks out, leaving metal-on-metal contact. Replacement is straightforward (1.5-2.5 hours) but requires supporting the transmission/transfer case assembly. Replace both engine mounts at same time if they're original — labor overlap saves money. OEM mounts last longest; aftermarket often fail within 30k.

Estimated cost: $350-650

Typical onset: 90,000-150,000 mi

Symptoms: knocking/tapping from lower engine, worse when cold, metallic rattling that increases with RPM, low oil pressure warning, metal shavings in oil during changes, sudden catastrophic failure/seized engine

Fix: Tied to the sludge/oil consumption issue — when owners run low on oil between changes, bearings starve. Diagnosis via oil pressure test and bearing inspection through oil pan. If caught early (light scoring), bearing replacement alone is 10-14 hours. If crank journals are damaged, crank must be turned or replaced (20-26 hours, plus machine work). Most techs recommend short block or used engine at this point due to labor cost vs. remaining engine life.

Estimated cost: $3,800-6,500

Typical onset: 80,000-120,000 mi

Symptoms: hard starting after sitting, sputtering/stumbling under acceleration, stalling at idle or low speed, fuel pump whine audible from rear seat, Check Engine light with lean codes P0171/P0174

Fix: The in-tank fuel pump module includes a sock filter that clogs from sediment, especially in vehicles that sat or used low-quality fuel. Mitsubishi filter is non-serviceable; entire pump module must be replaced. Tank drop required (2.5-3.5 hours). Replace fuel filter and inspect fuel lines while tank is down. Some techs flush tank if sediment is heavy.

Estimated cost: $650-1,100