Toyota Highlander
3.0L V6 from the early 2000s. The oil sludge problem on 1997-2002 models is notorious — PCV valve design + narrow cooling passages with neglected oil changes. Toyota issued a repair program. From 2003 with revised PCV, no longer a systematic issue. Rear valve cover gasket likes to leak — poor access.
Highlander XU20 V6 — family SUV with sludge history
220 hp V6 in the first Highlander. Oil sludge on 2001-2003 is THE topic — check oil change records. Engine fundamentally robust when maintained. Camry-based platform: drives like a car, not a truck.
Engine Weaknesses 3
PCV valve design + narrow cooling passages cause sludge buildup with neglected oil changes. Toyota issued repair program. Especially 1997-2002.
Symptoms: Thick black oil, oil pressure loss, engine noise, check engine light
Head gaskets can fail past 200k km. Rather rare risk on well-maintained engines.
Symptoms: Overheating, coolant loss, white smoke
Rear valve cover gasket with poor access. Oil drips onto exhaust — smell and smoke.
Symptoms: Oil smell, slight smoke from engine bay
Vehicle Weaknesses 1
Same 1MZ-FE issue as the Camry XV30. Toyota repair program expired. Check oil change history when buying.
Reports & Tests
1644 owner complaints filed with NHTSA (2001–2007). Most reported: Brakes (248), Visibility (240), Cruise Control (215).