Sludge can build up in the engine because Lexus did not recommend frequent enough oil changes. Lexus will sometimes offer a discount on cleaning the engine if necessary. Owners who changed their oil every 3,000 miles did not experience these problems. This sludge build up can lead to excessive oil consumption.Google+
Car Problem Reports
Lexus GS300 Sludge Buildup on Engine Due to Infrequent Oil Changes
Lexus GS300 Problem
Engine Affected: 3.0L V6
Visitor, 1998 Lexus GS300, 3.0L V6
3,000 - 4,000 miles After an oil change, the low engine oil light turns on. Now it's as if I have a leak. Need to take the car in for inspection.