My mother, who has a language barrier, came in for an oil change for a 2013 Lexus GS with 50K miles. The technician told her she needed an engine flush as well. She walked out paying $148.25.
When asked today about why she was given an engine flush, they indicated that her car was 3k miles past recommended oil change, and therefore an engine flush was needed.
This is a classic 3rd party shop that will take advantage of people. Do not go here. If they truly believe a vehicle with 50K miles needs an engine flush, then their knowledge in vehicle maintenance is questionable, and thus any recommendations or work is untrustworthy. If they know such a recommendation is ridiculous, then they with full knowledge and intent are ripping people off.