2011 Dodge Durango overheating. Changed radiator, thermostat, and water pump. Dealer says there must be blockage in the engine.

What is your question?

Dealer first tried an engine flush, then a chemical flush, no success. White "pellets like sand" was coming out. Dealer claims wrong antifreeze was used, but that is not correct.

What makes this problem better or worse?

Car will drive if no thermostat is used.

How long has your 2011 Dodge Durango had this problem?

Since mid November, 2020