Low oil pressure warning - need new engine?!
 

My 2018 Limited has run perfectly from the start. I love the truck and have always had the oil changed with high-grade synthetic when prompted. It's been three weeks since my last oil change. A couple days ago the low pressure warning came on and the engine went into safety mode. I took it to the dealer thinking it needed a sensing unit, only to be told there is sludge build-up and I need a new engine. I am wondering how common this is with the Eco boost and what ideas anyone might have to avoid an engine replacement? The engine sounds just fine, no unusual noises. When I start it and drive for a mile or so it runs will full power, but then the warning comes on and it goes back to safety mode. I have two vehicles over 20 years old each with the Tritan V10 and they still run perfectly with nothing but oil changes. Can't wrap my head around this.

Thread from the dead, but I'd get another opinion. What oil do you use and what is the interval?