What's killing my lawn it maintained however it loses its sheen then dries out and dies

[Jkantoro]

 

[DirtMechanic]

Looks like heat and drought. The greyish color is something I see on my cool season grasses when it is deep summer and my warm season grasses are flourishing. That is a TTF? You need to dethatch it. Fescues grow too thick for their own good, and add to that a taller grass cut height and suddenly its a choking, suffocating hydrophobic dense mat underneath the blades. You will see as the thatch comes up. Antifungals like cornmeal will help any infection that wants to start due to the packing thatch. Plug aeration is very important too by this time of year for cool season grasses. Its best done when they are growing in the spring or fall, as now their root systems are working underground while the upper part of the plant suffers the off season. But come fall, or as temps wane, your aeration and other works will come back to you as those now well oxygenated and more deeply watered roots find room to grow into the plug holes. Since it has not been done I would aerate regardless and add compost to get a start and then do it again in the fall.