I suggest starting with a soil test if you haven't done one in several years. It will tell you your soil type, pH, fertility and more - helping you to properly fertilize your lawn and have a stronger, denser turf to better resist disease and insect infestation. It only costs $25 and they will provide you with a fertilizer recommendation in addition to the analysis of your soil sample. Knowing the condition of your soil is the starting point to establishing & maintaining a good lawn. More info here: Don't Guess-Soil Test-MSU and

MSU Home Soil Test-self mailer

In the State of Michigan cool season turf grasses grow best.  They include Kentucky Bluegrass, Perennial Ryegrass, Turf-Type Tall Fescue and the Fine Fescues.  More info below on the characteristics and needs of each variety:

Turfgrass species ID & Cultivar Selection (E2912)-MSU

Home Lawns | MSU Extension

Turfgrass species selection-UMass

Establishing A New Lawn Using Seed-MSU

Choosing the Right Grass Seed for a Thriving Lawn-Illinois

It sounds like you need to conserve moisture and a good way to do that in a sandy soil base is to add organic material (compost, rotted leaves, etc.) to your lawn.  Get it into the soil a bit quicker by core aerating your lawn (rent a machine at a rental company) and raking compost over the yard afterward (leave the cores on the lawn).  Mulch your leaves into the lawn each fall (I pickup bagged yard waste leaves in November to do this to my lawn).  Organic material will help conserve moisture and provide nutrients for your turf.  Also, mow your lawn as high as you can (>3.5") as taller turf means deeper roots to get at moisture.  Here are links to more articles you may find helpful:

Core Aeration of Lawns-MSU

Why Mow High-MSU

Smart Lawns Tip Sheets-MSU