M-37 parts East Beltline Avenue and turns west along I-96. The freeway runs west and then north around the edge of Grand Rapids. Near 3 Mile Road, I-96/M-37 runs west again, continuing across the Grand River and meeting the US Highway 131 (US 131) freeway. The next interchange immediately west of US 131 is for Alpine Avenue, which M-37 follows north. This road runs through a commercial and retail corridor in the communities of Walker and Comstock Park. South of 6 Mile Road, Alpine Avenue widens into a four-lane divided highway. This highway splits from Alpine Avenue north of 8 Mile Road and turns to the northwest as the surroundings transition to rural farmland again. M-37 transitions back to a two-lane road south of Sparta. The trunkline passes to the west of Kent City and crosses into Muskegon County at Casnovia. Through this area, the highway parallels a line of the Marquette Rail that runs north from Grand Rapids.