Matias Sanchez opened the scoring for the Crew after six minutes and Domenic Oduro made the game safe 16 minutes later.
In a battle of the strugglers Toronto came from behind to win 2-1 away to DC United.
Dwayne De Rosario gave the capital club the lead from the penalty spot after 19 minutes but Robert Earnshaw (31) and a Dan Woolard own goal (41) ensured Toronto took the points.
In the cross-conference game the West's Vancouver Whitecaps defeated New England Revolution 4-3.
New England's Andrew Farrell was sent off after 23 minutes, conceding the penalty from which Camilo da Silva pulled a goal back for the Whitecaps after they had gone 2-1 behind following goals from Juan Agudelo (10) and Kelyn Rowe (20).
Vancouver's other goals came from Kenny Miller (39 and 68) and Jordan Harvey (43).
Dimitry Imbongo got a consolation for the Revolution after 84 minutes.
Western Conference leaders FC Dallas lost 1-0 at third-placed Portland Timbers with the only goal of the game coming from Darlington Nagbe after 52 minutes.
The win moved Portland to within two points of leaders Dallas.
San Jose Earthquakes won 2-1 away to 10-man Colorado Rapids with goals from Steven Lenhart (11) and Sam Cronin (52).
The Rapids had to play with 10 men following the 18th-minute dismissal of Atiba Harris, Nathan Sturgis scoring a consolation goal with 23 minutes to go.