Veteran Grimsby captain John McDermott got himself on the scoresheet to earn Town's first home goal of pre-season, while Mariners boss Graham Rodger marked his testimonial match in front of a crowd of just over 3,500.
Lewis equalised seven minutes into the second period after good work by Frazer Richardson.
The Whites had trialist Darren Ward in goal and former Sheffield United striker Carl Asaba also featured along with two foreign trialists, former Fulham and Rangers defender Jerome Bonnissel and German Roland Benscheidr.
Jermaine Beckford was denied by keeper Phil Barnes and Gylfi Einarsson also had an opportunity to equalise.
Ward then had a chance to shine when he pulled off a save from Isiah Rankin.
Grimsby Town: Barnes, McDermott (Croft 71), Newey, Harkins, Whittle, Futcher, Toner, Rankin (North 79), Bore (Foy 57), Jones, Beagrie (Hegarty 71).
Subs Unused: Barrick, Chamberlain.
Whites: Ward, Richardson (Madden 65), Bonnissel (Camfield 77), Gregan, Benscheidr, Einarsson (Hird 56), Asaba (Gradner h/t), Bayly, Beckford, Moore (Garra 56, Howson 84), Lewis (Morris 65).
Sub Unused: Wilberforce.