diff --git a/test/gtest_factor_diff_drive.cpp b/test/gtest_factor_diff_drive.cpp
index 8283b62b8ef35e591dad8533256a517ad65f7718..c37bed03e30da209b9b644d49b92011afeeb5f93 100644
--- a/test/gtest_factor_diff_drive.cpp
+++ b/test/gtest_factor_diff_drive.cpp
@@ -626,7 +626,7 @@ TEST(FactorDiffDrive, preintegrate_and_solve_sensor_intrinsics)
 
     // right turn 90 deg in N steps --> ends up in (1.5, -1.5, -pi/2)
     int N = 6;
-    Vector3d data;
+    Vector2d data;
     Matrix2d data_cov; data_cov.setIdentity();
 
     data(0) = 0.50*intr->ticks_per_wheel_revolution / N;