diff --git a/test/integration/wheel_slip.cc b/test/integration/wheel_slip.cc
index b56f1e3a50..52f562e76a 100644
--- a/test/integration/wheel_slip.cc
+++ b/test/integration/wheel_slip.cc
@@ -558,8 +558,11 @@ TEST_F(WheelSlipTest, TricyclesUphill)
   // normal force as passed to Wheel Slip in test world
   const double wheelNormalForce = 32;
   const double mass = 14.5;
+  // Slip works on DART>=6.10, which isn't available on Ubuntu Focal
+#ifndef __linux__
   const double forceRatio =
     (mass/2) * std::abs(gravity->Data().X()) / wheelNormalForce;
+#endif
   const double noSlipLinearSpeed = wheelRadius * angularSpeed;
 
   auto wheelRearLeftVelocity =