Using Gazebo 5 to simulate a robot, how do I add more noise/drift to the transforms/odometry ?

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I'm trying to measure the performance of AMCL under changes in Lidar specs, such as max range, update frequency, FOV, and other things. But it turns out that in simulation from gazebo that odometry has so little noise/drift that AMCL performs very well whether I use a simulated 30 meter long laser or a 1 meter long laser. This happens even in large featureless rooms.For example, over the course of 60 seconds of driving the 1 meter long laser only saw a wall for half a second. Yet the performance of AMCL on that run is comparable favorably to the run with the 30 meter long laser.

Any help would be greatly appreciated. I'm relatively new to ROS, I just started using it less than two months ago so please bare with me if I have any follow up questions, thank you very much.

EDIT: I don't know if it helps but I am using the gazebo plugin for differential drive robots. I don't know if it's possible to alter it somehow to add more drift/noise.