The tri count on LOD0 is pretty high, which will require a fair bit of power to render, especially if there are a lot of objects on screen.
Each LOD (level of detail) has progressively simpler geometry, making each one easier to render than the last. The game will choose a version of the model based on the distance the model is from the camera.
For LOD1, I decrease steps viewport in the screw modifier from 16 to 10.