Valachio -
The value is the “Screen Size” option. Which can be found here on a per mesh basis.
If the number is grey and cannot be changed, you will notice that check box below it that says “Auto Compute LOD.” You will want to UNCHECK this option to be sure that you can change the value. The SMALLER the number, the further the object is before it drops the LOD. So you will want to make this number very small on any of the meshes that you don’t want the LOD to drop out on. Hopefully that helps!
- Jacob