Two ways that this can be handled (there are more):

1. For each view where you need to hide the grids, open the Visibility Graphics dialogue; Go to the Imported Categories tab; Under the Visibility column click the + symbol next to the DWG name; uncheck the layers that you want to hide.

2. In the view itself, select the DWG by clicking on any of it's graphics; on the ribbon you should now see a panel called Import Instance; on this panel click Query; now click one of the grid lines that you want to hide and this will open the Import Instance Query panel; click the Hide in view button to hide the layer.

If you have a lot of views, I'd consider editing a copy of the original DWG to remove the graphics that you don't want to see and then reload the link from the edited DWG.

Hi Philsogood, you can hide layers from cad files at any moment by clicking on the CAD file and by looking for the tool called Query if your Revit is in English or "Requête" for a French version (See image) once then you have the possibility of hide the selected layer or delete, hope this can help

hi
i knew theses 2 technics but i'd like to do not see the grids of the cad file on all views so :
i place my cad file (with the grids), i mark one corner of the file with lines
i erase/delete the cad file, freeze, the grid in the cad file import the cad file(without grids) and use the lines i buildt to place the file in the right place
i delete the lines and it's ok...
i know that on RVT file we can modify (hide or not) workset directly from the manage link wndow, iguessed that there was some option like this for DWG!!
thanks
Phil
Ps : in that way i don't need to modify the DWG and to increase the dwg files!!