HiHow can i make large PDF format from Autocad about 900X8000 mm ? the DWG to PDF driver is limited to 5000 mm ! if i convert my large plt file to pdf using viewcompanion for example i lose the layer of my file !!Any Idea ? Thank you

I would use the custom sheet size tip in the AutoCAD tips and tricks section. I work with AutoCAD 2015 lt and Windows 8.1 and have had to add quite a few standard sheet sizes (such as Arch E and ANSI D) since it doesn't seem to like adobe acrobat much. However, making your own set in the print properties section should work.