Hi @22122864
With the next workflow, you´ll get clean models, which is necessary 3ds max software for these results.
1. In SketchUp:
Export the 3D Model with .3ds extension.

2. In 3ds Max:
Import the .3ds file



By default, the geometry is imported without the diagonal lines:

Now, with the cleaned geometry, export the file to the .dwg extension.


Please select the "AutoCAD 2004 DWG" version for the entities in AutoCAD will be Polyface Meshes (if you don't export in the version, the results will be Meshes), The Polyface Meshes cab be stretch and don't have a high weight.

3. In AutoCAD:
You can open the .dwg file and the entities look like this:

If you select any entity, the type is a Polyface Mesh 😊.

In addition, as a result of exporting from 3ds max to Autocad, a layer has been created "Ashade", which appears locked, and cannot be purged; and, the color of the layers has changed.

About the Ashade Layer:
Please, Unlock the Ashade layer and invoke the LAYDEL command, then Name Option and select the Ashade layer in menu.


Confirm if you are sure...

And... the layer disappear 😎

About the color, I recommend changing the colors for new in the Intex Color Tab.
Well, I hope I have not extended too much.
Please let me know how it works for you. 😉
Johanna Esteban

Autodesk Expert Elite | Autodesk Certified Professional | AutoCAD Customer Council (Beta Tester for Windows & Mac)
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