How to do surface modeling in drawing saved down from 2018 to use with 2017

Why is the latest version in True View 2013? I have to do a volume surface for a client. I received a drawing from the primary engineer that was created in 2018, so I could not open it in my 2017. I asked her to save it down and resend which she did, to 2013. I didn't know why until I had IT download TrueViewer, and see that that is the latest option. Now when I try to use their contours to create a surface it tells me I can't because the objects were created in a newer version......

Please tell me there is a way to do this. I tried copying the ex and prop contours to a new drawing...nope. Thank you for any help you can give

Have her export the surface out to landxml and then bring that in.

2018 and 2017 don't talk to each other, both on the CAD side and the C3D side. On the C3D object side saving down 2018 drawings dumbs the objects down so earlier versions can open it, which is what you're seeing, but since they don't talk to each other on the CAD side that's why you're still running into issues. If this was a 2017 to 2016 situation (2016 and 2017 CAD can talk to each other) I don't think you'd be having this problem.

Either way, I just double checked by exporting out my 2018 surface and bringing it into 2017 and it worked fine, so that should get you what you want.

Civil 3D drawings, for the most part, are NOT compatible. Drawings created in versions 2004-2012 can only be worked on in the same version or upgraded to a later version. If upgraded to a later version, it cannot go back down (which is what you're trying to do).
There are a couple of exceptions, drawings created with versions 2013-2016 can be worked on in any of those versions, and the same applies to 2018-2019.

It's best to prepare ahead of time and plan on all parties to use the same version of C3D.

See also:

https://i.imgur.com/fCfILlM.png

Here is the way it works, export the surface landxml. Or turn on contours and 3d faces then export the dwg back to the version wanted. Only surface items visible will be exported back as primitives that you can recreate the same surface from.