On Sat, 12 Sep 2020 04:17:13 -0700 (PDT), "Dr. Deb"
wrote:

On Friday, September 11, 2020 at 6:54:41 PM UTC-5, DerbyDad03 wrote:
I was attempting to install a hidden hitch on my van today. Before I reached
the specified torque given in the instructions for one of the 10mm bolts, the
weld nut on the vehicle stripped. The bolt still threads in, but never
tightens fully. It's not the bolt, it's the weld nut.

There is no access to the weld nut from under the vehicle. There is nothing
strong/thick enough in the area to drill through for a nut and bolt.

I'm thinking of tapping the 10mm weld nut to 12mm and using a 12mm bolt for
that one hole.

As described in the image below, there are two 12 mm bolts that hold the
hitch on the vehicle's frame up from the bottom (one on each side) and four
10mm bolts that go through the face of the hitch into the holes that also
hold the bumper bar into the frame. The facia then covers the bumber bar and
hitch, leaving only the receiver showing.

The upper right 10mm weld nut is now stripped.

All suggestions welcome. Thanks!

https://i.imgur.com/08cHQDV.jpg

J. Clarke's helicoil suggestion is the way I would go. Its a bit more work, but you will have hardened threads, vs what you have now.

Just to give credit where it is due, Clare came up with the helicoil
suggestion. I just added my 2 cents worth.