I dunno. I couldn't find the specs of the original terra grappler on the nitto website.

I found the G2's specs and the diameter is 31.46" inflated.
I found the specs for LT version of the original grappler and it is 31.50.

But from eyeballing the photos, it looks like the shape of the G2 might be wider at the outer edge which could be a problem when turning.