Cleaning up around the house I noticed the main ground wire is in pretty rough shape. When I say rough shape it's only got a couple of copper strands holding it to the ground rod. Could I sink a new ground rod right next to the old one and run it into the house where the ground wire is not damaged and connect it with a split bolt?

Are you sure you are talking about a ground wire and not a "Guide Wire" or Guy wire from the pole?

Cleaning up around the house I noticed the main ground wire is in pretty rough shape. When I say rough shape it's only got a couple of copper strands holding it to the ground rod. Could I sink a new ground rod right next to the old one and run it into the house where the ground wire is not damaged and connect it with a split bolt?
I'm sure. The wire I'm talking about connects to a ground rod on the backside of the house. The meter box and all wires from the pole are in front.

Since the grounding electrode conductor is very important, much to everyone's surprise, if it needs to be extended or added to, a split bolt connection is not allowed, ever.

Any connection or splice must be irreversible. There are two methods that will suffice, either a crimp connector, or a Cadweld connection.

A crimp connection will need the crimp connector, plus a special crimp tool that may not be readily available to a DIY'er. You may find a distributor that rents the crimping tool with the proper die for the crimp connector.

The Cadweld method is for professionals only, for several reasons. Do a web search if your interested in more detail.

You will be much better off replacing the entire grounding electrode conductor from the panel to the ground rod(s). The wire needs to be a min of #6 copper if only connecting to rods.

Aluminum wire is not allowed for this.

In addition to above, be careful when disconnecting wire from ground rod as voltage MAY be present. You could turn off Main to be Extra safe, or be aware and measure voltage disconnected to verify not live, or Isolate.
If voltage present, you could turn off breakers to determine what circuit(s) are leaking to ground.