Mark money in checking as "Set aside" for future expense

We want to set aside money in our checking account to buy a car. Currently, we just create a "virtual" expense in the near future and mark it as "New car". As our checking balance fluctuates, we update that virtual expense to maintain a healthy balance. We also update the date to keep it in the future but in view in the register.

I'm thinking there has to be a better way...thoughts