83 year old still driving, but not good. Any suggestions?

How does she drive that is causing you concern?

I would discuss this with her physician and ask if she could be assessed by an occupational therapist that specializes in driving assessment. AARP has articles on their website that explains this more. Also, the occupational therapist can suggest modifications so that she is safe driver.

LivWithMom, I came across this article about elderly drivers, it has some good information: https://www.agingcare.com/articles/worried-about-elderly-parent-driving-133862.htm

See if the DMV will test her. If not, maybe her Doctor can evaluate her and report that she can't drive to DMV. They will take her licence away.