We are getting a new gas range and we didn't know if the current gas valve should be replaced or not since it is an old valve. It looks like it is outdated and needs to be replaced. Should we get this replaced?
If you're concerned that the valve is ok, call your local gas company. They'll come out to re-light pilots, and will also come out if you have any questions about something you're doing with any gas lines.
They really don't want you to have any problems. They will also do easy simple repairs, but tell you to get a pro to fix something bigger. For example, I called them once about the gas valve to our pool heater was really tight, it seemed to be rusted and I couldn't close it. The gas guy came out, took the nut off the back, pulled it apart and applied some grease and it was like new. It was apart for only about 20 seconds and he didn't even shut off the gas! He also checked the heater that it was working ok.
The valve pictured needs to be replaced immediately please. That type of valve is not only out of code but few know that it needs regular grease maintenance every few years, now ask yourself has this been greased in the last 10 years or 20? I think not. Spend the time and put a ball valve so in an emergency you will not have to find a tool to shut it off if the appliance developes a leak. My mother in law had a 5 year old gas stovetop go poof on her last year, luckily it just scared the pants off her but the inner explosion was forceful enough to unseal the stovetops gasket connecting the factory upper half to lower half. Leak was caused by maids over cleaning and getting cleaner over the years down into casing by spraying stovetop with cleaner. The cleaner along with any spills caused the dissimilar metals of the gas tube and appliance casing touching and caused a hole is my best theory after dismantling and inspection of the unit. Be safe replace it and make sure to add a auto off check valve also. But hey its only the life of you and your family we are talking about over 10 dollars in parts.