Before 96 or so that is how it worked. The theory is if the neutral lands on the same bus as the GEC, it is ground. Once you get a ways down a feeder neutral is not ground anymore. Phil Simmonds pointed out that neutral is not ground on the load end of a branch circuit either and he got his change accepted. He said "The war is over"
We have an amendment within the NJ adopted version of the NEC that allows it still today, IF it's a replacement appliance, AND the mfg installation paperwork does not accept it. That said, 99.9% of the guys install a 4 wire feeder for appliances. (Period)
The ironic thing is most of these I saw prior to 96 were still installed with 3 wire w-g Romex and they either clipped off the ground or bonded to to the box with the neutral landing on the 3 prong receptacle. Putting in the 4 prong might be as simple as just swapping it out.
No,this one is around 50 or 60 years old. Range wire was old #6/3 with insulation cracking at range outlet terminals, not to mention a jumper off it of 14/2 feeding a dryer on the opposite side of wall:( and another jumper off of one leg feeding a 120 volt outlet behind the range:( Needless to say, after the feeder going through the brick outside blew up and started smoking, I'm changing the service. What a nightmare it started out to be, but it's taking shape now. Hopefully I'll finish it tomorrow. Got her some temporary power for tonight. Never a dull moment in electrical work.