Dumb question - difference between Dodge and Plymouth

In the 70's I had "some guy" try to tell me that he bought all his parts at a Dodge dealer because they were "better than Plymouth." I had already figured out that is BS because a Chrysler part no is a Chrysler part no. I bought some parts at Dodge because that dealer was closer to the Naval Station, and some I bought at Plymouth.

But it's not ALWAYS "all the same."

I don't know about "currently" but GMC and Chev trucks were traditionally NEVER the same. There were lots of differences including ball joints, wheel bearings, and brakes, up through the seventies

In 55 when Chev first put v8s into pickups, Chev had a Chev V8 and GMC used Pontiac. I don't think "all Chev" engines were used in GMC until 68?

The point is sometimes there are differences. At one time, Merc Lincoln and Ford all had their own engines.