The last car remarkably lighter than its competitors that I can remind right now is the last-generation Ford Escort.
Ford is not my cup of tea anyway, but it's important to consider how cars got too heavier without some valid excuse, since nowadays a lot of higher-strenght yet lower-weight materials became cost-effective enough for mass production.
As far as trucks go, nowadays that full-sizes often exceed the GVWR limit for a regular driver license in Brazil, even though their payload might not become greater than compact trucks, some models that would be considered a compact or a mid-size in the U.S. are outnumbering full-sizes here.