So far as I can see (just a quick look),
ELF's Sable has the best 6-cylinder mileage @ around 27.6.
My old '99 TL may have been a distant 2nd (final retired mileage = 24.35). Not a whole lot of 6's around...
Best 8 is race prepped
2002 Z28 of Coyote X's.
RH77
EDIT: I didn't see the RAV-4 -- definitely a winner. Tessie (#120 @ 28.49mpg) is actually a 4-banger. The 90-day avg. of the "Champion" Town Car is close to the Z.
EDIT-II: If the RAV-4 is the base (pic is the V-6 model), it has the 2.4L, 4-cylinder -- which defaults to the Sable (3.0L V-6).
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