1963-1970 Buick Riviera — MPG & Fuel Facts NO OFFICIAL EPA RATING

The EPA's public fuel-economy dataset only goes back to 1984 — the 1963-1970 Buick Riviera predates it, so there is no government-rated MPG number for this car anywhere, including here.

Estimated 10–15 MPG combined.

Motor Trend's April 1963 road test of a 401 'Nailhead' V8/automatic Riviera averaged 13.2 mpg over a 2,500-mile test (11.2 in town to 14.9 on the highway); a later retrospective notes the higher-output 425 'Super Wildcat' GS engine could drop below 10 mpg when driven hard, which sets the low end of this range.

This is our estimate, not an EPA rating — built from the period road tests, marque-specialist guides and corroborated owner reports cited below, hedged where sources vary. Treat it as a ballpark for planning, not a spec to rely on.

The first-generation Riviera (1963-65) used Buick's 401ci 'Nailhead' V8 as standard, with a 425ci Super Wildcat V8 optional; later cars (1966-70) moved to a redesigned 400ci/430ci/455ci V8 family, almost always paired with Buick's automatic transmission (Dual-Range Turbine Drive, later Super Turbine or Turbo Hydra-Matic).

This is the best-sourced vehicle in this batch: a full Motor Trend road test (April 1963, by Jim Wright) was read directly from a scanned original and states 'During the 2500 miles we had the Riviera, it averaged between 11 and 15 mpg on premium gasoline. Overall average was 13.2 mpg... Around-town traffic... gave a low average of 11.2 mpg, while extended highway trips pushed the figure up to a high of 14.9 mpg.' The same article notes Buick offered an optional 2.78:1 'economy' rear axle intended to put consumption 'in the 12- to 16-mpg range.'

Ate Up With Motor's retrospective on the early Riviera (drawing on period Motor Trend, Car Life, Car and Driver, Road & Track, Autocar, and Motor road tests in its bibliography) notes the high-output 425 Super Wildcat GS had 'alarmingly heavy fuel consumption, which could drop below 10 mpg if flogged' -- consistent with, not contradicting, the standard-401 baseline above. Wikipedia's Riviera article independently cites the same 13.2 mpg figure via a print source (Flory, American Cars 1960-1972, 2004, p.210).

Sources: Motor Trend, April 1963, "Buick Riviera" road test (Jim Wright), scan hosted by Over-Drive Magazine · Ate Up With Motor, "Razor-Sharp Style: The 1963-1965 Buick Riviera" · Wikipedia, "Buick Riviera"

All classics Search Buick Riviera on FuelFacts (in case a later model year is in our 1984+ EPA data)