While the true origins of the nameplate are unknown by Ford historians, the consensus is that is derived from Montclair, New Jersey, an affluent community located near its then-new Mahwah Assembly facility.

[4] As a styling feature, the Montclair received a color-contrast panel below the window line (typically color-coordinated with the roof).

[3] A 292 cubic-inch V8 adopted from the new Ford Thunderbird roadster produced 195 hp; along with a 3-speed manual transmission, a 3-speed automatic was offered as an option.

[9] In addition, childproof rear door locks, seatbelts, and a padded dashboards were introduced as free-standing options.

The 3-speed manual or the optional 3-speed Merc-O-Matic automatic transmission continued, while an additional Touch-O-Matic overdrive was offered separately.

While transparent roofs had been a styling feature of multiple 1950s concept cars (including the Lincoln Futura), the design as a production feature was not widely accepted by consumers, who found interior heat buildup in the vehicle during the summer unacceptable, particularly as air conditioning was not offered as a factory-supplied option until 1956.

In total, only 1,787 Sun Valleys were produced.For 1957, Mercury again revised its sedan line, with the Montclair becoming its mid-range offering, now slotted below the newly introduced Turnpike Cruiser.

[1][12] The model line underwent a revision, as the Montclair four-door pillared sedan now shared its roofline with the Monterey.

[25] One of the largest cars ever produced by the Mercury division, the 1959 Montclair was criticized by owners for lack of interior room (relative to its size), poor fuel economy, and its windshield design.

[26] For 1960, Mercury sedan underwent their second major exterior revision in two years, adopting more restrained styling (nearly removing the tailfins altogether).

[25] For the 1961 model year, to build a better business case for Lincoln-Mercury within Ford, both the Mercury and Lincoln brands underwent a substantial revision of their model lines, with Mercury discontinuing the Montclair and Park Lane in favor of the Monterey as its primary sedan line, joined by the full-size Meteor and the compact Comet, two designs originally intended for production as Edsels.

In a larger change, the 1961 Mercury (both the Monterey and Meteor) adopted a Ford bodyshell and chassis (using its own wheelbase and slightly modified styling).

[28] The 1964 Mercurys underwent a minor facelift, as a convex grille replaced the previous concave design, an appearance shared with the 1961 Thunderbird and the 1961 Lincoln Continental.

Using a 120-inch wheelbase (one inch longer than Ford sedans), the 1964 Mercury Montclair was equipped with a 390 cubic-inch V8, producing 266 hp.

The Breezeway retractable rear window made its return, redesigned to fit within the standard roofline (now opening only several inches to supplement flow-through ventilation[35]).