Seventh generation (1973)

1973-1991
Overview
Also called - GMC Suburban / Chevrolet Veraneio (Brazilian version)
Model years - 1973-1991 (1989-1996 in Brazil)
Assembly - Flint, Michigan (Flint Truck Assembly) / São Caetano do Sul, Brazil (Chevrolet Veraneio)
Body and chassis
Body style - 4-door SUV / 2-door SWB SUV (Brazil) / 4-door pickup truck (Brazil)
Layout - Front engine, rear-wheel drive / four-wheel drive
Platform - C/K series
Related - Chevrolet K-Blazer/GMC K-Jimmy / Chevrolet/GMC C/K
Powertrain
Engine - Diesel: 245 cu in (4.0 L) I4 Maxion S4/S4T (Brazil) . 350 cu in (5.7 L) LF9 V8 (1978-81) . 379 cu in (6.2 L) Detroit Diesel V8 (1982-91) / Gasoline: 250 cu in (4.1 L) I6 . 305 cu in (5.0 L) V8 (1976-88) . 307 cu in (5.0 L) V8 (1973) . 350 cu in (5.7 L) V8 . 400 cu in (6.6 L) V8 (1976-80) . 454 cu in (7.4 L) V8
Transmission - Manual: 3-speed . 4-speed / Automatic: 3-speed THM-350 . 3-speed THM-400 . 4-speed 700R4 (1981-91) . 4-speed 4L80-E (1991)
Dimensions
Wheelbase - 129.5 in (3,289 mm)
Length - 219.1 in (5,565 mm)
Width - 79.6 in (2,022 mm)
Height - R10: 72.0 in (1,829 mm) . V10: 73.8 in (1,875 mm) . R20: 74.3 in (1,887 mm) . V20: 76.1 in (1,933 mm)
Curb weight - 5,837 lb (2,648 kg)

For 1973, the Suburban became part of the Rounded-Line C/K series, with both the Chevrolet and GMC divisions adopting the Suburban nameplate. Growing nominally in size over its Action-Line predecessor, the seventh-generation Suburban completely abandoned its carryall past, introducing a station wagon-style body with four full passenger doors (more than a decade after its Wagoneer and Travelall rivals). As the term "sport-utility vehicle" was more closely associated with off-road vehicles (such as the K5 Blazer), GM designated the Suburban as a truck-based station wagon.
From the rear of the passenger doors, the Suburban shared its bodywork (both its doors and roofline) with the C/K crew-cab pickup (a new configuration introduced for 1973). The 1⁄2-ton and 3⁄4-ton 10 and 20 payload series made their return alongside the rear-wheel-drive C-series and 4×4 K-series. Alongside the long-running twin-panel rear doors, the Suburban adopted an optional tailgate-style rear door with a retractable rear window (lowered manually or electrically).
Initially offered in Custom, Custom Deluxe, and Cheyenne Super trims, the Chevrolet Suburban adopted a base Custom Deluxe, mid-level Scottsdale, and flagship Silverado trim nomenclature for 1975. GMC Suburbans were initially Custom, Super Custom, and Sierra Grande; in 1975, Sierra Classic replaced Super Custom. In 1981, GMC replaced Custom with Sierra. A rare variant for both Chevrolet and GMC was the Estate option package, offering woodgrain exterior trim (in line with sedan-based wagons); the option was offered through the 1979 model year.
Though technically fitted with only with a front bench seat as standard equipment, the Suburban was offered in multiple interior configurations, offering up to nine-passenger seating. Bucket front seats became a front-seat option in 1978, with the third-row seat changed to a quick-release design (without tools) for 1979.
The Rounded-Line Suburban shared the same exterior revisions of its pickup-truck counterpart. Along with minor revisions in 1975, 1977, and 1980, the model line underwent a more substantial revision in 1981, followed by updates in 1983 and 1985.
Powertrain details
The Suburban shared several engines with the C/K pickup truck line. A 250-cubic-inch inline-six was the standard engine through 1979. The model line was offered with a 307- (1973 only) and 350-cubic-inch small-block V8s; a 454-cubic-inch big-block V8 was optional in C-series Suburbans. For 1976, the 350 V8 was joined by 305- and 400-cubic-inch V8s; the latter was discontinued for 1981. For 1980, V8 engines became standard for the model line, with the 305 returning as the standard engine for 1981. For 1982, GM introduced a 6.2L Detroit Diesel V8 as a higher-efficiency alternative to the 454 V8.
A 3-speed manual transmission was offered through the 1980 model year, with a 4-speed manual offered through 1987. Initially offered with 3-speed Turbo Hydra-Matic 350 and 400 automatic transmissions, a 4-speed Turbo Hydra-Matic 700R4 became an option in 1981.
For 1980, K-series Suburbans moved from full-time four-wheel drive to a part-time system, allowing the front axle to freewheel. For 1981, the shift-on-the fly 4×4 system adopted automatic-locking front hubs; the NP208 transfer case replaced the NP205 in most examples.
R/V series (1987-1991)
For 1987, GM redesignated the Rounded-Line C/K series as the R/V series to accommodate the launch of the 1988 GMT400-platform C/K trucks, which were being launched in the spring of 1987. For 1987, the gasoline engines of the model converted from carbureted fuel delivery to electronic fuel injection (using throttle body injection/TBI). For 1988, the 5.0L engine was dropped from the line, with the 5.7L V8 becoming the standard engine. In a trim revision, the R/V line adopted the nomenclature of its GMT400 successor, with all vehicles adopting the 1500/2500/3500 payload series (previously used by GMC) and the base Custom Deluxe trim retired and replaced by a revived Cheyenne trim.
For 1989, the exterior underwent its largest revision since its 1973 introduction. Adopting a style similar to the GMT400, the black-painted grille was offered with quad headlights (economy trims were equipped with two). After using the same design nearly unchanged since 1973, the steering wheel was replaced (adopting the same design as the GMT400).
For 1990, the Suburban introduced power-operated sideview mirrors, also adding the option of rear-wheel ABS. Alongside the Suburban and Blazer/Jimmy, the R/V line was pared down nearly exclusively to 1-ton crew-cab pickup and chassis-cab trucks.
For 1991, the 4-speed 700R4 automatic transmission was replaced by the electronically-controlled 4L80-E unit. After an 18-year production run, the Rounded-Line Suburban ended production as GM shifted crew-cab pickup trucks and full-size SUVs to the GMT400 platform for 1992.

1989-1991 GMC Suburban V-1500 Series
1977 GMC Suburban C15 Sierra Classic
1977 Chevrolet C20 Suburban Estate
1979 Chevrolet Suburban C20
1980 GMC Suburban C15 Sierra Classic
1983 GMC Suburban K25 Diesel
1985-1988 GMC Suburban Sierra Classic
1988 GMC R2500 Suburban High Sierra
1989-1991 Chevrolet Suburban 2500 Silverado
1977 Suburban Estate dashboard

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