Buick LeSabre Gen 4
Reviewed by Unique Cars and Parts
Our Rating: 3
1971 Buick LeSabre
Like the other GM divisions, Buick completely restyled its B- and C-body cars for 1971. The full-size cars emerged larger and heavier than before and also ever after. The styling featured curved bodysides, long hoods and wide expanses of glass, similar to that of Chrysler Corporation's 1969 full-sized cars, but with a lower beltline than the Chrysler products. Semi-fastback rooflines were utilized on two-door hardtop coupes and convertibles had a new top design to permit a full-width rear seat.
1972 and 1973 Buick LeSabre
The same assortment of 350 and 455 cubic-inch V8s were carried over but featured lowered compression ratios and other modifications in order to enable the use of lower-octane low-lead or unleaded gasoline as a result of a General Motors corporate mandate. Variable-ratio power
steering and power front disc brakes were made standard equipment on all LeSabres at the start of the 1971 model year. A few months later in March, 1971 the Turbo Hydra-matic transmission became standard equipment, and all Buick LeSabre's and would remain so equipped in base form for the next 35 years until the marquee's final year in 2005.
The new body also featured a double shell roof for improved roll-over protection. Also new for '71 was a flow-through ventilation system utilizing vents mounted in the trunklid shared with other full-sized GM cars and the compact Chevrolet Vega. It used the heater fan to draw air into the car from the cowl intake, and force it out through vents in the trunk lid or tailgate. In theory, passengers could enjoy fresh air even when the car was moving slowly or stopped, as in heavy traffic. In practice, however, it didn't work.
However, within weeks of the 1971 models' debut, Buick and all other GM dealers received multiple complaints from drivers who complained that the ventilation system pulled cold air into the car before the heater could warm up and could not be turned off. The ventilation system was extensively modified for 1972. Also new for the 1971 was an optional MaxTrac computerized traction control system.
Inside was a new wrap-around cockpit style instrument panel that placed all controls and instruments within easy reach of the driver, along with easier servicability with instruments and switches accessible from the front when the faceplate was removed. The seats of a new full-foam design with headrests more squared off than 1969-70. Again, base and Custom model LeSabres were offered in the same sedan and coupe bodystyles while the convertible was a Custom-only offering. The LeSabre 455 model line was dropped for 1971 with the larger engine now being offered as an option on the regular base and Custom-series models. LeSabre Customs equipped with the optional 455 engine got a "455" badge underneath the LeSabre nameplates on the front fenders instead of the "Custom" badge normally used.
A revised grille and taillights lenses were among the styling changes for 1972. Out back, a small "BUICK" nameplate was located above the right side taillight replacing the larger block letters spelling "B U I C K" across the lower trunklid between the taillights in 1971. Also new for '72 was a larger 5-mph front bumper introduced a year ahead of a federal safety mandate requiring such bumpers in 1973. Interior trims received only slight revisions from 1971. A revised flow-through ventilation system utilizing vents in the door jambs replaced the troublesome system used in 1971 with the trunklid vents.
Both the 350 and 455 V8s were carried over from 1971 with horsepower ratings switched the new SAE net figures based on an engine as installed in an automobile with accessories and emission controls hooked up, rather than the gross horsepower method of past years based upon a dynameter rating from an engine not installed in a vehicle. With that, the standard 350 two-barrel V8 was rated at 160 net horsepower compared to 230 gross horsepower in 1971 while the top 455 V8 was rated at 250 net horsepower in 1972 compared to 315 in 1971. Engines were also revised to meet the 1972 federal and California emission standards with California-bound cars receiving EGR
valves, which would be installed on engines of virtually all automobiles for nationwide sales in 1973.
Inside, the instrument panel featured a new "FASTEN SEAT BELTS" light due to a new federal safety regulation and the buzzer which sounded when the key was left in the ignition also sounded upon starting the car to remind the driver and passengers to buckle up. A larger federally mandated 5 mph front bumper and new vertical bar grille highlighted the 1973 LeSabre along with revised taillights set in the rear bumper. Both the 350 and 455 V8s were revised with EGR
valves used on both federal and California-emission equipped cars. The LeSabre Custom convertible was dropped this year leaving the short-lived Centurion as Buick's only ragtop that year as the intermediate Skylark (replaced by the Century for 1973) lost its ragtop completely after the 1972 model year.
1974 Buick LeSabre
New grilles and taillights along with a 5 mph rear bumper highlighted the 1974 Buick LeSabre. Four-door pillared and hardtop sedans retained the same rooflines as 1973 but the two-door hardtop coupe featured a new roofline with a side rear opera windows. Inside, the instrument panel was substantially revised but retained the wrap-around theme. A new (and seldom ordered) option was an "Air Restraint System" which included driver- and passenger-side airbags along with a unique four-spoke
steering wheel. This option, also available on Electra 225s and Rivieras as well as full-sized Oldsmobiles and Cadilacs, was not very popular and was dropped after the 1976 model year.
New integrated seat and shoulder belts were introduced this year along with a federally mandated interlock system that required the driver and right front passenger to buckle their seat belts in order to start the vehicle. The interlock was met with such a major public outcry that Congress rescinded the interlock regulation in late 1974 after a few early 1975 models were so equipped, permitting owners of all 1974 and the early 1975 models equipped with the interlock system to legally disconnect it. With the Centurion line discontinued after 1973, LeSabre was now Buick's only B-body full-sized car. The base LeSabre was continued, but a new LeSabre Luxus series replaced both the LeSabre Custom and the Centurion. The Luxus convertible also returned the ragtop to the LeSabre line after a one-year absence and was Buick's only ragtop.
Engine offerings were revised for 1974. The 350 two-barrel remained standard on all models with optional engines including a 350 four-barrel and 455 four-barrel V8s, both carried over from 1973 with revisions to meet the 1974 emission standards. New engine options for 1974 included a 455 two-barrel and the Stage 1 455 "performance package" which added dual exhausts, suspension upgrades and other equipment. New options for 1974 included radial-ply tires, GM's High Energy Ignition and a "low fuel" warning light that illuminated when the fuel tank was down to four gallons. This would be the final year for the MaxTrac electronic traction control system as an option.
1975 Buick LeSabre
The upscale LeSabre Luxus designation was dropped and replaced by the LeSabre Custom nameplate. 1975 also was the first year of the catalytic converter, and standard high energy ignition which was part of GM's Maximum Mileage System at the time Introducted in September 1974. The 1975 LeSabre was the first to require use of unleaded gasoline, due to the advent of the catalytic converter. The LeSabre lineup offered a coupe and two sedans while the LeSabre Custom lineup offered the coupe, two sedans, and the only convertible in the Buick lineup. 1975 would be the final year for the LeSabre Custom Convertible with around 5,300 examples rolling off the assembly lines.
Engine offerings were simplified and reduced to just two including the standard 5.7-litre V8 (350 CID)and a four-barrel carburetor or optional 7.5-litre V8 (455 CID) with a four barrel. Bodylines on the 1975 were somewhat softer than the 1974 model featuring round headlights side-by-side and a cross-hatched patterned grille that flowed across the front of the car and under the headlights. Turn signals were located in the front bumper. A Buick tri-shield hood ornament was standard on the Custom Series and optional on the base series. The three-hole 'ventiports' were moved from the hood to the front fenders. Slightly larger taillamps than the 74 draped the back of the car with back-up lights positioned in the center broken up by the license plate. Four-door pillared sedans received a new small third windows to emulate the six-window "Colonnade" styling of GM intermediates while four-door hardtop sedans had new opera windows.
Inside, a new flat instrument panel shared with Electra and Riviera replaced the wrap-around cockpit dash of previous years and featured a horizontal sweep speedometer that read to only 100 mph compared to 120 mph in previous years and also included kilometer readings. Otherwise, interior trimmings received only minor revisions. Convertible production for both the LeSabre Custom and the Centurion convertibles were not very abundant in the years 1971 to 1975. The rarest production in that time was the 1971 LeSabre Custom with just over 1,800 units built, and the most produced was the 1973 Centurion with slightly over 5,700 units built. Due to this very low production volume and the end of the full-size convertible era, this may make this series of ragtop LeSabre Custom and Centurion Convertibles quite collectable - depending on the vehicles' overall condition. The convertible mechanism used was called the 'scissor top' that folded inward on itself, instead of straight back. This was featured on all GM full-size convertibles from 1971 to 1976.
1976 Buick LeSabre
Only minor styling changes highlighted the 1976 Buick LeSabre, which was the final year for the 1971-vintage bodyshell, the unpopular and rarely ordered driver- and passenger-side airbag option, the 455 V8 and hardtop bodystyles. Changes amounted to rectangular quad headlights, eggcrate grille and turn signals located just below the headlights. The 1976 LeSabre was the only American full-size car with a standard V6 engine, which was Buick's brand-new 3.8-litre (231 CID) V6 engine. The V6 was only offered on the base-level LeSabre and not mentioned in initial 1976 Buick literature issued in September 1975 because the V6 engine was a last-minute addition to the line. The 350-cubic-inch V8 was the base engine on the LeSabre Custom and the 455-cubic-inch V8 was optional. Both V8s were optional on the base LeSabre.
