Pontiac Bonneville

The Pontiac Bonneville is an automobile built by Pontiac from 1957 to 2005. Bonnevilles were full-sized, with the exception of a brief period of mid-size between 1982–1986. The brand was introduced as a limited production performance convertible during the 1957 model year. The Bonneville (known as the Parisienne in Canada until 1981), and its platform partner, the Grand Ville, are some of the largest Pontiacs ever built; in station wagon body styles they reached just over long, and at and more were also some of the heaviest cars produced at the time. They were also used as a basis for various specialty cars such as hearses.
Early development.
The Bonneville name first appeared in 1954 on a pair of bubble-topped GM Motorama concept cars called the Bonneville Special, sharing an appearance with the Chevrolet Corvette.
It entered the production lineup as a high-performance, fuel-injected luxury convertible version of the Star Chief in 1957, and was loaded with every available option as standard equipment with the exception of air conditioning and a continental kit. This put the Bonneville in a Cadillac-like price range of US$5,782.00 ($ in dollars ) - more than double the base price of the Chieftain on which it was built, with the result being a fully equipped Bonneville could cost more than a larger, entry-level Cadillac. Only 630 units were produced that first year, making it one of the most collectible Pontiacs of all time. The following year it became a separate model, and it would endure until 2005 as the division's top-of-the-line model. The name was taken from the Bonneville Salt Flats in Utah, the site of much early auto racing and most of the world's land speed record runs, which was named in turn after U.S. Army officer Benjamin Bonneville.
First generation (1958).
Bonneville became a separate model in 1958, available as a two-door hardtop or a convertible. It paced the Indianapolis 500 in its first year. As a separate model Bonneville had a significantly lower price tag of around $3,000 thanks to the demotion of most of the luxury items found on the 1957 Star Chief bodystyle from standard equipment to the option list. Also a V8 with four-barrel carburetor and dual exhausts was now standard equipment. The fuel-injection system offered with the standard engine on the 1957 Star Chief bodystyle was now listed as an extra cost option but very few 1958 Bonnevilles were so equipped due to a towering option price tag of US$500 ($ in dollars ), which was not considered a very good value considering that for US$93.50, a more reliable Tri-Power option was available with three Rochester two-barrel carburetors and similar power. The electric clock was standard.
For 1958, GM was promoting their fiftieth year of production, and introduced Anniversary models for each brand; Cadillac, Buick, Oldsmobile, Pontiac, and Chevrolet. The 1958 models shared a common appearance on the top models for each brand; Cadillac Eldorado Seville, Buick Roadmaster Riviera, Oldsmobile Holiday 88, Pontiac Bonneville Catalina, and the all-new Chevrolet Bel-Air Impala. 1958 was also the year the "Silver Streak" styling feature was no longer offered, which was first used in 1933.
Second generation (1959–1960).
In its third year, the 1959 Bonneville became a full top-line series with the addition of the four-door hardtop sedan and Safari station wagon body styles. The Bonneville played an important part that year in the introduction of two of Pontiac's greatest marketing inspirations — the split grille and the Wide Track slogan. The latter was not just ad copy, either, as Pontiac pushed its wheels further out toward the fenders than anyone else and created what were considered to be the best-cornering full-size cars in the industry. Both the grille design and the Wide Track phrase remained part of Pontiac's image up to its termination. A "Safe-T-Track" differential, used to minimize wheel spin, was an option beginning in 1959.
Third generation (1961–1964).
The Bonneville remained Pontiac's costliest and most luxurious model throughout the 1960s and was instrumental in pushing Pontiac to third place in sales from 1962 to 1970.
The distinctive protruding grille made its appearance on all Pontiac products during the early 1960s, and was a modern revival of a similar appearance on Pontiac products during the 1930s and early 1940s, as demonstrated on the Pontiac Torpedo.
The Bonneville differed from its lesser Catalina and Star Chief counterparts by featuring more luxurious interior trim with upgraded cloth and Morrokide vinyl or expanded Morrokide upholstery in sedans and coupes, expanded Morrokide in Safari wagons and genuine leather seating in convertibles. Bonnevilles (with the exception of Bonneville Safari station wagons) were also (along with Star Chiefs) built on a longer wheelbase version of GM's B-Body. Also found in the Bonneville were instrument panels and door panels with walnut veneer trim, carpeted lower door panels, grab bar on the passenger side of the dash and courtesy lights and a rear arm rest. Beginning in 1964, a Bonneville Brougham option package was available that included an even more luxurious interior trim level with front and rear seats featuring center armrests, upgraded door panels and a standard Cordova (vinyl) roof with "Brougham" nameplates. The two-door hardtop was marketed as the "Sports Coupe", the four door pillarless models were called "Vistas".
Bonneville models were standard equipped with Hydra-Matic (through 1964) or Turbo Hydra-Matic (1965-on) automatic transmissions. Options included power steering and power brakes as well as air conditioning. Other popular options included power windows, power seats, radio, cruise control, and 8-lug aluminum wheels that included integral brake drums for improved stopping power. The Bonneville, also, had more powerful standard V8 engines than other full-sized Pontiacs, including the or V8s with four-barrel carburetors (power ratings of depending on year) with many optional V8 offerings, such as the availability of the Tri-Power (three two-barrel carburetor) options on both the and V8s that offered up to through 1966. For 1963 only <1963 Pontiac shop manual>, Pontiac offered the Super Duty with two four-barrel carburetors, rated at , as a US$2,250 option (when the base Bonneville listed at US$3,349).
Fourth generation (1965–1970).
In 1965 B-Body Pontiacs received a dramatic re-style, featuring fastback rooflines on coupes, rakish fender lines and even more pronounced "Coke Body" styling. Bonnevilles followed largely the same styling cues as on other 1965 Pontiacs, but was 8 inches longer thanks to its new 124-inch wheelbase chassis. The interior featured new instrumentation and dashboard styling as well as new upholstery.
Engine options remained unchanged from the 1964 model year, with a, 333 hp unit being standard, equipped with a Carter AFB 4-barrel carburetor. A engine was an optional upgrade. Both engines had choices of Tri-Power multi-carburetion setups and higher compression ratios.
New for Pontiacs in 1965 was GM's Turbo-Hydramatic 400 transmission, which was released the year prior. This new 3-speed unit had a torque converter, unlike the old fluid-coupling based Super-Hydramatic featured on past Bonneville models. The new transmission also changed the shift pattern from "P-N-D-S-L-R" to a safer and ultimately more modern "P-R-N-D-S-L."
In 1965 Pontiac Motor Division received the Motor Trend "Car of the Year" award. As part of this award, Motor Trend reviewed GTO, Grand Prix, Catalina 2+2 and Bonneville.
In 1966, Bonneville featured a minor update, with new front and rear sheet metal, trim and bright work. The interior saw some updates, including a more squared-up dashboard and minor changes in instrumentation. Power train components were the same as 1965.
Bonneville for 1967 received a major update over the previous years. Styling was changed dramatically and featured a new grille-in-bumper front design, more creases to accentuate the "Coke body" styling and an updated rear fascia. The interior featured a new wrap around style dash with new switchgear, instrumentation and trim. As per the up-and-coming US Title 49 legislation, 67' Bonnevilles were equipped with seatbelts as standard, as well as other government mandated safety equipment.
1967 also saw a large power-train and chassis refresh for Pontiac. The 389 cubic inch plant was replaced with one, and the 421 cubic inch plant was replaced with a one. As per GM's internal edict, the multi-carburation setups found on earlier cars were replaced with the new Quadra Jet "spread bore" carburetor. Carter AFB carburetors were still standard, but the Quadra Jet was featured as the new "High performance" upgrade. A myriad of horsepower ratings were optional. A dual-circuit master cylinder was standard as per legislation and disc brakes became an optional extra.
1968 also saw a large styling update for Bonneville. The front fascia was heavily revised with new side-by-side headlights, however, the side and rear styling stayed largely the same from 1967. The interior saw some minor updates to styling with less chrome, as well as an available 8-Track Tape player.
Power was upgraded to 340 horsepower on the base 400 CI engine, up from 333 on the 1967 model year, the 428 CI engine remained an option
In 1969 the rest of Bonneville's styling was updated. The front fascia stayed similar to 68', however, the rest of the car saw a re-style. The creases on the side were removed and the overall "Coke Bottle" effect was lessened. The rear end saw widened taillights and a color coded bumper insert. The interior saw even more updates, featuring more padding, wood trim and a slanted dashboard.
Power trains were upgraded to a standard 360 hp 428 CI engine.
1970 saw the most dramatic update to styling for Bonneville, featuring an entirely new front fascia, with more square features and an updated vertical twin grille design. Wrap around amber turn signals were integrated into the lower bumper. Side body lines remained similar to the 69' model year, however the rear design was completely revised with lowered tail lights and bumper, with a design more similar to that of 65' and 66' model years than those directly prior.
The interior stuck to a design similar to 69' model years, retaining the slanted design and minimal chrome trim.
A new V8 was made standard for the 1970 model year, with the 400 CI engine being an option.
Fifth generation (1971–1976).
For 1971, the Bonneville was downgraded in the model hierarchy, as a new top line Grand Ville series was introduced. In effect, it replaced the discontinued Executive above the lower-priced Catalina. The Bonneville had new "Monocoque" styling and was offered in three body styles, a pillared four-door sedan, four-door hardtop sedan and two-door hardtop coupe. The standard engine for 1971-72 was a 455 cubic-inch V8 with two-barrel carburetor that was rated at 280 gross horsepower for 1971 and 185 net horsepower for 1972 and optionally available was the four-barrel version of the 455 rated at 325 gross horsepower in 1971 and 250 net horsepower in 1972. The on-paper power ratings reflect the change in power measurement undertaken by the industry for 1972. 1971 was also the first year for Pontiac and other GM divisions to reduce compression ratios on all engines across the board to operate on lower-octane regular leaded, low-lead or unleaded gasoline, reflecting a corporate edict anticipating the introduction of catalytic converters in 1975 to help meet increasing stringent federal (and California) emission requirements.
In mid-1971, a Turbo-Hydramatic transmission, power steering and power front-disc brakes became standard equipment on Bonneville and other full-sized Pontiacs (as well as other full-sized GM cars).
From 1973 to 1976, the Bonneville's standard engine dropped to a 170-horsepower 400 cubic-inch V8. Optionally available was the 455 four-barrel V8 rated at for 1973-74 and 200 for 1975-76. In 1973, Bonneville was the only full-sized Pontiac to offer a "Radial Tuned Suspension" option package which included the steel-belted radial tires along with an upgraded suspension with Pliacell shock absorbers and front and rear sway bars. The RTS option was expanded for 1974 to all full-sized Pontiacs and radial-ply tires became standard on all 1975 models though an upgraded "RTS" package was still available as an option.
1975 saw the end of the pillarless 2-door hardtop model, replaced by a coupe with frameless door glass but with a thick "B" pillar and fixed rear "opera" window. The 1975 model year introduced rectangular headlights - its frontal appearance was similar to the Cadillac DeVilles and Fleetwoods of the same era.
With the demise of the Grand Ville series after 1975, Bonneville once again became the top-line full-sized Pontiac series, with a Bonneville Brougham model featuring the luxurious interior appointments from the departed Grand Ville.
Adjustable pedals were optional in 1976, the last year the Bonneville was offered as a pillarless 4-door hardtop; all subsequent Bonnevilles would have a thick B-pillar and metal-framed door glass.
Size comparison between 1974 and 1984 full-size Pontiac sedans
Sixth generation (1977–1981).
Bonneville would continue its flagship duties on the downsized big car line that was introduced for 1977. Bonnevilles (and Catalinas) were shorter in length, over four inches (102 mm) narrower and 800 pounds lighter compared to their 1976 counterparts, but had increased headroom, rear seat legroom and trunk space, and much-improved fuel economy – a major selling point in the years following the 1973-74 energy crisis.
Only a pillared four-door sedan and two-door coupe (with optional opera windows) were offered as the hardtop sedans and coupes offered in previous years were discontinued across the board at all GM divisions. The Bonneville also regained the Safari station wagon as part of its model lineup for the first time since 1970 with woodgrained exterior trim and interior appointments shared with Bonneville coupes and sedans. The Safari was available in both 6 and 9-passenger configurations and featured a dual-action tailgate that could be opened to the side as a door or downward as a tailgate, rather than the disappearing clamshell tailgates found in 1971-76 full-sized Pontiac wagons.
For 1980, all GM B-bodies received revised styling and aerodynamic improvements along with reduced weight.
The standard engine for Bonneville was Pontiac's new 301 cubic-inch V8 rated at and optional engines included a 170-horsepower 350 or 180-horsepower 400 cubic-inch V8. A 185-horsepower Oldsmobile 403 cubic inch V8 was also an option. In later years, increasingly stringent fuel-economy standards mandated by the Corporate Average Fuel Economy (CAFE) regulations would lead to the discontinuation of the larger engines with a 231 cubic-inch Buick V6 becoming the standard engine on Bonneville coupes and sedans for 1980 and 1981 with the only optional V8s offered including 265 and 301 cubic-inch Pontiac-built gasoline engines or an Oldsmobile-built 350 cid diesel powerplant.
The Bonneville and Catalina, already the smallest-selling of GM's B-body line, suffered a serious drop in demand following the economic recession that began in the spring of 1979. With that, GM decided to pull the plug at the end of the 1981 model year. Along with them went the 301 engine, marking the end of Pontiac V8s. From now on, the division would use Chevrolet engines.
Seventh generation (1982–1986).
The Bonneville nameplate didn't go anywhere following the discontinuation of full-sized Pontiacs and instead was simply swapped onto the midsized LeMans, which also suffered from poor sales, thus GM planners reasoned that attaching a more well-known model name to it would spark demand. This model had been produced since 1978 along with its siblings the Chevrolet Malibu, Oldsmobile Cutlass, and Buick Century, and sported a Buick 231 cid V6, Chevrolet 305 cid V8, or Oldsmobile 350 cid diesel V8. (A Buick 4.1 liter V6 was available in 1982.) The 1982-1986 models were officially known as the Pontiac Bonneville Model G (built on the GM "G" platform), although later models were not badged as such. Styling was revised to bear a closer resemblance to the departed B-body Bonneville and coupes were dropped. GM also began marketing the Bonneville in Canada for the first time starting in 1984 (1982 and 1983 Canadian models carried the Grand LeMans name), as GM's full-size Bonnevilles in Canada were referred to as .
While the previous LeMans, on which the new Bonneville was based, was classified as an A-Body, introduction of GM's new front wheel drive A-bodies (e.g. Pontiac 6000) in 1982 prompted the change to "Model G" on these RWD cars. 1983 was the last year for the G-body station wagon as the Pontiac 6000's wagon replaced it. The Bonneville sedan continued in base, Limited Edition (LE), and Brougham versions through 1986. The 1982-1986 Bonnevilles are direct descendants of the 1964 Pontiac Tempest. These 1982-1986 Bonnevilles were the smallest and the last of the old breed of Bonnevilles, having rear wheel drive, full perimeter frame (body on frame), and old-fashioned American car ride and styling.
Some Pontiac customers did not take to the "downsized" Bonneville as a portion of new-car buyers were switching their preferences from compact and mid-sized cars back to full-sized, V8-powered cars thanks to improving gasoline prices. Late in the 1983 model year, Pontiac reintroduced a full-sized car to the American market by bringing over the Canadian-built Pontiac Parisienne (which was essentially a restyled Chevrolet Caprice and powered by Chevrolet V6 or V8 engines). The Bonneville was then again one notch below the top of the line from late 1983 through 1986.
However, exactly as before, a downsizing proved its salvation. In 1987, the Parisienne was discontinued and the Bonneville was completely redesigned as a front-wheel drive car, rejoining its pre-1982 platform mates: the Buick LeSabre and Oldsmobile Delta 88 and it regained its status as the senior Pontiac. 
Eighth generation (1987–1991).
For 1987, Pontiac decided to change the car from the rear wheel drive G-body with the V8 to the more economical front wheel drive one-year-old H Body platform with the Buick LeSabre and Oldsmobile 88. Initially, a 3.8 L V6 was the sole engine, mated to a four-speed Hydramatic 4T60 automatic and performance was adequate from this pairing. The new Bonneville was placed on "Car & Driver's" “10 Best” list for 1987, offering both a base model and LE model. For LE models, an SSE sport package was also available that featured a quicker gear ratio, sportier suspension and more standard features, as the Bonneville was intended to have a more sporty, European flavor than the LeSabre and 88.
A host of trim level changes and a new engine became standard for the front wheel drive Bonneville's second year. First, for the 1988 model year, Pontiac replaced the LG3 with a revised version of the same engine platform, with an increase of 10 hp and 10 ft⋅lbf (14 N⋅m) of torque. This engine has the RPO code of LN3 and is the first time the Buick 3.8 is called the 3800 V6. Other models on the H-body platform were fitted with the updated engine one year later, in 1989. The LN3 was used through 1991, until the Bonneville was once again redesigned for the 1992 model year. It features sequential-port fuel injection, the LN3 produced and . Also new for 1988, the base model is dropped making LE the base model. Two new models are added, the midlevel SE (went from option package to trim) and line-topper SSE. The latter features an extra deep rear valence, a spoiler, lower body cladding, a digital compass/trip computer, an eight speaker premium sound system and much more. One notable feature of the SSE was the addition of automatic leveling rear air suspensions, which also included an inflator in the trunk. For 1989, a compact disc player became optional and in 1989 a remote keyless entry system was added to the options list for all 1990 models. A facelift was also introduced for the Bonneville in the 1990 model year, with revisions to the grille & headlights. Suspension revisions were introduced in 1990 for the 1991 model year. 
Pontiac also revised the trim levels for the remainder of this generation, removing the base trim (only used for 1987), keeping the LE went from being the top to the base trim, and adding the SE and SSE trims which were then available with many more comfort and convenience options standard such as, electronic climate control, a digital compass, Driver Information Center, 8-way (14-way for the SSE according to GM material) power leather seats, heated power mirrors, CD player with the premium sound package and many more. The SSE trim was exclusively equipped with an exterior sport appearance package that included body cladding, assorted ground effects, a body color grille and removal of the Bonneville door badges and Pontiac trunk badge, replacing the Bonneville trunk badge with an SSE Bonneville badge; in 1990 amber rear turn signals were added.
Ninth generation (1992–1999).
 
Unveiled on February 8, 1991, at the 1991 Chicago International Auto Show and launched in July 1991 for the 1992 model year, the interior and exterior of the car were completely redesigned. Developed over a -year period from 1986 to early 1991 under program director Dave Mitchell, styling work took place from 1987 to 1988, with a final design by John Folden being chosen in 1988 and frozen for production that same year. The first prototypes were built in 1989 and went into testing in mid-1989. In August 1990, production preparation began, with early production "builds" being constructed during late 1990. The first series production models were assembled in May 1991, with SE variants being launched in July 1991.
The trims were redone once again, the LE trim (which had standard six-passenger seating) was removed, the SE was now the base model (the only model to offer six-passenger seating as an option), the SSE was now the mid grade and a new top of the line trim was now added, the SSEi, which received a standard passenger-side airbag. According to GM's Pontiac division, these trim acronyms have no implied meaning.
The base and midlevel models were provided with GM's naturally-aspirated 3.8-liter V6, while the SSEi received the supercharged version. All engines came paired with a 4-speed overdrive automatic transmission. SSEi models got dual airbags and antilock brakes. SE and SSE models made due with a driver-side airbag and optional ABS. This generation hosted quite a few Bonneville firsts, becoming quicker and considerably safer. One of the most notable improvements over the previous generation was that the Bonneville SE now came standard with a driver airbag and was the first General Motors product equipped with a passenger airbag, while ABS was available as part of the sport appearance package. The SSE models came with standard ABS and traction control.
The new N/A 3800 Series I (RPO: L27) engine was used, producing and , as well as the newly designed force inducted Series I 3800 (RPO: L67) equipped with an Eaton M62 roots type supercharger which made and . The newly revised N/A L27, for the 1992 model year only, was not equipped with an EGR Valve, and can be distinguished by its white intake manifold, as opposed to black from 1993 and on.
Abridged safety options list:
For 1993, the Sport Luxury Edition (SLE RPO: H4U) was offered. This is essentially an SE sub-trim with more standard features such as leather seats, electronic climate control, automatic headlights, premium sound, and "crosslace" alloy wheels, though certain items such as electronic climate control and premium sound could be deleted from an SLE equipped car. This option package designation remained only on the RPO sticker until 1998, when SLE badges were added to the exterior of the vehicle. This continued onto the '99 model year. Many more standard options were available with the SSE. The SSEi came standard with most of the available options in the lower models, including the supercharged 3800 (RPO: L67).
For 1994, a new Generation III Eaton M62 supercharger came, along with new OBD-1.5 capabilities, raising the horsepower to , while torque was raised to . Also, this year introduced the new five-spoke "Torque Star" wheels. A resonator also became standard on the exhaust to lower the raspy tone that the engine produces. Passenger airbags also became standard on all models.
For 1995, the car retained the same appearance, but the SE and SSE trims received a new naturally aspirated engine, the Series II (RPO: L36). This engine made and . The SSEi remained equipped with the Series I SC 3800 (RPO: L67) engine until the 1996 model year, when it too was updated.
In March 2008, GM announced that these engines and other GM engines supplied with Dexcool antifreeze coolant might be prone to intake manifold failure and other problems with the cooling system if proper regular maintenance is not correctly performed. After settlement of a class-action lawsuit, GM agreed to compensate owners of many vehicles that suffered damage, regardless of negligence on the part of the consumer, if the consumer can prove damages.
1996–1999.
In September 1995, styling changes were introduced for the 1996 model year facelift. Some things were subtly reshaped, and other things, such as the tail lights, headlights, grille, and lower body cladding were drastically changed. The gap narrowed quite a bit regarding the exterior trim between packages. The previous generation showed an entirely different style of cladding and rear lighting for the SSE and SSEi, while this generation, at first glance, remains the same between the trims, with of course, the exception of the unique front bumper and grille. Also for 1996, the supercharged version of the 3800 Series II engine was introduced for the Bonneville. The SSEi and optionally the SSE got a new Eaton M90-supercharged L67, producing and . This engine was used from 1995 until it was retired from the Bonneville in 2003.
In 1997, Pontiac made a 40th Anniversary Edition to mark the 40th year of production of the Bonneville. Pontiac made six models: the SE, the 40th Anniversary SE, the SSE, the 40th Anniversary SSE, the SSEi, and the 40th Anniversary SSEi. The 40th Anniversary SSEi is the rarest model with a total production of 637 units. The 40th anniversary models all had a VIN with Y40. According to GM, all L67 equipped SE's are just SE's. But, it also means that in order to have this engine, they had to have RPO H4U: Sport Luxury Edition (SLE). But since this was not a model, it had no badging in 1995 (and supposedly not for 1996-1997), it was just an option for the SE. Since the L67 was not part of the SLE option, ordering an SE with H4U would get you the mini console in the headliner, the cobra head shifter, performance/normal shift selection buttons, leather interior, chrome delete side and bumper moldings, center shift console, and touring suspension—but no supercharger. But in order to get the supercharger in an SE, you had to also pay for the SLE option. The SLE optioned SE was supposed to compete with European sedans in appearance and performance, whereas the SSEi was to be more of an American muscle sedan. A new transmission, the 4T65-E was introduced in 1998 for the naturally aspirated 3800 installed in SE and SSE models, and the heavy-duty version, otherwise known as the 4T65E-HD was introduced in 1997 for the supercharged 3800 installed in the SSEi models.
Engine availability
Tenth generation (2000–2005).
The 2000 Bonneville was redesigned from the ground up with significant advancements in design, engineering and technology which Pontiac dubbed "luxury with attitude." The Bonneville was now built on GM's G platform,but GM chose to continue to refer to it as the H platform. Staying true to Pontiac's "Wide Track" heritage it had the widest overall track in its competitive class at 62.6 inches up front and in the rear. GM's StabiliTrak stability control system was introduced on the top-of-the-line supercharged SSEi model, later replaced by the GXP.
The Bonneville regained a V8 option on the GXP trim for 2004, its first since 1986, as a result of the discontinuation of the Oldsmobile Aurora. This opened up a "hole" in the GM lineup between Pontiac and Buick, allowing Pontiac to expand upmarket somewhat. The engine is Cadillac's Northstar V8, producing , and as Pontiac's website said, "With GXP, V8 power gets reintroduced into the Bonneville line in the form of the world-renowned 4.6 L (279 in³) Northstar V8 engine, giving in 6.5 seconds demonstrates better performance than BMW 330i and 530i, and Lexus ES. Its 3.7:1 final drive ratio is the most aggressive found on any car in its class."
NHTSA crash tests for the 2005 Pontiac Bonneville resulted in a safety rating of 4-stars for the Driver and 5-stars for the Front Passenger.
For the last year of production, Pontiac gave the mid-level SLE the new GXP styling. The 2005 SLE featured all GXP styling cues, except the wheels, badging, muffler tips and engine all remained unique to the GXP.
Discontinuation.
GM announced on February 8, 2005, that the Bonneville would be dropped from Pontiac's lineup for 2006. The last Bonneville left the assembly line on May 27, 2005. Only about 12,000 Bonnevilles were sold in 2005. With more than half of Pontiac dealers also selling Buick models, the Buick Lucerne along with the Chevrolet Impala continued as GM's only mainstream full-size cars until the introduction of the 2008 G8.