Naming any car the very best one in the whole world is an exercise fraught with peril. In some contexts car "A" is perfect while car "B" is ludicrously inadequate, and in other situations it's exactly the opposite. The fastest cars usually can't carry your family to Disney World and minivans aren't likely to win many races. But virtually every esteemed commentator, media organization or drunken bar patron who's ever dared name one vehicle the best the planet has to offer has had BMW's 5 Series on the short list for consideration.
The 5 Series has, in its structure, form, performance and overall excellence, been the archetypical sport sedan for more than 30 years. It's the bogey against which every other sport sedan must be measured and the car that pushed BMW beyond the niche it secured with the much smaller 1600, 2002 and 3 Series. And every time BMW redesigns the 5 Series, it risks destroying all that.
Before the 5
In many ways the 5 Series development parallels that of the 3 Series with both tracing their heritage to the "Neue Klasse" (New Class) midsize car that went on sale in the U.S. in 1962 as the 1500 four-door sedan. The New Class was the first modern BMW. It had state-of-the-art features like a unibody structure, MacPherson strut front and independent rear suspension and an 80-horsepower, SOHC 1.5-liter four in its nose. The wildly popular New Class did nothing less than save BMW.
Evolution of the New Class split, however, with the introduction of the 1600-2 two-door model in 1966. With a two-inch-shorter wheelbase, two fewer doors and less weight than other New Class models, the two-door model performed better even if it was slightly compromised in utility. When the two-door's engine grew to two liters in displacement during 1968, the model's name became "2002" and that evolutionary branch would eventually lead to the 3 Series.
Meanwhile the four-door New Class sedans continued in production with their four-cylinder engines also growing eventually to 2.0 liters and 100 hp in 1966's 2000 sedan. Then in 1968 BMW introduced their large sedan, powered by a new range of inline six-cylinder engines and sold as the 2500 when equipped with a 2.5-liter version of the six and the 2800 with a 2.8-liter displacement.
By the early 1970s, the New Class cars were obviously aging and the two-door 2002 was an established hit. It was time to replace the New Class four-doors, and BMW decided to make the replacement significantly larger than the 2002 to distinguish it in the marketplace and open a new niche for BMW. The trick would be doing that while not impinging on the niche established by the E21.
That successor would be the 5 Series.
First Generation (1972-1981): The E12
The first 5 Series wasn't really much smaller than the "big" E21 model sold alongside it. With a 103.8-inch wheelbase and 181.9-inch overall length, the 1972 520 was a significant 4.7 inches longer than the 2000 sedan it replaced (and only 3.1 inches less lengthy than the European-model 3.0S version of their large sedan). Considering that the only engine offered in the 5 Series during that first year of production, a 2.0-liter four making 115 hp breathing through a carburetor in the 520 or 125 hp when ingesting atmosphere through a fuel-injection system in the 520i, the first 5 was underpowered. And, wisely, BMW concluded it wasn't an appropriate vehicle to market in America in that form.
The basic elements of the first 5 Series weren't exotic. As in the New Class, the front suspension was a pair of simple MacPherson struts while the independent rear was supported by a set of semi-trailing arms. The unibody structure was impressively taut, the four-wheel disc brakes were effective and it was probably the quietest and most refined BMW that had yet been built.
But the first 5 Series still carried with it a slew of innovations for BMW. For starters, it was the first vehicle to use the present-day naming scheme (series number followed by two numbers indicating engine displacement). Second, it was the first BMW designed to accommodate any of the company's four- or six-cylinder engines (the first six-cylinder 5, the 2.5-liter 525, appeared in Europe for the 1973 model year). Third, it was a simpler and cheaper car to build than other BMWs, and that made it tremendously profitable. Fourth, despite its economical construction, it was a leap forward in refinement and sophistication. And fifth, it was a much more contemporary design than previous BMW sedans, which was an enormous help in shedding the company's heretofore dowdy image through the '70s.
BMW finally brought the 5 Series to America for the 1975 model year when the 3.0Si's SOHC, 3.0-liter, straight six was installed to produce the 530i. The 530i was designed for America, and the big engine was particularly needed over here because of the then-new emissions regulations that were strangling engine outputs (the '75 model year was the first in which most new cars were equipped with catalytic converters though the 530i itself managed to get by without one). By mid-1970s standards, the 530i's 176 hp was startling for a 3.0-liter engine that same year the Cadillac Eldorado's 8.2-liter V8 was rated at just 190 hp and the most powerful 5.7-liter V8 offered in the Chevrolet Camaro made just 155 horses.
Beyond its exemplary output, the 530i's six was silken and delivered its torque in an elegant, unbroken ribbon, and the Getrag four-speed manual transmission behind it was nearly as sweet (the optional three-speed automatic wasn't so enchanting). With so many other new cars then out there gagging on their emissions gear, wallowing on Conestoga-era suspension and wearing garish vinyl roofs and opera windows, the 530i was a paragon of performance, composure and good taste. Road & Track spurred one 530i to 60 mph in 10.2 seconds and Motor Trend measured one doing the same trick in 9.7 seconds. That's performance pretty close to the European market's 528 model that used a 2.8-liter version of the straight six but didn't carry America's oversize bumpers and emissions equipment. It was all enough to make the car's $9,097 base price seem absolutely reasonable.
The 530i was an instant hit, and consequently, BMW didn't mess with it for 1976. A slight restyling came with the 1977 model year that made the front grille's distinctive twin kidney center taller and more prominent leading to a new narrow raised center along the hood. The taillights were also redesigned and made larger. Those changes were enough to carry the car through 1978 as well.
BMW brought the 2.8-liter inline six over to America's 5 Series as a replacement for the 3.0-liter to create the 1979 528i for the American market. While BMW rated the 2.8-liter motor at 169 hp, the use of a catalytic converter, other new emissions technologies and a new five-speed manual transmission actually improved drivability, fuel economy and performance. Road & Track even got one 528i to 60 mph in just 8.2 seconds.
Though it never came to the United States, BMW produced one of the most significant 5 Series models ever during '79. The M535i was the first product of the BMW Motorsport division to reach consumers and featured a large-bore/short-stroke version of straight six displacing 3.5 liters and making 218 hp. Available only in Europe and only backed by a close-coupled five-speed manual transmission, the M535i was the prototype for all the glorious M cars to follow M1, M3, M5 and M6. It's also easily the most desirable of all the original E12 5 Series cars.
There were few changes to the 1980 528i and even fewer for 1981. But it was time for the 5 to evolve.
Second Generation (1982-1988): The E28
Following a car as successful as the first 5 Series is always daunting, so it's understandable why BMW's first redesign of the car was very conservative. To many it was even tough to tell much difference between the new E28 5 Series and the old E12. The E28's windshield, roof and doors, for example, either carried over directly from the E12 or were only lightly modified. The most obvious change was to the car's rear third where the fenders and trunk lid stood high rather than drooping as in the E12. But the nose was also thoroughly changed with a new hood that didn't wrap over into the fenders (as it did on the E12) and a more aerodynamic grille.
Though the redesign was strictly evolutionary on the outside, there were substantial changes beneath the E28's skin. The use of new materials and advanced construction techniques dropped somewhere between 132 and 200 pounds (depending on the model). The inside of the car was redesigned to be more ergonomically efficient and safer by reducing the number of protruding bits and increasing the use of padding. Finally, there were new electronic systems like a service interval indicator and an optional antilock braking system.
The E28's suspension was an evolutionary step forward from the E12. The front struts now incorporated a double pivot universal joint and angled coil springs. The rear suspension used a transverse link with much better geometry than before. And the car's 103.3-inch wheelbase was a half-inch shorter than the E12's.
But the biggest change for American-bound E28s was the new 2.7-liter "eta" engine. Installed in the new 528e (BMW wasn't going to lose sales just to accurately reflect the drop in displacement in the car's name) that replaced the 528i, the eta inline-six was pretty much a miserable lump of metal. The high-compression eta had a low redline in order to ensure good fuel economy not good fun. In fact, it was no fun at all. Rated at just 121 hp, it was an engine seriously strained by the 5 Series' 2,960 pounds of bulk and transmission gearing aimed at eking extra distance from every drop of gas. The 528e was the only E28 sold in America initially so it was tough to appreciate the new car's improved chassis with such compromised power production. The lousy eta engine was backed by either a sweet five-speed manual or a three-speed automatic transmission.
Virtually no changes were made to the 528e for 1983, but a new 533i sedan powered by a 3.2-liter version of the six-cylinder engine was now available offering a strong 181 hp. Besides a greatly appreciated increase in power, the 533i offered a tauter suspension, rode on Michelin TRX tires mounted on wheels with an unusual 390-millimeter diameter and came standard with antilock brakes.
A four-speed automatic transmission was added to the options list for both the 528e and 533i in 1984, but other changes were scant. However, in Europe the first of the mighty M5s went on sale. Equipped with the DOHC, 24-valve, 3.5-liter Motorsports version of the BMW straight six, the M5 was an instant legend. And with a full 286 hp available, it was quick enough to even outrun that legend. But it wouldn't make it to America until four years later.
The 1985 model year brought with it a third 5 Series model for the American market and the biggest engine yet offered here. The big engine was a new 3.4-liter, 182-hp version of the SOHC six installed in the 535i, which replaced the 533i. The new model was the 524td, which put a 2.4-liter, turbocharged, diesel inline six under the 5's hood. Saddled with a mandatory four-speed automatic transmission and getting just 114 hp from its oil-burning power plant, the 524td was easily the slowest BMW 5 Series yet. BMW also sold some of the same turbodiesel sixes to Ford for installation in the Lincoln Mark VII and Continental.
Antilock brakes became standard equipment on the 528e and 524td for 1986, but other changes were few. The diesel 5 Series vanished before the beginning of the 1987 model year, but a new 535iS model appeared at the top of the range wearing a front air dam and rear spoiler. No more powerful than the 535i, the 535iS wasn't quite intimidating. But it paved the way for the intimidation that was to follow.
There were practically no changes to the 528e, 535i or 535iS for 1988 and really, who cared? The big news was that the M5 finally made it to America that year with so much performance it blew right past everyone's expectations of what a sport sedan could be. But it wasn't quite the full-throated, 315-hp beast then being sold in Europe under the same name. American emissions requirement sucked the 3.5-liter, DOHC, 24-valve six's output down to 256 hp. But for wealthy, performance-starved Americans, any taste of M5 goodness was greatly appreciated.
By the late 1980s, the E28 was looking distinctly old-fashioned. It was time for the 5 Series to take a big step forward.
Third Generation (1989-1996): The E34
The third-generation 5 Series, designated E34 within BMW, was truly an all-new vehicle. The 1989 5 rode on a longer 108.7-inch wheelbase, had an all-new structure with an all-new suspension, was significantly roomier than before and was a leap forward in sophistication, refinement, performance and overall comfort. As good as the E12 and E28 5 Series cars were, it was the E34 that propelled the line to the forefront of critics' minds. This is the machine that people took seriously as a contender for the title "World's Best Car."
Much of the E34's structure and components were proved first on the new 7 Series large sedan introduced for the '88 model year. That included the revised MacPherson strut front suspension and the all-new independent multilink rear suspension. Most impressive about all this was how the new E34 took the solidity and poise of the 7 Series and translated down to a more manageable size while simultaneously increasing agility. The E34 featured all the impregnable qualities of the 7 combined with the cut-and-thrust athleticism of the 3 Series. It was in every way impressive.
It was also good-looking. Braking from the slab-sided tradition of its ancestors, the E34's flanks were gently curved and quite aerodynamic with a drag coefficient between 0.30 and 0.32 cd (depending on the model). There was some hint of previous 5s in the shape of the new car's side windows, but otherwise this car was aggressively new.
All new as it was, the E34 arrived in America powered by slight variations of familiar drivetrains. The 525i used a 2.5-liter version of BMW's small SOHC straight six making 168 hp, while the 535i used a 3.5-liter version of the big SOHC six rated at 204 hp. While Europe got a new E34-based M5, it wasn't initially offered in America.
A driver-side airbag became standard on all 1990 BMWs, but otherwise changes to the 5 Series were minimal. Automatic Stability Control (ASC) was added to the 535i's options list during the year, however.
The M5 returned to America during the 1991 model year with its 3.6-liter, DOHC, 24-valve Motorsport six now whacking out a full 310 hp. Available only with a five-speed manual transmission, the M5 was again a sensation despite the fact that it wore a set of the ugliest 17-inch wheels ever made.
A second cam and another 12 valves were added to the 525i's 2.5-liter six for 1992, which raised its output to 189 hp. Buyers could also finally get a 5 Series station wagon during 1992 with the introduction of the 525i Touring. However, while Europe could get 535i and eventually M5 versions of the wagon, Americans were restricted to the modest 525i.
The M5 finally got some attractive wheels for 1993 and new aerodynamically styled side mirrors to go with them. But the 5 Series status quo was otherwise maintained.
A pair of engines debuted for 1994. In a stunning development, the 535i was replaced during the 1993 model year with a new 530i model powered by a new 3.0-liter, DOHC, 32-valve V8. Additionally, BMW offered a new 540i powered by a 4.0-liter version of the same bent engine. The new 530i had 215 hp available to it and was available in both the sedan and Touring wagon. The 540i's V8 knocked out an impressive 282 hp and attracted some buyers who might have otherwise considered an M5 though the 540i was originally available only with a new five-speed automatic transmission. In fact, the M5 was, once again, gone from the lineup.
All 5 Series got revised front fascias for 1995, and the 540i was now available matched to a six-speed manual transmission and a lowered, Motorsport-tuned suspension with 17-inch wheels and tires. Was it a good substitute for the missing M5? It wasn't bad at all.
Technically, there were no 1996 5 Series cars offered in America, as sales of the 1995 models continued into May of 1996. Obviously, there was another new 5 on the way.
Fourth Generation (1997-2003): The E39
Much as the E28 evolved from the E12, BMW's new E39 5 Series was a refined expression of the ideas embodied by the E34. Slightly larger in virtually every dimension and riding on a 111.4-inch wheelbase, the greatest innovation of the new 5 Series lay in its suspension where most of the links and elements were now cast of lightweight alloys instead of steel. Combine that dramatic reduction in unsprung weight with the adoption of rack-and-pinion steering and the result was a more responsive chassis than ever before.
In Europe there were no longer any four-cylinder 5 Series cars offered, while in America the 5 Series offerings dwindled to just the six-cylinder 528i and the V8-powered 540i sedan for 1997. With 190 hp on tap and five gears aboard either its manual or automatic transmissions, the 528i was a solid performing machine despite its position as the entry-level 5. The 540i, on the other hand, now had a full 282 hp that was lashed either to five-speed automatic or six-speed manual transmissions after a displacement bump to 4.4 liters (a change not reflected in the car's name). The six-speed included a "Sport" package of an aggressive suspension and oversize wheels and tires to produce something nearly M5ish in nature.
Side curtain airbags became standard equipment on all 1998 5s, and the sport suspension and wheels were offered on the automatic-equipped 540i, but otherwise the E39s appeared to carry over from their inaugural season. The station wagon (now called "Sport Wagons") returned to the lineup for 1999 in both 528i and 540i forms. Also new that year on the 528i was an aluminum cylinder block and a variable timing system that increased output to 193 hp. The 540i's V8 also got variable valve timing, though output remained unchanged at 282 hp.
Back with a vengeance for 2000 was the M5 now powered by a new Motorsport version of the V8 displacing 5.0 liters and stroking out a thrilling 394 hp. Available only with a six-speed manual transmission, the new M5 was simply the quickest production four-door sedan in BMW's or any other manufacturer's history up to that time. Crouching on 18-inch wheels with a deep front air dam, the M5 had sinister looks to go with its aggressive personality and towering performance. The latest M5 was as luxurious as a Cadillac, as quick as a C5 Corvette and as agile as a 3 Series sedan. The other 5s went through the year unchanged.
For 2001, the 528i grew into a 530i with a new 3.0-liter version of the six now making 225 hp. A new 525i, with a 2.5-liter version of the six now rated at 184 hp, also joined the lineup. The 525i, 530i and 540i were all available as either a sedan or wagon. The M5 was still available only as a sedan.
Minor changes occurred for 2002, among them more standard equipment for the 525i (including a CD player and power seats) and an increase in output for the 540's V8, which now made 290 hp.
The last year of this highly respected generation of 5s would be 2003. Among the minor changes was a new sport package for the 540i (standard on the manual-shift sedan, optional on other 540s) with 18-inch wheels, a revised sport suspension and various cosmetic upgrades. Also, BMW's outdated CD-based navigation system was replaced by a DVD-based system. Otherwise, this family of top-shelf sedans and wagons stood pat as BMW prepared another all-new 5 Series for 2004. Could the German carmaker possibly top itself again?
Fifth Generation (2004-Present): The E60
The all-new 5 Series 2004 is an all-new car that demands attention not just for its mechanical competence but also for some of its adoption of controversial technology and radical new looks.
"In terms of overall philosophy," wrote our editor in chief, "the largest shift from the previous model comes in the form of technology. Several items are pulled directly from the recently redesigned 7 Series, including iDrive, Active Roll Stabilization (ARS), Active Cruise Control (ACC), Park Distance Control (PDC) and a Harmon Kardon Logic7 sound system though only iDrive is standard on all 5 Series models." But the most intriguing new technology was "Active Front Steering" (AFS), an exclusive to the 5 Series which varies the steering ratio all the way between 10-to-1 and 20-to-1, depending on vehicle speed.
Again the new 5 Series has grown over its ancestors. Now riding on a 113.7-inch wheelbase and stretching out 190.6 inches in overall length, the new 5 Series is easily the roomiest 5 yet. But yet again, BMW has managed that swelling in size so well that it hardly affects the driving experience at all; this car is just as agile as any previous 5.
The basic lineup of the new 5 Series is unchanged from before, though the wagons won't be along until the 2005 model year. There's still a 525i and 530i with BMW's familiar straight sixes aboard, and the new 545i uses the same 4.4-liter engine as the 540i did, but recognizes the displacement in its name and then some. The 2.5-liter six is still rated at 184 hp, the 3.0-liter six makes 225 horses and the revised 4.4-liter V8 now makes a stunning 325 hp. New six-speed manual and automatic transmissions are offered with each engine with manual "Steptronic" shifting on the automatic and the exotic "Sequential Manual Gearbox" (SMG) available with the manual transmission.
Early in its life the E60 5 Series has earned raves for its performance and some derision for its flamboyant styling and frustrating iDrive control system. Only time and the imminent appearance of a V10-powered, 500-hp M5 will tell if this 5 earns a place alongside its progenitors in the pantheon of great BMWs.