Rigs Got Bigger, Heavier, Nicer & Safer
Truckload carriers pushed for some changes, but others stemmed from geopolitics, economics & government regulations.
Tom Berg, Equipment Editor
With approval of the Motor Carrier Act of 1980, Congress unleashed the industry's potential, prompting a proliferation of new trucks.
Tractors and trailers grew in size and numbers, while rapid changes in truckload operations saw "plain vanilla" tractors replaced by fancier and much more comfortable equipment. Operators meanwhile demanded longer life for their vehicles, requiring truck and component makers to design and build longer-lasting equipment covered by extended warranties.
The most obvious development was the switch from cab-over-engine road tractors to the conventional-cab layout, and the use of bigger and heavier trailers. These were made possible by the federal Surface Transportation Assistance Act (STAA).
That law, passed in December of '82, waived state length limits on tractor-trailers if single trailers did not exceed 48 feet (longer in states where they were already legal) and doubles did not exceed 28.5 feet for each trailer. That meant tractors could be any length at all, and conventionals gradually displaced COEs as kings of the road. Meanwhile, the switch to 48s caused a busy trade in stretching existing trailers from 45 feet to 48.
STAA also made 80,000 pounds the federal weight standard for five-axle rigs, preempting lighter weight limits in some states - most notably "barrier" states in the Mississippi Valley, which had a 73,280-pound limit that prevented coast-to-coast travel by 80,000-pound rigs legal elsewhere. Allowable vehicle width went from 96 inches to 102.36 inches.
States that allowed longer, heavier combinations at the time of STAA were allowed to keep them - an element of legal "grandfathering" that's cited whenever some in the industry renew a call for even bigger combination vehicles. Grandfathering is why long doubles and triples operate in the West and on turnpikes in the East and Midwest. (It's also why trucks in Hawaii can be 108 inches wide).
Shorter limits remain in force on many state highways because the federal rules applied only to interstate and federal-aid highways and access roads within five miles of Network highways.
Grandfathering was also used as a wedge to open the door in many states to 53-foot single trailers. Some say shippers were behind this more than the industry, but the bottom line is, it was accomplished state-by-state. The overall argument made to reluctant legislators was greater productivity. This, along with trucking's superior service, helped push more railroad boxcar traffic into tractor-trailers and allowed many TL fleets to grow even faster.
Trouble was, what used to be a "truckload" - the amount of goods that fit in a 45- or 48-foot trailer - soon became what fit in a 53-footer. Rates seldom increased to compensate for the extra carriage, so shippers - and consumers - became the big winners as more freight traveled for less money.
As a result, some elements within trucking adamantly oppose any further size increases in trailers or long combinations - even the more widespread use of triples sought by less-than-truckload carriers.
Switch To Conventionals
Longer trailers are harder to maneuver, but companies nonetheless switched to conventional tractors to please drivers. Truck drivers liked conventionals for their smoother ride (wheelbases are generally longer and the driver sits behind instead of directly over the bouncing front axle).
They also liked the safety advantages (the hood and nose get to a frontal collision before the driver). And then there was the convenience (items in the sleeper didn't have to be battened down because the cab doesn't tilt for access to the engine, as is the case with COEs). Fleet managers also found that conventionals cost less to buy and maintain.
Even so, the switch to conventionals took more than a decade. Several major truckload fleets stayed with COEs well into the '90s because they are more maneuverable in tight loading-dock areas and city streets, especially in the East and Northeast. Thus a major advancement in COE design - the "flat floor" that replaced the traditional "doghouse" engine cover - occurred in the mid '90s.
Wheelbases also grew for most tractors, making them more stable and improving the ride, even for the few COEs still being built. Short, squat tractors, once common in the East and Midwest, became scarce. Meanwhile, federal noise limits forced truck and component makers to tone down their equipment to the point where many of today's tractors are as cushy quiet as limousines.
Fancy 'Long-and-Talls'
"Long and tall" tractors featuring long noses, big, high-roof sleepers, chromed stacks and fancy interiors also began appearing in truckload fleets in the '80s, and are now virtually standard in the TL segment. This type of tractor was formerly the domain of owner-operators and so-called premium fleets, whose owners and drivers prided themselves on running nice equipment.
A long-and-tall is usually a traditionally styled model - typically Peterbilt's 379, Kenworth's W900L and Freightliner's Classic - and they're also called "large cars." Some big fleets buy them to reward their top drivers. But aerodynamic models are also nicely outfitted with posh upholstery, dual stacks, bright-metal trim and other amenities to attract and retain good drivers.
The one-piece "integrated" cab-sleeper structure also became popular in the 1980s and remains so today. Extended cabs with space for a narrow sleeper bunk were first built in the 1920s and were offered into the '50s.
The old White Motor Co. revived the style about 1980, just before going bankrupt. Volvo White, which took over White's factory, products and nameplate, reintroduced it as the Integral Sleeper. It featured longer extensions and tall roofs with interior standup room.
Other OEMs followed suit and today nearly all offer integrated sleepers in their lineups. Some continue to sell separate sleeper boxes, which can be removed fairly easily to convert a long-haul tractor to a daycab. And of course aftermarket manufacturers still do a handsome trade in custom boxes.
Live-in accommodations are found in many long-haul tractors, whose drivers spend weeks and even months on the road with no company-owned terminals or bunkhouses in which to rest up. Such facilities disappeared by the '50s. Refrigerators, microwave ovens and TVs with video and CD players are now as common in sleepers as radios are in cabs.
Activities like cooking and watching TV put high loads on electrical systems, and generating power with tractors' engine-driven alternators - idling for short - is a long-time practice that increasingly conflicts with anti-idling ordinances in various locales. Battery inverters, auxiliary power units, sleeper heaters and coolers and other equipment continue to be developed and marketed.
Fuel and Emissions
Significant improvements in fuel economy occurred during this time period, but probably would have happened anyway because they were influenced by geopolitics, economics and government regulation. The first Arab Oil embargo was in autumn of 1973, seven years before deregulation and nine years ahead of the STAA. The embargo brought sharply higher fuel prices and the national 55-mph speed limit - the despised "double nickel." It also jolted some operators of highway tractors into installing aerodynamic aids, primarily roof-mounted air deflectors.
The '79 embargo pushed builders into streamlining entire tractor and truck models, and scared many operators into buying them. A few pioneers developed effective aero aids for trailers, but they didn't catch on with most owners and still haven't. Engine builders developed low-speed models - some governed as slow as 1,600 rpm - to reduce fuel usage.
Electronic engine controls, first introduced by Detroit Diesel in the mid-'80s, also helped squeeze fuel, both with combustion efficiency and easy implementing of the gear-fast, run-slow concept (something very difficult to accomplish with axle gearing). Today, electronic control modules can be reset to alter horsepower and torque - usually to raise them to give the truck higher resale appeal.
But electronic controls' primary job was and is to reduce exhaust emissions to comply with increasingly tight limits decreed by federal and state governments. Until recently, engine manufacturers were able to make their diesels burn ever cleaner and still deliver better fuel economy. Many engines lived longer, as well.
But the latest limits - in October 2002 for some builders' diesels and January '04 for the rest - have been costly on fuel and added thousands to the price of a typical truck. New rules for '07 and '10 will continue this trend.
Electronics Everywhere
Truck builders avidly adopted advanced electrical and electronic systems everywhere in their chassis. Electronics brought new capabilities like quick diagnostics and remote vehicle tracking, and new products like effective anti-lock brakes and slick-shifting automatic and automated transmissions. On-board electronic systems can also tie into computer-based information technology networks - what was once called "data processing" - in companies' offices.
And what the truck and driver are doing can be remotely viewed and even altered by managers from their desktop PCs. This has advocates for drivers and personal privacy upset, and they often invoke the specter of George Orwell's "Big Brother" in arguing against it. On-board recorders can keep track of drivers' hours of service habits, but should they, especially when authorities could use the data to issue tickets?
Meanwhile, maintenance managers and mechanics were stumped when faced with strange, "wired" equipment in their shops. The learning curve for electronics was steep and painful, and it exacerbated the chronic shortage of mechanics, who meanwhile were becoming "technicians" to cope with this new world.
Then again, some progressive managers are promoting the PC tie-in to lure young, computer-savvy people into truck maintenance. Yet like deer caught in oncoming headlights - which themselves have become more complex and costly - many fleet executives remain almost dazzled by vehicle electronics and seem unable to resist their spread.
Down on the pavement, advanced radial tires with low rolling resistance also came in the '80s and '90s, and tire makers touted their fuel economy benefits. However, the tires' main gains were in tread life for good initial mileage, and strong casings that allow economical recapping. Manufacturers of retreading supplies and equipment meanwhile pushed their products to where the million-mile tire is within reach, if not already grasped.
Meanwhile, tire makers continue to experiment with electronic ID chips, and more fleet managers are popping for tire pressure monitors and systems that automatically inflate (and sometimes deflate) tires as needed.
Vertical Integration
With the notable exception of Mack Trucks - and unlike their counterparts in Europe and Asia - North American heavy truck builders have been "assemblers" of vendor-made parts and components for much of their histories. All along, they put more and more proprietary parts in their cabs and frames, and since the late 1980s OEMs have been evolving toward vertical integration.
They began by paring their options lists so they can deal with fewer vendors, leading to "preferred supplier" arrangements. This helps OEMs stay financially healthy and weather losses during recessions, and helps to limit truck price increases. However, this has also reduced specifications choices that maintenance managers traditionally prized.
Affected were everything from engines, transmissions and axles to alternators and air dryers. Sometimes the options paring was done all across the board or by pre-spec'ing vehicles for certain applications, with deals sweetened by lowered prices, quick deliveries and longer warranties.
Either way, product planners tended to keep popular components and eliminate odd-ball parts.
Consolidations & Improvements
For the most part, equipment developments have been on a steady course that began way before deregulation and the STAA. From their starts in the early 20th century, truck builders prided themselves on engineering advancements, even as many floundered and failed during economic hard times. Like other companies in other industries, some firms simply went down and others were absorbed by competitors.
Countless names and nameplates have disappeared, but the traditions of product improvement have continued. Those of us who drove trucks 40 and 50 years ago marvel at the comfort and ability of today's models, even as we pine for vehicles that were easier to understand and fix. And we know that "old iron" would never stand up to today's operations. Here are more examples of equipment changes and improvements:
Tandem-axle tractors - Many truckload carriers in the East used single-rear-axle tractors to pull 40- and 42-foot semitrailers. But the switch to longer trailers brought higher payloads that had to be distributed over an extra axle. Though tri-axle semitrailers might have done the job, our federal bridge-formula weight law favors two widely spaced tandems, and it's still what's used here on most tractor-trailers.
Easy shifting transmissions - Advances in gear cutting, the addition of low-inertia shafts and electronic aids made manual transmissions quieter and easier to shift. Electronics improved the performance of hydraulic automatics and brought about automated mechanical transmissions - which, compared to non-synchronized manuals, are no work at all to operate. A few fleets have embraced AMTs in order to hire inexperienced workers, including women and ex-military drivers accustomed to automatics.
Soft-riding suspensions - Steel-spring suspensions were standard until drivers began demanding smoother riding air bags. So carriers bought them, first on tractors and then on van and reefer trailers, because studies showed that cargo, too, benefited from protection against rough pavement. Air suspensions effectively equalize weight between axle pairs, and are popular on flatbeds with spread tandems. And they protect vehicles themselves from being shaken apart. Helping, too, are more compliant parabolic leaf-spring suspensions on steer axles, and advanced mechanical suspensions on vocationally oriented tandems.
Air-sprung cabs - Cab supports incorporating air bags to filter out vibration and "back slap" were pioneered by Ford and Mack. But it became popular as an aftermarket accessory invented by an owner-operator. Kenworth offered the product on its K100 cabovers, and other designs are now standard or optional from all builders on many trucks and tractors.
Setback front axles - Though axle-forward designs are still used on some models, the setback axle became popular on highway tractors in the mid-'80s because it shoulders more payload weight and allows a tighter turning circle. Relaxation of length limits encouraged the SBA because it allowed designers to lengthen wheelbases and more easily adjust axle positions.
Power steering - "Armstrong" manual steering was another industry standard that disappeared as higher weights on front axles required mechanical help for drivers. Virtually all on- and on/off-road trucks now come with hydraulic power steering, and few drivers today ever twisted a wheel with manual steering gear.
Air conditioning - Almost unheard of in commercial trucks until the Teamsters union made A/C a contract issue many years ago, it's now virtually standard on all highway trucks.
Better brakes - Federal Motor Carrier Safety Standard 121 in 1975 introduced stopping-distance limits that required brakes on front wheels (many tractors didn't have them) and anti-lock braking systems. Both caused problems, but ABS was especially troublesome and it took a court suit by Paccar Inc. to force the feds to back off. Modern ABS, mandated in the mid-1990s, is more reliable and beneficial, most fleet managers acknowledge.
Engine retarders - Once an expensive option bought mostly by owner-operators, retarders moved big-time into fleet trucks when Cummins came out with its low-cost C Brake - essentially an older-design Jake Brake whose patent had expired. Jacobs had to lower its prices, and meanwhile Pac Brake and others got into the business. So competition accomplished what federal authorities had considered mandating, and now heavy rigs can safely descend long grades at highly productive speeds with little wear on service brakes.
Brighter lights - Lamps made with cool, light-emitting diodes (LEDs) use 10% of the current and last 10 times as long as traditional incandescent marker, tail and turn lamps. Grote was the first to market a red LED - winning the Truck Writers of North America's first Technical Achievement Award in 1991. Since then, Grote and competitors like Truck-Lite have developed amber and white LEDs. Ten years earlier, bright halogen headlights began eliminating the use of auxiliary fog- and driving lights by many truckers. Complex-reflector headlamps are now the rage because they are more capable and stylish.
Reflective markings - Economically the brightest idea of all - red-and-white tape and reflectors applied to tractors and the rear and sides of trailers - make rigs really stand out at night. The industry fought this development, too, especially when the government asked for an unrealistic deadline and wide-spread installation of the reflective materials.
And one now-retired fleet manager even argued that drunk and drugged drivers would swarm to the reflective markings like moths to a flame. But a government-sponsored test in the early '90s proved them statistically effective in reducing rear-end collisions.
Best yet, they "run" on somebody else's lights.
But most of these developments were costly, yet came in spite of the industry's financial struggles. Deregulation forced the industry to become more efficient while wringing out most profits.
Still, builders somehow continue to find the necessary R&D money, and their customers came up with the bucks to buy the trucks.
Thanks For The Memories
These people scoured their memories and passed along historical knowledge that contributed greatly to this article: Larry Strawhorn, retired engineering vice president of the American Trucking Assns.; Robert Braswell, technical director of the ATA's Technology & Maintenance Council; Todd Spencer, executive vice president of the Owner Operator Independent Drivers Assn.; and Jim Winsor, HDT's executive editor. Thank you, gentlemen!
