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Whether she a professional driver with years of experience, or wouldn’t know a Peterbilt native a Packard, there’s no denying that the 18 wheeler is an outstanding machine.

They come in all shapes and also sizes, and also haul whatever from new produce and steel, come cars, cattle, and gasoline.

They’re ever-present symbols on America’s highways, and also without castle the nation’s economic situation would grind to a screeching halt.

For those who’ve never eased a heavy Freightliner under a mountain pass or backed a Kenworth under a invited trailer, fine cover the basics first.

18 Wheeler Truck Facts

Though the the smallest tractor trailers have just 10 and also the biggest dozens more, most large rigs have 18 wheels.

Big rigs cargo capacities can more than 40,000 pounds, and also gross weights up to 80,000 pounds. They require all those wheels and tires to spread that bulk over the largest feasible area.

Standard tractor trailers are generally 13½ feet high, around 70 feet long, and have five axles. However those that haul oversized tons may be lot higher, longer, and also heavier.

Decades back when fuel was cheap and regulation spotty, truckers typically roared under the highway much quicker than they carry out today.

Now many semi van have tools on your engines the limit speed. For fleets lock typically collection between 62 and also 68 miles every hour for safety and also economy. Because that owner-operators the speed limiters may be set much higher, or turned off altogether.

At 100,000 miles every year, the difference in between 6 and also 7 miles every gallon deserve to equate come a to save of nearly $7,000.

Compared to family members cars, trucks have actually huge transforming radiuses. They need between 40 and 50% more distance to involved a finish stop. Castle can’t stop on a dime.


Semi van Engines

We’ve currently established that 18 wheelers space massive, powerful, and also worthy of our respect. However it’s the part couple of ever gain to view that does many of the hefty lifting.

Day and night, rain or shine, diesel engines toil far in your dark compartments subject to extreme conditions that would certainly turn average gasoline engines into a smoldering hunks that plastic and aluminum.

Their strength output counts on your size, application and also the vehicle’s gross auto weight rating (GVWR).

But generally engines in Class-8 trucks:

have displacements in between 12 and 15 literscrank out 400 to 500 horsepowergenerate 1,200 come 2,000 pound-feet of torque

To put things into perspective, auto engines usually:

have displacements between 3 and 5 litersproduce 150-250 horsepowergenerate 200 come 300 pound-feet of torque

Unlike automobile engines that seldom hit the 200,000 mile mark, it’s typical for over-the-road diesels to last 1 million mile or more. They deserve to be rebuilt many times to expand their organization lives also further.

Semis deserve to have one tank or two, organize 300 gallons or much more of diesel fuel. They are qualified of traveling practically 1,500 miles between fill ups.

The most common diesel engines are manufactured by Detroit Diesel, Cummins, Volvo, Mack, Navistar International and also Paccar.

For year Caterpillar engines were among the most popular, but CAT no longer manufactures heavy-duty truck engines for on-highway use.

Related > The finest Truck Engines + The Worst


Truck Transmissions, and How to usage them choose a Pro

Most fleet trucks have 9 or 10 forward gears. Though they’re couple of and far in between these days, car with manual transmissions usually have only 5.

Owner-operators and heavy haulers typically spec their rides v bigger transmissions like 13 and also 18 speeds.

They’re often necessary when transporting hefty loads in mountainous terrain.

Though fighting that many gears may seem choose a complicated task, in the ideal hands they have the right to make driving easier and also more lucrative by reduce the number of shifts and also increasing fuel economy.

Interested in learning how to shift an 18-speed? examine how the pros perform it!

Traditionally, nearly all tractor-trailers were fitted with hand-operated transmissions.

But in the never-ending quest to save fuel and accommodate inexperienced drivers, countless fleets have actually switched come automatics.

Old-school truckers and owner operators have tendency to shun them prefer they perform low-calorie sugar substitutes and decaffeinated coffee.

They’re perceived as much less responsive, much more dangerous when driving ~ above snow and ice, and also just plain boring.

But data shows that when driven correctly they use much less fuel, for this reason they’re definitely here come stay.


18 Wheeler tools

Fifth Wheels and Kingpins

Fifth wheels room the large u-shaped slabs of stole bolted to the tractor’s framework behind the cab.

Kingpins are the arm-sized steel pins the protrude from under the former of trailers.

When the tractor is backed under the trailer the kingpin slides into the 5th wheel. As soon as done correctly, it’s soon locked into place by powerful jaws.

But be warned, if those jaws nothing grab that kingpin prefer they’re claimed to, you may be in because that the shortest pilgrimage in the history of trucking.

Related > how to on slide the fifth Wheel



Nearly anyone is acquainted with axles, yet tractor-trailers have actually steer axles, drive axles, and trailer axles.

Though steer and trailer axles space pretty self-explanatory, the the drive axles at the back of the tractor the are connected to the engine via the driveshaft.

These axles take all that power from the diesel and also use it to propel the truck forward and also backward. Part tractors have actually one drive axle, but most have two.

Fairings and Skirts

These days most trucks have actually fairings and skirts.

Sometimes they’re only on the tractor, however they’re becoming more common ~ above trailers too.

Their tasks are to improve aerodynamics and also increase fuel effectiveness thereby to decrease the vehicle’s operation costs.

Tractors have had actually fairings on your roofs, over your fuel tanks, and behind their cabs because that decades, but trailer skirts are fairly new.

They’re lengthy thin sections of metal, fiberglass or plastic slung under the trailer, and also they aid trucks slide v the air with less resistance.


Trucking Terms precious Knowing

From bobtails and also day cabs, to doubles and reefers, the trucking terms and phrases supplied by truckers referring to 18 wheeler trucks, deserve to be downright confounding.

But thankfully, many of them aren’t difficult to learn.

Here space a couple of easy examples:

if she driving a tractor without a trailer you bobtailingif you’re pulling a trailer equipped v a temperature controlled unit it’s referred to as a reeferstandard trailers supplied for hauling general freight are called dry vansday cabs space tractors without sleeperstrucks through sleepers are called over-the-road tractors or sleeper trucksdoubles refers come a tractor pulling much more than one trailerB-Trains are double trailer configuration that may be nearly 90 feet long

Now stop look in ~ a couple of that require more explanation:

Double Clutching

In car that have actually manual transmissions, once the driver depresses the clutch it enables the change lever come slip easily into the following gear.

That’s because their transmissions are synchronized, however on 18 wheelers, transmissions are unsynchronized.

To get around this, commercial chauffeurs must usage a an approach called double clutching as soon as working their method through the gears.

Double clutching entails briefly place the transmission in neutral before moving on come the next higher gear.

The process is similar when downshifting.

But in this circumstances the driver will additionally need to tap the accelerator to obtain the engine RPMs into the sweet spot prior to the transmission will perform what he wants it to.


For twin-screw or tandem journey tractors, (those with two journey axles) wheelbase is calculation by measuring the distance between the facility of the steer axle’s hub and the point between the two drive axle hubs.

On a single axle tractor, the measurement is indigenous the facility of the steer-axle’s-hub to the center of the journey axle’s hub.

It’s vital to keep in mind that wheelbase is just one of those trucking concerns that’s forever shrouded in controversy, confusion, and also misinformation. It’s plagued through a myriad of state and federal regulations that deserve to confuse even the many seasoned truckers.

So arrangement ahead if you will do it be operation in multiple states.


Weight Limits

The best gross load for tractor-trailers involved in interstate commerce in the United says is 80,000 pounds.

Trucks hauling oversized tons like mining equipment and also transformers are enabled much greater gross weights, yet they require special patent (and probably escorts) in each state v which they’ll travel.

For standard 5 axle semis, the best allowable axle weights are:

12,000 pounds ~ above the steer axle34,000 pounds ~ above the drive axles (on a tandem drive tractor)34,000 pounds ~ above the trailer axles

If you will do it be hauling freight into and out of Canada, you’ll have to familiarize yourself v their weight boundaries as well.

What are the Most well-known Trucks in America?

The sector for brand-new Class 8 trucks in the United states is conquered by the adhering to ‘Big 5’ manufacturers.


Freightliner’s sector share of new truck sales was standing at virtually 40%.

They’re well-built, reasonably priced, and have lower operating expenses than plenty of of your competitors, which makes them renowned with fleets and business savvy owner-operators.



Out top top the open up road, couple of truck brands command the respect the Peterbilt does.

They’re well-known for their lengthy hoods, smooth ride, and also high resale value, and also they’re perennial favorites with owner-operators trying to find all the bells and whistles.

Peterbilt van account for around 15% that annual new truck sales in the joined States.


Kenworths are known for their rugged durability, well-appointed interiors, and throughout the board styling that ranges from the classic W900 to the aerodynamic T680.

Kenworth and also Peterbilt space both own by Paccar, and also Kenworth’s market share is also about 15% of the brand-new truck market.

Navistar International

Though lock manufacture luxury trucks aimed in ~ owner operators as well, worldwide tractors space most renowned with huge fleets.

Compared with plenty of of their competitors, Internationals are fairly inexpensive, come in a selection of models ideal for different applications, and also have the reputation of standing up well in harsh working environments.

International’s market share is around 13%.


Known for your ergonomic driver amenities, plentiful engine options, and also all-around value, Volvo tractors are ending up being increasingly popular with fleets and cost-conscious owner operators.

They’re among the most aerodynamic and also fuel effective of every Class-8 trucks, and also they’re made as job cabs, heavy haulers, and also over-the-road tractors.

Volvo’s re-publishing of the new truck sector is about 9%.

Though castle account for more than 80% of brand-new sales every year, this manufacturers no the only options.


For an ext information on various other iconic American truck brands, click the links below:

Take a fast look at several of the most notable truck models native the past and also present:

Buying a large Rig

Though lock sure room nice to look at, shiny brand-new trucks through chrome stacks, aluminum wheels, and also posh sleepers might not be wise options for first-time drivers.

The trucking sector is fraught with difficult to know regulations, unanticipated pitfalls, and also economic components that have the right to vary greatly from one month to the next.

Many brand-new drivers invest a year or 2 driving agency trucks prior to making the leap come owning their own rig.

If purchase is best for you, you’ll want to think about the following questions:

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Should ns buy a new or supplied truck?

In most cases new trucks watch better, drive better, and smell far better than their used cousins. They also come v warranties—and price tags that regularly top $130,000.

Sometimes those warranties don’t offer the defense that buyers think lock do, and these days plenty of used van come through warranties of their own.

In many instances, well-maintained, low-mileage tractors are good alternatives to new ones.

Related > Tips for Buying a Used big Rig

Where deserve to I purchase a big rig?

If you buying brand-new you’ll be taking care of an main manufacturer’s dealership, but if you go the provided route you’ll have the option of purchase from used truck lots and private sellers.

Many brand-new truck dealerships also offer gently-used and also factory reconditioned trucks, and also for those searching for peace of mind, they’re usually safer bets 보다 the other two options.

That being said, few of the ideal used truck deals you’ll ever discover will come native owner operator who have actually meticulously kept their rides over the years.

In this case, castle should have actually the receipts come prove it.

How will certainly I finance my truck?

If you will do it be operating under your very own authority, you’ll have to pay for your truck v cash or finance it v a bank.

If jae won is the only option, you will do it be required to carry out documentation prefer a freight contract, or proof the you’ve successfully completed a van lease or purchase in the past.

Large carriers through owner operator departments may likewise have financing options available.

Find more specific truck financing information here.

Can i lease a truck from a trucking company?

Yes girlfriend can, however that doesn’t average you should.

Lease operator programs have the right to seem favor an attractive alternative for those do the change from firm driver to owner operator.

But in countless instances carrier leases room little much more than a scheme trucking carriers use to food on unwitting chauffeurs by saddling them through the hazard of owning a truck, without actually passing on any type of of the rewards.

Though there might be decent options out there, they’re certainly the exemption to the rule.

If you uncover an possibility to lease a van from a carrier you think is reputable, have an attorney evaluation their lease agreement prior to signing on the dotted line.

Related > i beg your pardon is Better? agency Driver or Owner Operator Career?

Other considerations…

Before do a huge decision prefer buying or leasing a truck, it’s constantly a great idea to talk through those who’ve currently done it.

That method current and former drivers—especially those who’ve functioned with the firm you’re considering, or who have actually experience running under their own authority.

Hands down they’re walking to it is in your best resource, so look for them out and also pick their brains.

Insuring her Investment

Insurance. The really mention that it often tends to reason drivers undue confusion and irritation. It’s an expensive but necessary angry for those interested in buying and operating their own truck. Yet it’s not as facility as it’s made out to be.

First, identify what insurance you will do it need based on federal and also state regulations, the form of truck you’ll be buying, what you will do it haul, and also where you will do it haul it.

Find lots of beneficial information about insurance.


Learning to drive an 18 Wheeler

Operators of advertising vehicles choose tractor-trailers, intake trucks, and also cement mixers require CDLs.

CDLs come in three classes: A, B, and also C.

To journey tractor-trailers through gross weights up to eighty thousands pounds, you’ll need a class A license.

Commercial van driver cultivate is easily available. It’s readily available by big carriers through their very own driving academies, independent schools, and some community colleges.

Some large carriers subsidize the price of training for trucking institution graduates who commit to working for them as soon as they acquire their licenses.

They’ll generally reimburse college student a little percentage of the school’s cost over a number of months till they’ve met their employment obligation.

We have actually lots more information on paid CDL training.


Driver Pay and also Demographics

Truckers pay can run the gamut indigenous peanuts to large bucks, but most drivers’ pay falls somewhere in the middle.

Though they face the toughest driving conditions, long stretches far from their families, and excessive oversight and also regulation, over-the-road truckers regularly make less money than regional drivers.

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Detailed van driving work pay statistics.

Though males account for practically 90% of commercial drivers, women are entering the industry with enhancing frequency. That a trend that’s caught the eye of large fleets, that are significantly seeking out women as an alternative source of drivers.