As the weather work nasty , you may start to think more about your car ’s transmission — particularly , its ability to get you up and down turbid , snowy , or icy road . While you may have it off that two - wheel drive is n’t the best choice for drive inharsh weather , other terms are more confusing . Like , for instance , all - wheel ride versus four - rack drive . Do n’t all cars have four wheels ( at least when it come to sedans , S.U.V. , and other consumer vehicles ) ? AsJalopnikexplains , the remainder between all - cycle drive ( AWD ) and four - cycle effort ( 4WD ) is more than just semantics — and which type you need depend heavily on the form of driving you do on a regular basis .
When a railcar manufacturing business specifies something as two- , four- , or all - bike drive , the caller is referring to the tyre that receive power from the engine . With two - cycle parkway , the engine powers either the front axle or the back axle of the car , meaning that the engine is moving only the fronttiresor the back tires . The other axle is just rove along . When four - wheel cause ( sometimes referred to as 4x4 ) is engaged , meanwhile , the locomotive spread out all four wheels . This helps give the cable car extra adhesive friction on tricky surfaces like guts , ice , and gravel — so that even if one set of wheels ca n’t get traction on a slippery open , the other wheels might be able to .
The central word there is “ engaged . ” Traditionally , four - wheel drive means that your carcandrive with all four wheels , but you have to manually choose that choice . The relaxation of the clock time , you ’re in two - wheel crusade mode . As Ray Magliozzi of NPR ’s " Car Talk " onceexplainedto a auditor , four - bicycle drive is “ design to be engaged when you ’re already stuck , or in a specific post where you bonk you might get stuck — like in snow , sand , or mud . It ’s not designed for normal road use , and must be disengage before you push back on teetotal , paved roads . ”
In all - wheel effort , meanwhile , the gondola figures out what kind of traction you ask all on its own . It has sensing element that image out how much power should go to each wheel to give you the in force adhesive friction without any comment on your part . This is a useful feature for beat back in a variety ofdifferent condition , while a consecrate four - wheel drive mode might be better for seriousoff - roading .
Be warned : There are downsides to all that special traction . A railway car ’s engine has to bring harder to power all four wheel . Those engine are also heavier , which itself take more mogul to move . As a result , four - wheel or all - roulette wheel drive cars usually use significantlymore fuelthan your distinctive two - wheel drive model .
There are other caveat to this account : Full - clock time four - wheel cause elevator car do exist , but they disagree slimly from all - cycle drive vehicles because of how the two axle of the machine move in intercourse to each other . In four - wheel campaign , the front and rear rack are lock together so they whirl at the same rate ; in all - wheel drive , the wheel are n’t locked like this — different amounts of power go to the different wheel as want .
All this enounce , even if you live on somewhere with snowy winter , it does n’t needs mean you should spring for all - steering wheel drive . If you’redrivinga lot in inclement weather — say , if you hold up in South Dakota or Wyoming rather than cheery Southern California — wintertime tyre may actually be a lot more crucial than which wheels the locomotive is power . Need proof ? Watch the television comparisonhere .
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