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parity
January 9th, 2007, 04:52 PM
Hi all car lovers :D
Plz tell me
-> Wats this 4 wheel drive in cars ??
-> Is it same as 4x4 written on some cars ?
-> Is this technology only for SUVs n Sedans or for any kind of car ?

I have lots of queries, as i am crazy for cars :cool: wud post all one by one :D

I know i can find all this on net but knowing from a Jat gives a better feeling :D

dahiyarules
January 9th, 2007, 05:19 PM
Most cars have 2-wheel drive. It means that the car's engine propels either the front pair or the rear pair of wheels.

If a car is a front-wheel drive (FWD), then the engine propels the front pair of wheels.

If a car is a rear-wheel drive (RWD), then the engine propels the read pair of wheels.

Some sports cars are RWDs because a higher horsepower is utilized more efficiently in pushing as opposed to pulling in the case of FWDs.

Most Sedan's are FWDs. FWD is a conventional concept.

Then comes the 4-wheel drive or all-wheel drive (AWD). Such a design is suited for vehicles with humongous engines because of the energy needed to propel 4-wheels compared to 2-wheels.

Most SUV's and pickup trucks come with 4-wheel (AWD) and 2-wheel drive variants. The AWD models cost more.

Such vehicles are good for bad terrain driving because each wheel needs more energy in such situations. AWD gives the driver a better grip over the terrain.

No, all cars that have AWD or 4-wheel drive written on them are'nt actually AWDs; especially in India where people put twin-cam-16 valve stickers on their single-cam- 4 cylinder maruti cars. You can put one such sticket on your moped. No one cares.

In the US, cars with 4-wheel drive or AWD stickrs on them are very probable to be 4-wheel drives or AWDs. Many people in the US are off-road enthusiasts. They have such vehicles for personal, or professional reasons, depending on where they live, work or have fun.

From my personal experience, AWDs are a lot of fun for off-road driving. They hardly make any difference while driving on paved roads. You wont even feel the 4-wheel drive when driving on an interstate.

In India, I think the only 4-wheel drive that I am aware of is the loyal Military Jonga. I dont know if Maruti Gypsy or some Mahindra and Tata vehicles are 4-wheel drive now. There were hardly any AWDs in INdia 6 years ago.

Ask any question you feel

sunitahooda
January 9th, 2007, 05:28 PM
4WD and AWD systems explained

A word of caution first. Manufacturers tend to hide the real nature of their 4WD systems behind phantasy names like "real time 4WD" etc. - others might call their system AWD when it is clearly not. Make sure you get what you really need.


4WD has been invented a very long time ago and various concepts have been tried. Here is a simplified synopsis of what is what. They are all 4WD, but have been given different names. Links within this page provide detailed insight.

Part time 4WD is a system that can only be used part of the time in four wheel drive.
This 4WD system was created to provide a vehicle with more traction to either carry higher loads and/or to travel in adverse terrain conditions. Clearly purpose built to do hard work. It can only be used for adverse terrain conditions - not for dry pavement.
Typical lever settings are 2WD, 4WD Hi, 4WD Lo.
Very good off-road. Most competent when combined with axle differential locks.
• 2WD setting must be used on dry pavement.
• If 4WD is selected, all 4 wheels are permanently powered.
Prominent examples: 1942 Willys, Jeep Wrangler.


Full time 4WD - also called permanent 4WD, can be used full time on all surfaces including pavement.
Full time 4WD was created to provide a vehicle with more traction and to make 4WD more useful for everyday life. The additional feature of a differential incorporated into the transfer case makes it possible to use 4WD all the time.
2WD is no longer available. Can still be a strong workhorse. Some rough terrain competence is retained - the priority is added stability as a safety gain for everyday driving.
Typical lever or switch settings are 4WD Hi, 4WD Lo. Very good off-road when center diff is lockable. Even better when combined with axle differential locks.
• All 4 wheels are permanently powered.
Prominent examples: pre 2006 Mercedes M-Class, Mercedes G500, LandRover, RangeRover.


Full time symmetric AWD is similar to full time 4WD - only it lacks the slow speed torque enhancing low range feature. Can be used full time on all surfaces including pavement.
Symmetric AWD was created as a safety feature for modern day vehicles. Not designed for hard work. Clearly a safer, more comfortable vehicle. Rough terrain competence has almost vanished - focus is on added stability and performance.
Limited use for off-road.
• All 4 wheels are permanently powered.
Prominent examples: 2006 Mercedes M-Class, Audi Quattro, most Subaru, pre 2006 RAV4


Automatic asymmetric AWD was created solely as a stability enhancing system. Auto AWD can be used full time on all surfaces including pavement. AWD only briefly activates automatically when stability threatening conditions arise. Essentially a 2WD car with 2WD handling characteristics. Absolutely no adverse terrain capabilities. Clearly built for added road stability and safety.
Not recommended for off-road beyond graded dirt roads.
• 2 wheels are powered most of the time
• 4 wheels are only temporarily powered.
Prominent examples: Volvo AWD, 2006 RAV4, Honda CRV.

A more detailed explanation of the differences between 4WD and AWD.

So, is "real time 4WD" really 4WD? No, it is a sophisticated 2WD car with automatic asymmetric AWD. There is no commonly accepted standard - companies and especially their PR departments use terms for 4WD systems very loosely - transparent consumer information is not their priority.

Many vehicles are offered with a combination of the systems outlined above.

sunitahooda
January 9th, 2007, 05:30 PM
Samta for more info log on to 4x4abc.com i hope this pacifies your query:)

parity
January 11th, 2007, 08:52 AM
Thank u Sumit n Sunita for explaining so beutifully :)

Any relation between 4 wheel drive or AWD & mileage of the vehicle ?
I guess not :D but plz tell.
Is this mean that it can be used only in powerful vehicles ?

dahiyarules
January 11th, 2007, 02:21 PM
Thank u Sumit n Sunita for explaining so beutifully :)

Any relation between 4 wheel drive or AWD & mileage of the vehicle ?
I guess not :D but plz tell.
Is this mean that it can be used only in powerful vehicles ?
er

Ofcourse AWDs gulp more petrol compared to non-AWDs. Such cars have bigger engines that produce higher torque, which needs more petrol.

Engines have to be a certain specification to handle AWD capabilities of a car. You cannot have a meaningful AWD in a Maruti Car with a 800 cc engine.

But, dont miss the point. The main reason people buy AWDs is because they need more power in their wheels.

chhillar
January 12th, 2007, 02:44 AM
Sumit bhai AWD ka to karda parcha chhaap diya dyaki...ye saari florida ki AWD te taane dekhte he daank maarengi beri

dahiyarules
January 12th, 2007, 12:30 PM
Sumit bhai AWD ka to karda parcha chhaap diya dyaki...ye saari florida ki AWD te taane dekhte he daank maarengi beri

Chillar Saab! I love machines. :)

downtoearth
January 12th, 2007, 10:33 PM
In old mahindra and gypsy, one had to adjust the hubs manually for 4*4 operation....there is an option in 4wd i.e 4 low and 4 high

4 low...>>> engine can give u instant pick p but cant touch the top end...like ,, machine touches 100 kmph in second gear,,but after applying 4 low speed`ll decrease to 60kmph .....u can use 4 low in sand dunes ....;)

4high ..>>>engine cant give u instant pikp but can touch the top end..now engine`ll cut out at 130 in second gear....after touching the top end engine starts giving sound like PPPPPPPPPP....:)

u can shift the lever 4low to 4 high any time but u cant shift it back to 4low..for that u have to stop the car.....

i lv suvs for their off-road style...

my fav off-roaders >>>> gypsy and mitsubishi strada {in the pic}

cooljat
January 12th, 2007, 10:40 PM
Indeed gud informative inputs from Sumit, Rupi & last but not the least Hoods Bolero aali :rolleyes: ;)

Rock on
Jit

parity
January 13th, 2007, 06:42 PM
In old mahindra and gypsy, one had to adjust the hubs manually for 4*4 operation....there is an option in 4wd i.e 4 low and 4 high

4 low...>>> engine can give u instant pick p but cant touch the top end...like ,, machine touches 100 kmph in second gear,,but after applying 4 low speed`ll decrease to 60kmph .....u can use 4 low in sand dunes ....;)

4high ..>>>engine cant give u instant pikp but can touch the top end..now engine`ll cut out at 130 in second gear....after touching the top end engine starts giving sound like PPPPPPPPPP....:)

u can shift the lever 4low to 4 high any time but u cant shift it back to 4low..for that u have to stop the car.....

i lv suvs for their off-road style...

my fav off-roaders >>>> gypsy and mitsubishi strada {in the pic}

Thanx :) But Sir Ji ye "4 low & 4 high" kya hai ?

vijay
January 14th, 2007, 06:44 PM
In old mahindra and gypsy, one had to adjust the hubs manually for 4*4 operation....there is an option in 4wd i.e 4 low and 4 high



I had Gypsy and it was fun to explore deserts of Rajasthan. :)

downtoearth
January 14th, 2007, 08:30 PM
I had Gypsy and it was fun to explore deserts of Rajasthan. :) gypsyyyyyy,,,,,,man im hardcore fan of maruti gypsy.....:):):)............let me share sm pics of last desert rally....... enjoy...

downtoearth
January 14th, 2007, 08:40 PM
I had Gypsy and it was fun to explore deserts of Rajasthan. :) .............

vijay
January 14th, 2007, 08:40 PM
gypsyyyyyy,,,,,,man im hardcore fan of maruti gypsy.....:):):)............let me share sm pics of last desert rally....... enjoy...


Gr8 pics Rupi..... really movvvvingggggggg :)

trueblueindian
January 14th, 2007, 08:54 PM
Hi all car lovers :D
Plz tell me
-> Wats this 4 wheel drive in cars ??
-> Is it same as 4x4 written on some cars ?
-> Is this technology only for SUVs n Sedans or for any kind of car ?

I have lots of queries, as i am crazy for cars :cool: wud post all one by one :D

I know i can find all this on net but knowing from a Jat gives a better feeling :D



well so far so gud really nicely explained by members...

further sukarma few basic things to keep in mind.....

1. 4 wheels consume fuel like anyting... and more so the speed and initial acceleration is also hampered to a great extent so permanent 4WD is useless and i guess isnt also available in india......

2. in india there r many varients ... age old Gypsy (i luv this machine), TATA safari, scorpio, Ford endauver, nissan X - trail, pajero, parado, audi n many more (sumit many models were very much here even 6.....(10) years back)

3. in applied senses and for all practical purposes 4WD is used once in a blue moon here....

4. they r expensive then normal ones so buy if u reallly need to travel through rough patches and are an adventurer.

5. i wonder if any sedan has a 4WD

6. u said urself.... in india 4X4 written on it means nothing except the guy driving it is a freak...... like in many cases u would find TWIN CAM 16 VAULVE written on a maruti - 800..... hahhahahahhahaa.... even u would find it on safari's and scorpios written falsely... i juss donnno why ppl do such things.... may be inferiority complex......hahhahahahhahahaa