What's the difference between All-Wheel-Drive and 4-Wheel-Drive? I know that some 4WD systems are only part time, but what about the permanent 4WD systems? Aren't they the exact same thing as AWD?
2007-01-31 10:03:31 · 5 answers · asked by trainkid22 2 in Cars & Transportation ➔ Other - Cars & Transportation
They are the same as long as they utilize the viscous coupler to differentiate the front to rear. 4wd usually has a way to lock the two together powerwise.
2007-01-31 10:12:27 · answer #1 · answered by done wrenching 7 · 0⤊ 0⤋
There are many types of 4WD and AWD systems available now. A typical part time 4WD system must be disengaged on dry pavement and usually has 2H 4H Neutral, and 4L options available. 2H being used on dry pavement. 4H being used on slick or unpaved roads, and 4L being used for severe offroad use, or when extra torque is needed such as recovering a stuck vehicle. Neutral is used for towing the vehicle.
All wheel drive is permanent 4WD allowing the computer in the vehicle control which wheels receive power. Some systems have a torque split at 50/50, others are 60/40 etc. However the system is setup, most all wheel drive systems do not offer low range gearing or neutral.
Permanent 4WD systems such as the Jeep's Quadra Trac 4WD is permanent 4WD which allows the Jeep to be driven in 4WD all time on all road conditions due to an open center differential that allows all wheels to turn at different speeds. This type of 4WD system transfers power to the axle with traction when a wheel slip is noticed. The driver doesn't have to make any adjustments the system automatically places the vehicle into 4WD. This system also has a 4wd Low range and a neutral position but does not have a 2WD option as the vehicle runs in a 4WD mode all the time. The Quadra Trac system is a 60/40 torque split, but power can be transfered 100% front or rear depending on traction needs.
I own a 96 Jeep Grand Cherokee with Permanent 4WD and the Quadra-Trac 4WD works great in the 4All Time position unless I'm doing extreme pulling or offroading then the 4WD Low Range gets used, but not very often maybe once a year.
Subaru has all wheel drive which is a 50/50 torque split all the time. Power is transfered to the front and rear axle equally no matter what the road conditions are, and low range gearing is not available.
2007-01-31 23:28:29 · answer #2 · answered by Bill S 6 · 0⤊ 0⤋
The difference is that AWD all 4 wheels are powered all the time. With 4 Wheel drive, you can select 2 or 4 wheels, 4 high gear and 4 low gear. It is a bad idea to have 4 wheels powered all the time, the transfer case will wear out faster that way.
2007-01-31 20:45:50 · answer #3 · answered by Anonymous · 0⤊ 0⤋
full time 4WD usually has a 4WD low setting.
2007-01-31 18:19:45 · answer #4 · answered by Anonymous · 0⤊ 0⤋
yes
2007-01-31 18:16:29 · answer #5 · answered by chardson90 1 · 0⤊ 0⤋