Is there a difference between AWD and 4WD?

Question

If so, what?!

Answer 1

4WD is usually a rear drive truck or SUV with the capability of 4 wheel power. The suspension and steering are engineered for full-time rear drive, and 4 wheel is used in snow or mud. It has to be switched to 4wd by the driver. AWD has power available to all wheels all the time, usually computer controlled as to which wheels need the power. It will drive in 2wd mode when the computer senses stable conditions, and transfer power automatically if more traction is needed front, back, or either side.

Answer 2

Full time 4WD, also called permanent 4WD, (not to be confused with: part time 4WD ) is a system that powers all four wheels at all times and can be used full time on all surfaces including pavement. 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. Each tire creates about 25% of the available torque when the ground is level with a consistant surface. Driver has a choice of a "4-high" (that's your every day setting) and "4-low".
Full time 4WD vehicles work very well on-road and are very capable off-road.

All wheel drive (AWD) is almost the same thing as full time 4WD - it is a system that powers all four wheels of a vehicle at all times as well. Full time symmetric AWD would be the best term to be used. Difference to full time 4WD is that a "4-low" setting is not available in AWD cars. Due to the lack of "low range" AWD vehicles are much less capable in off-road settings than full time 4WD vehicles, but work perfectly well on-road.

Automatic AWD system is the newest kid on the block. PR agnecy generated names like "Real Time 4WD", "intelligent AWD" or "active AWD" are hiding the fact that automatic AWD is essentially a sophisticated 2WD system. Automatic asymmetric AWD would be the best term for them.

Here is how they work: Under normal conditions one axle gets 100% of the torque - meaning you are driving in 2WD. During traction loss at the driven axle (could be front or rear) a fully automatic system (hydraulic, mechanical or electronic) makes up to 50% of the torque to the axle with traction available. This means you have to lose traction in 2WD on your driven axle first and then the other axle will be added and try to keep the car moving and stable. Once the primary driven axle regains traction and both axles rotate at the same speed again, the system reverts back to 2WD. So, for a moment you had AWD.

Automatic asymmetric AWD is much less capable in off-road settings than full time AWD systems and inferior to full time 4WD. However, automatic asymmetrical AWD is becoming more and more sophisticated and offers pretty much everything consumers expect for everyday (pavement) driving.

Answer 3

Yes.

4WD is not meant to drive on pavement as the transfer case has a direct drive to all four of the wheels. The differences in speed of the tires in turns and other maneuvers cause undo stress on the drive-train and also wears out the tires prematurely.

AWD has a fluid coupling in the transfer case. It was invented decades ago by a man called Ferguson and it uses silicone instead of gears to transfer the torque to the wheels that need the power while allowing a bit of slippage to ease the stress on the rest of the drive-train.

Answer 4

Yes there is, the AWD has the gears engaged at all times, creating better traction, and turning ease is improved. 4WD, is used when you would be off road, on muddy,rugged terrain, or sandy beaches. Subaru vehicles are all made AWD, they off road well, but may lack clearance needs.

Answer 5

wow, a few exciting solutions, a few right a few improper. Here is the inside track: A 4 wheel drive procedure is frequently refers to a auto which has a middle locking differential, which lock the entrance and rear axles in combination, so they are going to each flip on the identical pace. But the style of axle additionally makes a enormous change, a few are open, and a few are constrained slip, posi, antispin and so on. AWD frequently refers to a procedure which doesn't have a middle differential. Many automobiles at present use a viscous style coupling to switch vigor among axles headquartered on slipage.

Answer 6

4wd must be shifted into 4 wheel either manually or electrically.

AWD will always have the 4 wheels engaged. Fords 500 will apply power to the front wheels and if they spin it will divert power to the rear wheels without any driver input. It's all automatic.

Answer 7

yes. 4wd has an engagable transfer case while AWD is full time.

Answer 8

yes awd is all the time 4wd, you can not turn it off

Answer 9

AWD: fulltime
4WD-able to be turned on and off

Answer 10

Yes,If you have a All wheel drive vehicle all four wheels have power to them,If you have four wheel drive you can choose if you want it in two wheel drive or four wheel drive.All wheel drive can be used on dry roads,four wheel can not