AWD, 4WD or 4x4


#1

what is the difference with AWD, 4WD and 4x4?



is one better than the other?


#2

These get used in very confusing ways by the car makers. Honda calls their system 4WD I think, while others would call the exact same system AWD. The definitions I’m used to would be
4WD - where you can flip a switch/pull a lever/push a button and all 4 wheels are driven, typically without a center differential (old style SUVs and pickups)
AWD - typically no action is needed, the system is ‘on’ all the time, there’s a center diff to allow use on dry pavement. These can have a button that locks the center diff in slippery conditions, changing it to a 4WD system.
4x4 - more associated with 4WD

That said, all these terms have become pretty much interchangeable, you need to check out the system you’re dealing with.


#3

AWD is full time, there is no switch for the driver to fiddle with to turn AWD on or off.

4WD and 4X4 are the same animal. They operate in 2WD (usually the rear wheels) until the driver engages the 4WD either with an on/off switch or a lever and some vehicles have both. Most truck and SUV’s have 4WD L, or low, which is a very low gear ratio useful for off-road use.

There are unique features some manufacturers use in their vehicles so the systems are similar in operation but can be very different in technical, design, and mechanical aspects.


#4

Is one better than the other ?

This is relative to YOU and your diving style, only YOU can decide.

My example is this ;
My wife and I need both systems. AWD for her ( 06 Escape hybrid ) and 4x4 for me ( 08 Expedition & previously 92 Explorer ).

She is never sure when to use , or NOT use the 4x4. She’s tone deaf and can’t hear the engine race when the tires spin. She just can’t get the feel of the vehicle in her big toe so as to feel tire slip or slide.
For her AWD is the answer with no thinking needed, just the cautionary driving associated with the bad weather.

I want to switch it when I need it. People call me for help and I’ve needed low range for several pull outs. If there’s any off-roading or super bad weather it’s me who drives.


#5

Good explanations. Generally, they are all “good” systems as long as you use them as each was intended by following the owner’s manual.

There are SUVs/trucks and cars that offer both AWD and 4wd functions to some extent. I would disregard the 4 by 4 label as it’s a very vague reference to 4 wheels that can be powered at some time or another.

What also gets a little confusing is that traction control, limited slip differentials and all that other stuff when thrown into the mix, enhance the performance of both systems.

I agree that instead of labels, you look at the intended use capabilities of each vehicle as described by it’s manufacturer and match it up to what you want the vehicle to do. You’ll go crazy trying to label these systems unless both you and the person you are talking with can agree on your terms.


#6

The Honda thing gets really confusing unless you agree that a 4wd does not have a center differential and just a transfer case. Then CRVs are 4wd with an active clutch set up in the rear diff that makes it perform like other awd cars with center differentials.
Then technically they (Honda) are correct. That’s why I agree with you that it’s really a function and not a mechanical set up question for most of us.
And generally it’s 4wd if the front and rear are locked in at 50/50 torque distribution and awd if it can vary on it’s own w/o addition input from the driver.


#7

AWD is a marvelous system by which car manufacturers can extract an extra $3000 out of you so, 98% of the time, when you are driving around on dry, clear roads, you have all 4 wheels powering the car…The system demands you always must purchase 4 new tires whether you need 4 new ones or not, it has two more drive-shafts to worry about including 4 more CV joints for a total of 8…The power-splitting transfer case, should it fail, brings tears to the eyes of thousands of AWD owners every year and keeps hundreds of repair shops busy…But the 2% of the time when he streets are snow-packed and icy, NOW you are in business!


#8

Well spoken by a warm weather flatlander. :=) I agree that half the people out there only buy them out of unfounded fear, perhaps. But with all due respect there is a legitimate group out there who really want to travel more safety with them in both slippery and dry conditions. The rest of the fear, the expense of tires and maintenance is just that…fear unfounded in reality. FWD cars eat up tires at a much higher rate. If the number of increased parts meant less reliability, today’s cars wouldn’t be more reliable, and they are, than yesterday’s.

If you buy unreliable 2wd cars, the awd cars from the same car company will be just as unreliable. If that’s your experience in the cars you buy, I then agree with you.


#9

FWD eat up tires at a higher rate than AWD? Why? AWD still has driven front wheels under the engine. The difference is that if my front tires on my FWD are bad, I can replace them and leave the rears alone. That would tear up my AWD system if I tried that.

As for the flatlander comment, I’ll remind you that people used to (and still do) drive RWD pickup trucks and vans in the Rocky mountains. The idea that we need AWD or the mountain will kill us is silly fearmongering. In all the years I lived in the Rockies, I never managed to drive off a cliff despite the lack of AWD or even 4x4.


#10

First, I am a HUGE fan of rwd cars and trucks and find awd for most a response to fwd problems in cars, especially on hills. RWD to me is the ultimate expression of overall vehicle utility except for off road use. I have never mentioned the comparison to rwd cars and trucks. Where did you get that and the fear mongering bit ?

As far as FWD cars eating up tires, it’s an obvious fact that tires on wheels used both for turning and acceleration, undergo much more stress and wear. So much so, even frequent rotations can’t compensate for the difference. FWD car tires are therefore much more susceptible abnormal wear patterns which make tire rotations problematic. If all you’re doing is replacing your front tires, it’s an unsafe practice and unnecessary in rotated awd and rwd cars.

AWD cars, {and can I assume you have owned one} manage torque during acceleration so for many cars, as much as 90% is shifted to the rear making it practically a rwd car. The cv joints likewise experience reduced stress because of this as the torque is again transferred away during turning to a non turning rear wheel.

FWD in police work in our state, where problems with stress are amplified over a shorter period is restricted to detective work. Feeble attempts at using fwd cars for regular duty in our state has been disaster. Inner city, perhaps, but according to the members of departments I’ve talked to, they ate up tires like you wouldn’t believe. We always had rwd crusiers and lobbied our town against such experiments.

If you have awd and rotate tires according to specs, your tire wear is dramatically better than fwd cars. In 40 years of driving, comparing the many of my fwd cars, like Hondas and Toyotas and awd cars like my Subarus and RAVs tire wear has been every bit as good as my Ford and Chevy rwd cars and trucks. They were all treated the same. Take care of a tire the way it’s recommended for any car, and you will have NO related problems with AWD system what so ever.
AWD for police work is touted as a safety factor for handling, even above the rwd crown Vics. Maybe, but it’s in only a response to going to the fwd chassis in the Taurus that that need is even there. RWD is the best for most needs, awd/4wd is better in some high traction needs, fwd stinks for all but economy of manufacturing and space utilization which relates to fuel economy indirectly.

Just for the record, the life span of tires on ALL my awd cars have far exceeded their warranty miles. Not even close in comparison to my fwd cars.


#11

I have never mentioned the comparison to rwd cars and trucks. Where did you get that and the fear mongering bit ?

Because a RWD pickup trying to go up a slippery hill is just about the worst vehicle to use, since there’s almost no weight over the drive wheels. The fearmongering bit comes from the fairly common attitude around here that people who say AWD is unnecessary are flatlanders who don’t have to deal with the perils of mountain driving. Well, I did, had no AWD, and survived just fine.

I agree with you regarding FWD cars and police work - though I approach it less from a maintenance standpoint and more from a “it’s easier to catch the speeding bad guy if you can floor it without wheel hop” point of view - but I’ll point out that there are few if any people on here asking for advice on what cop car they should buy for patrol. We’re talking normal people using cars normally - and on that note you have to keep in mind that most people don’t bother to learn proper throttle control, which means that the greater handling potential of RWD becomes a liability because they don’t have the practice or ability to properly control that throttle, which means that they tend to fishtail when they try.

For the record, I think AWD is just fine, and a definite enhancement in certain applications. But saying that anyone who says AWD is not a necessity must by definition be a flatlander who only drives in warm weather is stretching it by a pretty hefty margin. AWD is really nice when driving on a snowy mountain road, but it’s not necessary - and if conditions are so bad that it becomes necessary, they probably exceed the driving ability of most of the people who might stay home if they didn’t have the perceived safety margin of AWD.

For the record, while I have driving 4wd and AWD vehicles for work, I own two FWD’s and one mid-engined RWD. Of the three, the mid-engine one eats tires by far the fastest. I got 52k out of the factory tires on my TL, and get around 30k on the tires on my CRX, which gets summer performance tires that see autocross duty, so tire wear really isn’t such a big factor.


#12

"For the record, I think AWD is just fine, and a definite enhancement in certain applications. But saying that anyone who says AWD is not a necessity must by definition be a flatlander who only drives in warm weather is stretching it by a pretty hefty margin. "

I hope you saw the :=)…it was in jest as for the most part fwd shows it’s true weaknesses on hills and in slippery conditions. Again, awd is IMO a response to fwd. RWD unweighted trucks are a disaster only if you don’t realize that trucks are MEANT to be weighted. They are engineered to accommodate weight and any attempt to add weight (up to a point) only makes for better traction and handling. The exact opposite is true with fwd. AWD accommodates a much wide load carrying range than either drive system. I have ice racing experience which reveals handling deficiencies of all drive trains in emergency maneuvers. FWD is really poor.

Last comment about probably should stay home if you need AWD is an unfair assumption as I LIVE on a snow covered mountain road for 15 years, that CANNOT be traveled safely with fwd in the winter.
This is it…please excuse the cheap camera work. http://www.youtube.com/watch?v=ZF0TmDm985I


#13

I can compare 2 cars, a jeep something or other with awd all the time that is lucky to get 12 mpg. My blazer with 2wd, auto, 4hi and 4 lo has a bigger engine and is 16 mpg city and 22 mpg highway. The auto engages the front axle, but only kicks in four wheel drive as needed. I love it! How often do I use auto, at most 5 or 6 times per year due to snow and ice etc. I grew up on 2wd from the rear and love the extra gas mileage. My 2 cents. I need the vehicle for boat towing and 4wd lo for pulling the boat out of launches I use.


#14

I don’t KNOW ANY AWD system that’s as unreliable as Caddyman makes them out to be. Maybe he should stop driving Caddies if they’re that unreliable.

AWD system’s are fine for driving around in snow as long as it’s not too deep.

4wd is better for deeper snow and off-road. I also like 4wd on dirt roads or mud roads…especially when towing my camper.


#15

Some of us have trouble free systems that allow you to experience 2wd, awd and 4wd with low range all with the same vehicle. Neighbor has close to 300k miles on her suv with no drive train problems what so ever. Of course, we are alL driving the same make, and it’s not a GM product I’m sorry to say.


#16

your road looks very similar to the one I lived on actually, except for the lack of switchbacks and occasional 500-1000 foot dropoffs. I did just fine in a little FWD hatch back. Never had to walk up the mountain to get home. I think you’d do just as well in the conditions you showed with any drive train configuration except rear/mid-engine. You’d have to slow down some (but then as one of your commenters noted you should probably do that anyway).


#17

The poor quality does not give you a feel for the steepness. Also, the narrow passage means someone has to back down or start up on the hills on occasion. NONE of the fwd cars in the area, even with the adored studded snow tires function reliably in the winter here.

I guess you’ll have to trust my opinion on “been there and tried with fwd” after 15 years. The only vehicles in 2wd that have a chance are rwd trucks with good tires and lots of weight in the back. Contractors with limited slips work well…until they land in the 4 foot ditches. Then my tractor gets a work out. Conditions here, finish with rain on frequent storms and ice over.

We don’t walk w/o studded shoes either. With 20 houses on the road, NO ONE depends upon fwd in the winter past the first third. EVERYONE past the first hill coming in the 1.5 mile private road has at least one 4wd/awd. Many rural areas in my state are similar. BTW, it’s the cheap camera that appears to show excessive speed:it’s a 15mph trip.