Influencer III
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Is 4x4 better than 4x2?
- Thread starter Overland Commander
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- 4x4 overland driving safety
Member III
Watching the skid pad video a few times, it appears he was having to counter understeer through overly-aggressive steering angles. Then, when the front wheels caught (i.e. potentially when slightly reducing throttle), it caused an oversteering tendency, which was difficult to counter because the rear end was already coming around before he could get the steering wheel cranked back the other direction. Science checks!
That said, I have been doing motorsports for a couple decades now, and I know what it looks like when somebody is maybe not doing everything they can to not get sideways. And, to be honest, watching the front wheels and his steering inputs inspired some noslalgia in that regard ;) .
That said, I have been doing motorsports for a couple decades now, and I know what it looks like when somebody is maybe not doing everything they can to not get sideways. And, to be honest, watching the front wheels and his steering inputs inspired some noslalgia in that regard ;) .
Influencer III
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Expedition Master III
When i was just a lad, my father bought a brand new 1967 Dodge(D200/3/4 ton) 2 wheel drive pickup. We went everywhere in that truck. He purchased the 4x2 wheel vs the 4x4, because people told him the 4x system would lock up if not used enough. Being his first truck ever, he listened to that advise, and regretted not getting the 'Power Wagon' instead. I remember many times digging trenches and throwing rocks under the rear wheels to get unstuck.
My first pickup was a 4x4, as were my subsequent ones. The adage better to have and not need than not have and need always stuck with me. It has been true a few times.
My first pickup was a 4x4, as were my subsequent ones. The adage better to have and not need than not have and need always stuck with me. It has been true a few times.
Influencer I
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There is merit to what is said there but as noted above in 4wheel there was horrendous under steer which can cause just as many issues as over steer. The key really is knowing how your rig reacts in an extreme situation, and how you personally will react in that same extreme situation.
For me even in terrible ice and snow on road, in rigs with selectable 4x4 I will leave them in 2 until I literally will not move. Then as soon as I am rolling I will kick it out of 4. My thinking is if its so slick that I am having a hard time getting moving, it will be ten times worse stopping. Also if you drive attentively there is TONS of feed back from the rig about traction that can be lost in 4. I will even apply this same train of thought, though to a lesser degree off road.
Now I own 2 computer controlled AWD rigs, so when its slick I just mash the throttle and make that traction control system earn its keep, LOL!
For me even in terrible ice and snow on road, in rigs with selectable 4x4 I will leave them in 2 until I literally will not move. Then as soon as I am rolling I will kick it out of 4. My thinking is if its so slick that I am having a hard time getting moving, it will be ten times worse stopping. Also if you drive attentively there is TONS of feed back from the rig about traction that can be lost in 4. I will even apply this same train of thought, though to a lesser degree off road.
Now I own 2 computer controlled AWD rigs, so when its slick I just mash the throttle and make that traction control system earn its keep, LOL!
Member III
Of note, it has been proven over and over that 4WD does not necessarily help you turn better except on extremely lose or slick surfaces. Though, like mentioned above, on those surfaces you are probably also going slow enough that the difference is still neglegable.
http://fastestlaps.com/lists/top-grip-kings
Note it wasn't until #28 of 100 that we even see the first 4wd model :) .
http://fastestlaps.com/lists/top-grip-kings
Note it wasn't until #28 of 100 that we even see the first 4wd model :) .
Not really sure what they were trying to get across there but I'll give it a shot.
These videos don't really explain of much of why things happen but they do demonstrate a little that is helpful. First, people complain about understeer but it is is designed into vehicles because the majority of people can't handle oversteer. When the tail kicks out, they freak out, grab a hand full of steering and jam on the brakes as hard as they can. Bam, instant loss of control. 4wd can help overcome that on loose or slick surfaces.
You can argue that you don't need it 4wd while driving faster than you should on loose surfaces but that will only go so far. If you are driving too fast in dry dirt, yes, you can recover and be fine. In snow, ice and slick mud, the extra control 4wd offers can keep you from crashing by allowing all the tires to have some input on speed and vehicle control. 4wd won't stop you any faster but it will help directional control immensely in those situations where no matter how slow you go, there isn't enough traction to allow you to follow the road or to avoid obstacles.
That is where adding power and steering where you want to go comes in. You are no longer along for the ride at that point, you are doing something about it. The old adage of leaving it in 2wd until you can't go further or absolutely need it is false economy and can really hang you out to dry unnecessarily. I've driven a lot in loose and/or slick conditions and used to believe in the 2wd theory until I began driving fast for a living in poor conditions. Having the ability to steer where you want to go and accelerate sure beats letting off, counter-steering and hoping the tail doesn't pass you due to inertia overcoming traction. AWD won't help you much here without traction control because it will transfer all the power to the tires with the least amount of traction. That is usually the tires that are sliding sideways and that weight transfer has lifted from the ground or unloaded severely.
On the subject of AWD vs. 4wd they both have their places but in an AWD vehicle, you can have all kinds of issues if you are not used to driving a car that will transfer all the power to the wheel with the least amount of traction. If you turn a car sideways, that will be the tire that is trailing and has the least amount of weight on it. Unfortunately, it will do you almost no good to add power to that tire since it won't have enough traction to do much more than emit smoke or sling loose surface material around unless you have some sort of electronic traction control.
Driving habits are also part of the equation. If you are used to a front wheel drive car, it will almost always understeer or "Plow" until enough friction builds heat into the contact patch or in dirt, until the speed drops enough to allow the available traction to overcome the vehicle's desire to go straight. This is due to the design and the weight bias. A rear wheel drive car can induce over-steer by throttle on or throttle off. AWD vehicles can have the worst of both worlds built in and a 4wd vehicle can have the best of both worlds, or the worst, depending on the surface and driver inputs.
As for the trailer show. Pulling a trailer increases over-steer because the trailer is pushing the tongue in a straight line. The truck is trying to turn, the trailer wants to go straight. Being in 4wd allows the driver to accelerate the truck and pull it back straight. If you've never lost it in a corner with a trailer, you won't fully grasp the importance of having a manual way to activate trailer brakes ready at your fingertips or the control that 4wd will bring to that situation. 4wd also forces the front tires to keep up with the rears and vice-versa. Letting off the throttle can cause the rear tires to stop rolling and start sliding sideways and as this happens, the front inside tire can stop rolling as well; causing big problems that cannot be overcome with talent. 4wd causes all the tires to at least want to keep moving, absent differential action.
On the subject of recovering from a slide, although I'm not a huge fan of auto transmissions; there is merit in being able to grab the trailer brakes and stab the throttle without having to gear down to get enough power to do the job.
These videos don't really explain of much of why things happen but they do demonstrate a little that is helpful. First, people complain about understeer but it is is designed into vehicles because the majority of people can't handle oversteer. When the tail kicks out, they freak out, grab a hand full of steering and jam on the brakes as hard as they can. Bam, instant loss of control. 4wd can help overcome that on loose or slick surfaces.
You can argue that you don't need it 4wd while driving faster than you should on loose surfaces but that will only go so far. If you are driving too fast in dry dirt, yes, you can recover and be fine. In snow, ice and slick mud, the extra control 4wd offers can keep you from crashing by allowing all the tires to have some input on speed and vehicle control. 4wd won't stop you any faster but it will help directional control immensely in those situations where no matter how slow you go, there isn't enough traction to allow you to follow the road or to avoid obstacles.
That is where adding power and steering where you want to go comes in. You are no longer along for the ride at that point, you are doing something about it. The old adage of leaving it in 2wd until you can't go further or absolutely need it is false economy and can really hang you out to dry unnecessarily. I've driven a lot in loose and/or slick conditions and used to believe in the 2wd theory until I began driving fast for a living in poor conditions. Having the ability to steer where you want to go and accelerate sure beats letting off, counter-steering and hoping the tail doesn't pass you due to inertia overcoming traction. AWD won't help you much here without traction control because it will transfer all the power to the tires with the least amount of traction. That is usually the tires that are sliding sideways and that weight transfer has lifted from the ground or unloaded severely.
On the subject of AWD vs. 4wd they both have their places but in an AWD vehicle, you can have all kinds of issues if you are not used to driving a car that will transfer all the power to the wheel with the least amount of traction. If you turn a car sideways, that will be the tire that is trailing and has the least amount of weight on it. Unfortunately, it will do you almost no good to add power to that tire since it won't have enough traction to do much more than emit smoke or sling loose surface material around unless you have some sort of electronic traction control.
Driving habits are also part of the equation. If you are used to a front wheel drive car, it will almost always understeer or "Plow" until enough friction builds heat into the contact patch or in dirt, until the speed drops enough to allow the available traction to overcome the vehicle's desire to go straight. This is due to the design and the weight bias. A rear wheel drive car can induce over-steer by throttle on or throttle off. AWD vehicles can have the worst of both worlds built in and a 4wd vehicle can have the best of both worlds, or the worst, depending on the surface and driver inputs.
As for the trailer show. Pulling a trailer increases over-steer because the trailer is pushing the tongue in a straight line. The truck is trying to turn, the trailer wants to go straight. Being in 4wd allows the driver to accelerate the truck and pull it back straight. If you've never lost it in a corner with a trailer, you won't fully grasp the importance of having a manual way to activate trailer brakes ready at your fingertips or the control that 4wd will bring to that situation. 4wd also forces the front tires to keep up with the rears and vice-versa. Letting off the throttle can cause the rear tires to stop rolling and start sliding sideways and as this happens, the front inside tire can stop rolling as well; causing big problems that cannot be overcome with talent. 4wd causes all the tires to at least want to keep moving, absent differential action.
On the subject of recovering from a slide, although I'm not a huge fan of auto transmissions; there is merit in being able to grab the trailer brakes and stab the throttle without having to gear down to get enough power to do the job.
Traveler III
@wlld420 Good points. I also find your comment on weight distribution bias very interesting. It's a factor that I think is often overlooked, and perhaps underappreciated. Having a vehicle with nearly exact 50/50 weight distribution is probably an advantage that few take into account.
Influencer III
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The front powered wheels are sort of the old thing about "is it easier to push a steered cart od pull it" that we have all experienced at Home Depot. Pulling has something to do with it, for sure.
I go into 4WD any time the surface is wet or slippery. The safety margin is noticeable in the feel and handling of the truck, and it keeps my 4WD driving skills sharp. Its there. Use it!
Hes right about not waiting until 2WD runs out before engaging all 4. I think of 4WD as a preventive. And because I practice, well....
Last weekend at a field trial I was running another Gunner to his post over deep rutted tracks. He commented on how the Sequoias handled the ruts so smoothly and how other trucks would bounce people around. I told him "I appreciate that, and its a fine truck, but off-road its all about the line you pick". 2WD or 4WD, practice and be smooth. Use the 4WD as the protective factor, thats my motto.
I go into 4WD any time the surface is wet or slippery. The safety margin is noticeable in the feel and handling of the truck, and it keeps my 4WD driving skills sharp. Its there. Use it!
Hes right about not waiting until 2WD runs out before engaging all 4. I think of 4WD as a preventive. And because I practice, well....
Last weekend at a field trial I was running another Gunner to his post over deep rutted tracks. He commented on how the Sequoias handled the ruts so smoothly and how other trucks would bounce people around. I told him "I appreciate that, and its a fine truck, but off-road its all about the line you pick". 2WD or 4WD, practice and be smooth. Use the 4WD as the protective factor, thats my motto.
Traveler III
Something that hasn't been mentioned, though, is the traction advantage of FWD - having weight constantly over the drive wheels. I suppose I have the best of both worlds with the CRV - FWD most of the time until RT4WD engages, then 4wd while it's needed, AND near perfect weight distribution (53/47 front rear). The very slight bias to the front means when you load your gear in the back, you're pushing closer to 50/50. It's a remarkably well thought out vehicle where all the different aspects of its design all seem to work in beautiful harmony.
Pathfinder I
This is one of the reasons I bought my first Canyon instead of a Colorado in 2016. The Canyons came equipped with AutoTrac auto 4wd which will drive in 2wd then switch to "4wd" when slip is detected. The Colorado up until 2017 didn't offer it. The feature came in handy during winter when our winding, hilly roads in the neighborhood turn slick. The Duratracs on the rear of the truck were crap in terms of lateral grip (on wet roads) so it was very easy to accidently induce oversteer while in 2wd on a twisting road. So when my fiance' drove the truck in bad weather I told her leave it in Auto4wd and drive like normal. Pretty amazing how much of a difference 4wd/AWD can make in such situations. Especially driving the same turns back to back with and without 4wd. She had been driving a 2011 Outback for years so she wasn't aware how screwy a light rear end pickup truck handles in the rain/snow. She now has a '17 CRV AWD and I just put Geolandar AT G015s on it in case we get lots of snow this year.
