I still feel this is just a form of post hoc definition of AWD. When the Range Rover came out in 1974 there was no such thing as an AWD. It was a 4WD. Another example is the Ferguson four wheel drive system. They never called it AWD, it was always 4WD. Even when there was a brief flirtation with 4WD in Formula 1. JLR are guilty of revising history here.
AWD versus 4WD just doesn’t make any useful sense. Restricting 4WD to be the class of agricultural designs where the only option is to fully lock the centre drive, and thus only operatable in traction limited conditions is very limiting, and needlessly confusing.
Looking about there is a huge amount of contradicting terminology. Toyota seem to say that the difference between their AWD and 4WD vehicles is that the 4WD systems allow for right to left torque control in addition to front back, whereas AWD only allow for front to back. Yet there are others that define AWD as designs with torque vectoring, and 4WD as ones without. It is just a silly mess.
Advances in tech make a huge amount of this impossible. Most people seem to regard AWD as a design set up for road/highway and 4WD as systems more directed at off road traction limited. The habit of attempting to show horn rear wheel drive into a transverse engined FWD platform makes for some very dopey designs, and really, they just shouldn’t bother.
50-ish years ago the distinction between traditional 4WD and new-fangled AWD was clear. Nowadays “4WD” is darn near a legacy automotive term right up there with “carburetor”, “choke”, and “spark advance”.
Any given motorhead with a collection of vintage vehicles is welcome to use the traditional terms applied to the traditional distinctions of traditional designs.
But to assert that today there is a bright line well-agreed distinction is to fly in the face of both modern marketing and modern engineering. We may as well be discussing the flower code (wiki) so beloved of 1800s etiquette mavens. A traditionalist motorhead may well know what they think they’re saying, but pretty much nobody else is hearing what they think.
I’ve noticed in SUVs from around a decade or so ago…specifically, the Oldsmobile Bravada and the Mercury Mountaineer…the Limited Slip in the center differential/transfer case was so tight, turning the steering wheel more than 90 degrees makes the tires bind up to the point that at idle speed the car stops altogether.
Just to confuse things further, I have 2019 4-Runner. The Off road model. The center differential locks in 4 wheel drive (front to rear). High range or low range.
I can hit a button to lock the rear differential as well (right to left on rear wheels only). But I can only lock the rear differential when the 4x4 system is in low range. You’re pretty much limited to below 20 mph, which is a good thing. You had best need it to do that.
It has another switch to turn on limited slip for all wheels (the brakes control that). You can not have the rear differential locked in when that is on for reasons. It’s only for low range as well, but works freaking fantastic in deep snow. A previous Nissan Pathfinder had something like that, but it was lacking for sure.
Going from high 4x4 to 2wd and back is still a lever that you manually engage. You can do it at pretty much any speed. So it’s nice to be able to pop it into or out of 4x4. I drive from nasty snow conditions to dry roads all the time on the same trip.
Tacoma has a dial to put it in 4 high. To put it in 4 low you have to shift to neutral first, NOT park. It’s not very clear you have to do it if you’ve never done it.
Does the 4Runner have crawl mode? It’s nice, but loud.
My wife has a 2010 RAV4. It has a 4WD button. Apparently, it only works below 25 mph, and shuts off if you press the brakes. I disagree that the limits are useful. I much prefer the 2WD-4WD(H)-N-4WD(L) lever on my '99 Cherokee. When it’s in 4WD, it stays in 4WD.
Maybe I wasn’t clear Johnny. LOW RANGE 4x4 is only good to about 20 mph. That’s about as fast as you can physically go in low range. That’s because of the gearing. Low range is for off road jeeping. But you know that.
And so, the locking rear differential is only used for when you’re in a tough spot, or stuck. In that situation, your probably going to drop into low range anyway. You really don’t want to have your rear differential locked at speed, even on the snow. Having the 4x4 center dif locked in is not really an issue on snow. It can cause a little slip in tight corners though. I go through switch backs daily, and it’s not an issue. Again, you should be on snow so your tires can slip a little bit.
I use regular hi-range 4x4 on snow covered highways all the time. Also if you put the 4-Runner in 4x4 hi or low, it stays there.
If that’s really the way your wifes Rav 4 works, that’s just stupid. And it shuts off if you put on the brakes? What? That’s insane. Sounds like something is wrong with it.
There’s now ‘low range’; just a button on the dashboard. I agree that 4WD(L) is for special situations. I’ve rarely used 4WD(L) in the Jeep when not offroad (and only occasionally offroad). I keep the Jeep in 4WD(H) when I’m in snow. I leave it engaged when roads are partially clear, but listen and feel for binding. Once I’m on somewhat dry or not very slippery pavement, I shift into 2WD.
But with the RAV4, you just have to trust its anti-slip system. You can push the button on the dash, and it may or may not do something. Since I don’t know how to tell it, ‘Look. The road is covered with snow. I want to lock in 4WD and keep it there until I’m ready to disengage,’ I prefer the control of having a lever with a solid ‘clunk’ when I use it.
[Moderating]
Just linking to a page of Google results, or telling someone that the answer is Googleable, is not an acceptable answer in FQ. Everyone knows that everything can be Googled. If someone comes here with a question, it’s because they want a better answer than that.
Yes, there is no low range. Only a button. On our trip, I pressed the button and the 4WD locked light came on. And when I’d look at it again, it was out. After we got home, I googled it and found out that the 4WD lock only works below 25 mph and turns off if yo apply the brakes. I agree that that is crazy. I want to decide when I want to use 4WD.
I know the Cherokee Johnny. The county I work for used them for building inspection vehicles and also vehicles that appraisers drove around. Well, any department really.
On my first day of work, back in 1992, they really didn’t have any training for me. I was asked if I could drive a manual transmission, “well of course”. I was told to go grab a vehicle, some maps and drive around and get to know the county.
I smiled the entire time knowing I would LOVE this job. I’m still at it, 30 years later.
I bought the 4-Runner because it’s one of the last 4x4’s out there.
