Toys4RJill

Thought I would just make a separate thread for those who want to discuss. For those who want to talk shop with me....

The V6 4Runner from 03-09 was a multi-mode system. 2WD/4WD is 4HI and 4LO. The V8 4Runner was a full-time system....4HI was permanently engaged, open center differential that could lock...also offered 4LO




Every Land Cruiser from 1990 (I think) and every single Lexus GX or LX ever imported to the US were full-4WD systems. (super rare to find SUVs with this set up)....Toyota has done it for most of their BOF SUVS for a very long while.

If anyone really cares about wanting the ultimate four-wheel drive set up. You want full time four-wheel drive with a hand operated 4LO lever. Also of excellent mention is Toyota 4Runner TRD Pro with a hand lever shifter that goes from 2WD - 4WD by hand operation, but it is not full time.

Another good set up would be the Jeep Wrangler. I think you can get the Jeep with full-time 4WD.

mmarshall

First, before we go on, let's define the terms a little more closely, so we can separate apples from oranges.

AWD (all-wheel-drive) is a center-differential system, found on most Subarus and a lot of other passenger cars and smaller crossovers, that powers all four wheels all of the time, can be used on both wet and dry surfaces, and, through the center differential, splits the torque front/rear as programmed by the engineers....and, in some cases, varies the split according to driving conditions and the desired handling/driving feel. Most examples, although there are some exceptions, do not have a locking differential for really serious traction conditions. Nor is there a Low Range for serious off-roading. And most do NOT have a two-wheel drive option, with a switch, that disconnects two of the drive wheels for better gas mileage and better performance, though the late Suzuki SX-4 hatchback was an exception. And the latest Audi Quattro system is different from previous Quattro systems....it now runs mostly in 2WD unless wheel-slip is detected, and then shifts it to the other two wheels as well.

"Full-Time" 4WD shares some of the attributes of AWD, including a center-differential for dry-pavement use, but also usually includes a Low Range for off-roading. It also (usually), if the 4WD is not needed, includes a 2WD option that allows better gas mileage and acceleration. The system will typically have a three or four-position switch marked with at least wth 2Hi, 4Hi, and 4Low. This system has become almost ubiquitous on most (not all) newer pickup trucks and the most popular of today's mid-size and larger SUVs. (not the smaller CUVs, which usually have AWD).

"4WD on-Demand" systems do generally what the name implies...like Audi's newer Quattro systems, they power two wheels until slip is detected, then, when extra traction is needed, shift the torque, through a center differential, to all four wheels.

"Part-Time" 4WD is an old and unsophisticated system that has been phased out of most modern vehicles, although it may (?) still be found on some versions of the Jeep Wrangler and pickup trucks of older design. It usually has a Low range and a manually-shifted transfer case, but no center differential, and locks both front and rear axles together so that all four wheels rotate at the same speed and allows no slip. It is simple, durable, and well-suited for hard-core off-roading...but usually cannot be used on dry pavement (disclaimers warn of this) because it causes tire/driveline problems, and sometimes damage, when going around dry curves.

Then, on top of this, you have specialized and sophisticated systems, like in the Range Rovers and other very expensive SUVs, where you have a number of different snow/ice/mud/tow-haul/sand/gravel, etc....modes, but they usually just use a computer to fine-tune the existing Full-Time 4WD system into different specialized driving conditions.

Toys4RJill

Full time 4WD does not have a 2WD mode. Therefore, a 4Runner Limited, Land Cruiser, LX570 or GX are never in 2WD,..EVER.

What you are describing above would be Toyota 4WD with multi-mode selection. Sequoia has a multi-mode whereas the Land Cruiser has full time with no-multi-mode.

mmarshall

Like I said, some do and some don't. If it has a switch with 2Hi on it, it does have the 2WD option.....even though you can keep it in full-time 4WD if you want. If it does not have the 2WD option on the switch, then, of course, you are correct. "Full-Time" 4WD simply means that the 4WD can be used anywhere, on any surface, if desired, without being concerned with the possible tire/driveline-damage of the part-time system on dry pavement..

Toys4RJill

Or like I said... always in 4WD....4HI was permanently engaged.....Therefore, a 4Runner Limited, Land Cruiser, LX570 or GX are never in 2WD,..EVER.

JDR76

I had a 4Runner SR5, and like Jill’s, there was no 2WD mode. I kind of wished it could go into 2WD to save a little gas, but no biggie. It was a very good, capable system.

Toys4RJill

I forget you had a 4Runner....Did you ever look at the V6 at the time? It had a hidden full 4WD mode, so the 4WD could be left in 4HI in all circumstances.

JDR76

Not really. I really wanted the V8 so I only looked at those.

Toys4RJill

That is cool.. It is too bad Toyota discontinued the V8

mmarshall

True, but other Full-Time systems do allow a 2WD option. That is why I said, earlier, one has to separate apples from oranges.

Here'a an example of what I'm talking about. The "Auto" position on the switch allows automatic 2WD/4WD operation as needed. The 4H is Full-Time AWD high mode.....the 4LO, the Low-Range transfer-case.

Toys4RJill

What SUV is that from?

Toys4RJill

But this thread was just about Toyota full-time 4WD.

Stroock639

oh yea only full time 4wd on the V8 models

Toys4RJill

Technically, at the time, V8 4Runner was available as a 2WD only variant. But full time was the only way to 4WD on the V8

mmarshall

OK, if you prefer to keep it about Toyota, fine. I thought you were referring to Toyota's systems vs. those of other manufacturers.