4WD vs. AWD

[VicVictory]

Particularly with the eventual introduction of trucks and maybe SUV's, have we thought about the difference between AWD and 4WD?

4WD systems (particularly dual-range, such as those found on 80's M/T Subarus and a LOT of Jeeps) are absolutely gorgeous off-road, but not so great for reaction time in inclement weather and also horrible on dry roads should you accidentally (or ignorantly) engage them.

On the other hand, AWD systems (modern Subarus, Audis, just about every crossover SUV EVER regardless of make) are very tame when used on all road surfaces, but not as capable off-road as locked 4WD systems.

Proposal: further differentiate between part-time 4WD and full time 4WD (AWD) systems.

Give 4WD a slight boost in offroad rating but a significant hit in tameness (representing their harshness on regular roads when used improperly). Perhaps slightly better economy than AWD.
Give AWD a tameness boost but a modest reduction in offroad rating (yeah, they can go offroad, but they're most definitely not the preferred option because of shortcomings due to being designed for all-road use)

[maffc]

I'm not entirely sure but I think the new diffs in development might answer your points

[Daffyflyer]

Yes to all the things you said, basically

[vmo]

Basically, is the same (four wheel drive), but technically, exists differences.

[VicVictory]

Basically, is the same.

If you're saying that AWD and 4WD are "basically the same", then you don't understand the difference between them. Or the fact that AWD systems are often mislabeled as 4WD.

AWD systems are engaged either all the time (like a Subaru) or are controlled by a computer (like a Honda), and can be run on dry roads while engaged with no ill effects due to the use of variable power distribution and non-locking differentials. However, their offroad capability is poor compared to a true 4WD system. They are used primarily for additional grip and control on-road for winter. Most "full time 4WD" systems are actually more closely related to AWD than 4WD.

4WD systems must be run disengaged on dry roads because they lack power distribution and the proper differentials to prevent wheel bind. If you make turns on dry pavement with a 4WD system engaged, your wheels will bind. This causes tire, half shaft, and even drivetrain damage if it's done too often or fast enough. However, because of their design, which often includes dual-range gearboxes, 4WD systems are amazingly versatile both on winter roads and off-road, such as mud bogging or rock climbing.

[Daffyflyer]

*lots of things describing 4wd and AWD

Yes, exactly what you said is correct.

[Zabhawkin]

I hope that means that the differences will be implemented when the time comes. As well as the eventuality of a solid front axle.

[PMP1337]

Also, there should be 4wd way before there is AWD. Come on, I've seen the pick-up body but there isn't a 4WD to make a offroad pick-up. Also AWD drive systems should differ between FWD based AWD and RWD based AWD. Audi vs Lamborghini for example.

[WizzyThaMan]

I mean come on, why dont you show a little patience ?

[Killrob]

4WD will be available very early, if not right from the start, yes.

[BitTwiddler]

Well, I might get burned for this.

But AWD and 4WD do do the same thing. That is, provide each of the four wheels with drive power. Whether they do it some of the time, all the time, and where it was designed to work are completely seperate from the concept of driving all (of the four) wheels.

So I would like to request a drive train setting to allow you to configure how your four/all wheel drive works, rather then rely on the weak and often confused 4WD vs AWD terminology.

[Daffyflyer]

So I would like to request a drive train setting to allow you to configure how your four/all wheel drive works, rather then rely on the weak and often confused 4WD vs AWD terminology.

Bit too complex for what we want I think we'll most likely do the following.


Full time AWD (with a choice of diffs)
Selectable 4WD (with no centre diff, just a locking transfer case)

And maybe/probably: Part Time "On Demand" AWD (Honda Style, 2WD until it loses traction)

[BitTwiddler]

That's sort of what I meant. Such as "<Engine Type> AWD" setting in the platform, and some drivetrain setting that has the values like... Differential (then Diff setting), On Demand (then Diff setting), and Locking Transfer Case, per your example.

[RobtheFiend]

So I would like to request a drive train setting to allow you to configure how your four/all wheel drive works, rather then rely on the weak and often confused 4WD vs AWD terminology.

Bit too complex for what we want I think we'll most likely do the following.


Full time AWD (with a choice of diffs)
Selectable 4WD (with no centre diff, just a locking transfer case)

And maybe/probably: Part Time "On Demand" AWD (Honda Style, 2WD until it loses traction)

Isn't that what Haldex does? Wait until the front wheels rotate faster, THEN apply preasure to the middle diff, so the rear wheels start to drive.