Almost nothing in this article is accurate. AWD vs 4WD has nothing to do with locking front and rear differentials. It is that one has a transfer case, and the other does not. Most 4WD vehicles have open front and rear differentials.
The National Park Service doesn’t require locking differentials, so I’m not sure where this person got that idea from. They do however require that they have a transfer case, which the Cybertruck and Rivian do not. So despite the author claiming those would be 4WD, they are not. And do not qualify by the definition used by the NPS.
I think they are correct that there may be a need to update the rules since EVs have no need for a transfer case since there is no mechanical connection between the front and rear axles typically. It’s terrible to try and make that argument with all of your other information incorrect however.
Thank you for this, I was part way through and questioning my sanity.
Though now I’m thoroughly confused as to where my Audi Q7 Quattro stands in the grand scheme of things…
Apparently AWD:
Generally if there is a question of AWD vs 4WD, the only thing you need to look for as an ability to shift to 4 low. It changes the final drive ratio so all of your gearing is dramatically lower. It’s a capability that requires having a transfer case. Though I’m sure there are some weird exceptions out there of 4WD vehicles that don’t have 4 low, it’s a pretty simple rule of thumb to decide which side a vehicle falls on.
It’s possible to have an AWD vehicle that has a clutch or some other way to disengage two of the drive wheels. So you can have a selectable RWD or AWD. This is different than how a transfer case works though, and does not allow a change in final drive ratio.
AWD vs 4WD has nothing to do with locking front and rear differentials. It is that one has a transfer case, and the other does not.
That’s not correct either. The only difference is that 4WD allowes you to switch to 2WD and AWD does not.
That’s not true though. There are plenty of AWD vehicles that can swap between driving all of driving two. And there are plenty of examples of 4wd vehicles that drive all 4 full time. The humvee is a perfect example of a full time 4wd. It cannot switch to 2wd unless you remove a driveline. What it does have is a 2 speed transfer case that allows switching from 4 hi to 4 lo.
That’s not true though.
I’d love to see something other than you just saying no to back up your argument. Because just repeating wrong information doesn’t make you any more right. I didn’t even have to really look hard for sources that mention a transfer case as a key component of a 4wd system. And I’d say all of these folks probably know more than you.
https://www.edmunds.com/car-buying/awd-vs-4wd-whats-the-difference-and-which-to-choose.html
https://www.carmax.com/articles/awd-vs-4wd-which-to-choose
https://www.motortrend.com/features/4wd-vs-awd/
Oh, and on top of that, in the rules that this whole thread is about, they specifically mention the transfer case as the requirement for a system to be 4wd.
After researching it a bit, there doesn’t appear to be a definitive answer. None of the links you provided give one either.
Some claim AWD has a center diff. Some say it’s the manual vs. automatic control of drive wheels and diffs. Some say low range makes it 4WD. What some people/companies call a “center diff” could ALSO be considered a transfer case.
in the rules that this whole thread is about, they specifically mention the transfer case as the requirement for a system to be 4wd.
That article has zero cited rules, or really any citations whatsoever, so I’m not sure what you’re referring to.
Only thing I can say for certain is that the article claims 4WD = locking diffs, which is obviously not true.
In summary, I’m wrong but so are you so nanananabooboo
Edit: I was able to find this definition from NPS
What is the difference between a 4x4 and All Wheel Drive (AWD) vehicle?
True 4x4 vehicles have a ‘transfer case’ in the drivetrain that puts full engine power to the front wheels. All Wheel Drive, common on vehicles like crossover SUVs, relies on a ‘differential’ to send variable power to each wheel. AWD is good on level roadbeds in low traction conditions like snow. It is not designed to fully power the front tires in off-pavement rugged situations. For example, if the road goes up a steep hill and there is a lot of loose rock in the road, fully powered front wheels are needed to rotate strongly and pull the vehicle up the slope. AWD cannot do that very well and may fail.
This is the opposite of true. 4WD absolutely does not and cannot send all engine power to the front wheels and a AWD with center diff potentially can but probably wont. However they often do send a disproportionate amount of power to the front wheels, as necessary.
There is an answer and it’s the one I already gave. There are always edge cases and exceptions because there are an absurd number of variations and vehicles types. By and large I already gave the deciding definition, and it is in what I linked as well as many others places.
Edmunds - “Traditional 4WD systems have a two-speed transfer case with high- and low-range modes that can be selected by the driver, either with an electronic switch or a mechanical lever.”
CARMAX - “Key to how a 4x4 works is a piece of equipment called a transfer case. This connects the vehicle’s front and rear wheels, splitting the engine’s power evenly between them and making both axles turn at the same speed.”
And the article didn’t list the rules because it was wrong about everything. The rules are listed by the National Park Sevice. “A four wheel drive vehicle is defined as a sport utility vehicle (SUV) or truck with at least 15-inch tire rims and at least eight inches of clearance from the lowest point of the frame, body, suspension, or differential to the ground. Four wheel drive vehicles have a transfer case between the front and rear axles that locks the front and rear drive shafts together when four wheel drive is engaged. All wheel drive (AWD) vehicles do not meet this definition.”
So again, repeating yourself doesn’t make you more right. It does however increasingly make you look like an ignorant ass that has no desire to actually learn anything.
By and large I already gave the deciding definition
As I said, you gave one of many that don’t appear to have a common consensus or any authoritative source.
Edmunds - “Traditional 4WD systems
“Traditional” is the keyword there. Lots of AWD systems are driver-selectable.
Key to how a 4x4 works is a piece of equipment called a transfer case. This connects the vehicle’s front and rear wheels, splitting the engine’s power evenly between them and making both axles turn at the same speed.”
The center diff does the same thing, which is why I said earlier that it could be considered a “transfer case”, obviously with the addition of a differential.
And the article didn’t list the rules because it was wrong about everything.
Great, so we agree on that.
The rules are listed by the National Park Sevice
I edited my comment to include the NPS’ definition and explained how and why it’s incorrect.
Repeating yourself doesn’t make you more right. It does however increasingly make you look like an ignorant ass that has no desire to actually learn anything.
But, a four-wheel-drive system has locking differentials
This entire article is written based on a fundamental misunderstanding of AWD vs. 4WD and once again has nothing to do with EVs.
