Hello, everyone and [welcome] we are inside the
2017 Nissan Frontier
Pro-4x, [and] we're going to be doing some testing to [show] the differences between two wheel drive for high and for low now the [pro]
[4x] adds some off-Road titties to the base frontier, and you know before we get into these tests
We're going to go to a little whiteboard session and talk about how this all-wheel drive system is well suited for off-Road conditions
Here we have a drawing of what [the] four-wheel drive system on the frontier
Pro-4x looks like and it's kind of expanded out so we can see [all] the components
So you've got the engine that of course sends power the transmission that [will] then go to a high or low gear
Reduction and then this is everything in blue here is the transfer case. So there's a chain connecting
What will eventually be [the] output shaft for the rear differential?
Connecting to the output shaft for the front differential
And so there you [can] see [that] and typically with part-time four-wheel drive systems
Systems where you can switch from two-wheel drive to four-Wheel drive?
You're not going to have any slip within this transfer case these can be gear or chain driven chain tends to be more common these?
Days and in the rear you've got an electronic locking
Differential and then up front you have an open differential now nissan also employs what they call active brake limited slip on all four
wheels so if you have this rear
Differential open and you start have [slip] on one of them
it will break that tire to send power to send more torque to
The other tire which does have grip of course if you have it locked. There's no need for that
It will automatically do that, and then on the front axle of course having that open [will] be useful there
And so I've got two different scenarios to kind of talk about you know
What will this all-wheel drive system be doing and why is the beneficial for offroad so our first scenario?
We have one tire without traction, so we could say for example that this tire is up in the air
It's on some ice but worst case. Let's just say it's up in the air
So you may think alright well because this is an open differential up front and that [tire] is in the air
It's simply going to Spin, but it actually can't because if you lock this air
Which is what this transfer case will be doing and you lock the rear now
You've locked these two speeds together, so if this tire is going to spin it requires rotating this shaft
And if this shaft is rotating it requires rotating this shaft
And if this is rotating it means both of these are rotating so in order for that [to] spin
Both of the rear Tires also have to spin and because they have traction this won't spin and you'll simply move on no issues
Let's move on to a kind of worst case scenario something much worse than that
Let's say you have three tires in the air or three tires on ice because three tires in the air isn't really realistic
But you get the idea it is
Possible if you have those three times in the air that all three of those could spin because these are linked this is open
so it's going to allow for a speed differential here, but this will rotate at the same speed as these and
So it's possible that you have all three of those rotating together, then of course you do have that 4 wheel
abs
so you can brake that front left tire and that prevents everything from spinning and then as a result it gives more torque to the
Wheel which is on the ground and you accelerate?
Forward so you know when you do have a [lock] center in the locked rear it really does open up
The possibilities as far as you know there there are very few circumstances
In which you know obviously this has got three times in the air
And you're still gonna be able to send torque to that wheel so very few scenarios where it isn't effective
so now we'll head back into the car and do some acceleration testing and show the differences between
Accelerating with just the rear with all four and then if you put it into that low gear range okay, so the first test
I'm going to run is two wheel drive
[so] there's going to be the rear tires only and
it's going to have traction control off and the way I'm going to do it is just lift my foot from the brake and
Mash it on the accelerator pedal now
You'll get a better start if you hold your foot on the brake and the accelerator pedal and let off the brake
[but] I don't want to do that because I don't want to do it in for low where you have a huge torque advantage and
Could potentially cause problems that's not something you'd want [to] do you don't want to launch and for low with your foot on the gas
And the brakes so we're going to do everyone the same start with the foot on the left pedal move over to the right pedal
And [just] floor it and let the traction control, sort it out
This one won't have traction control on we'll see if there's wheel slip start of our first desk traction control off two wheel drive
and there was no wheel slip with
Traction control off so I don't [expect] that to be much different with traction control [on] we'll go ahead and turn [around]
And do it again with traction control on so that was a zero to thirty time of 3.5 seconds
Okay, traction control is on two wheel drive
And once again we have a zero [2:30] time of
3.5 seconds so as I expected because there wasn't any wheel slip it was actually the same time with traction control on and off just
flooring it just not enough torque to
Really get things spinning now
we'll go ahead and try [it] in [four-wheel] drive high and
You know because there's no slip
You you probably won't expect to see much difference there because four-wheel drive isn't really going to add any additional
traction since it's not [slipping] in
two-Wheel drive
But we will see the gearing difference once we put it in
for low now
remember when you're doing this you don't want to put a part-time four-wheel drive vehicle in Four-Wheel drive on
pavement
the only reason I'm going to do it here is because I'm going in a straight line so all the wheels are traveling at the
Exact same speed, and it's [okay] to do and then once I get to the end of the run
I'm going to take it out [of] four-wheel drive so I can turn [around]
But basically you never want to use part time full
Four-Wheel drive on pavement because you'll have some binding in that all-wheel drive system
It doesn't allow for the difference in wheel speeds that you have while turning
3.6 seconds, so you know what's interesting about that is
Because you're going to have more power losses when putting it in
Four-Wheel drive versus just letting it do it in two-wheel drive
It looks like some of those losses
Actually materialized into a slower [zero] to 60 time or zero to 30 time not a huge difference three point five five seconds
versus three point four nine
With the traction control on and in Rear-Wheel drive
But still a difference nonetheless, so you have less power at the wheels when you're in four-wheel drive
[but] [you] have more grip so if this car had more power
You would see a better acceleration time because it doesn't have more power and because it won't slip in two-wheel drive
You actually don't see that you see the opposite, and you see a slower zero to [thirty] time in four-wheel drive now
Finally we'll put it in for low, and this will give [us] an advantage in gearing so hopefully we'll see a quicker time
Put it in neutral
over to four high
Put it in for low
traction control automatically goes off back into drive
Pull up to our starting line
And start our test
It feels quicker. You definitely feel the gearing advantage and yep it was quicker 3.2 seconds
So better than our two wheel drive version
By about a quarter of a second and you know better than our four wheel drive version in for height so cool to actually see
The differences in gearing there and see you know based on which drive mode you're in how much acceleration
You're going to have [whatever] this is always going to be traction limited, so in Four-wheel drive
You will have an advantage when there isn't good traction. This is done on a road, so there's great traction
So thank you guys for watching and if you have any questions, or comments feel free to leave them below