Hello, everyone and welcome in this video
We're going to be talking about the Ford Raptors Clever ability to switch between two wheel drive all wheel drive and four
Wheel drive. Now you may be wondering,
"What is the difference between all-wheel drive and four-wheel drive?" and
Generally what this means is all-wheel drive vehicles, the front drive shaft and the rear drive shaft will be able to operate at different speeds
versus four-wheel drive
Which is a selectable mode locks these two axles
Meaning that the front drive shaft and the rear drive shaft are both going to be rotating at the same speed. Now all wheel drive
Vehicles because they allow for a speed differential can drive on pavement versus four-wheel drive vehicles shouldn't drive on pavement if both of these
Drive Shafts are locked and rotating at the same speed because as you go around tight Corners
It will cause binding within the system. So as far as the Ford Raptor the first thing
We're going to do is look at a general overview of the four-wheel drive system,
Then kind of deep dive into the transfer case and talk about the different driving modes
Which exist. So starting with the overview: you've got your engine,
This is of course not to scale you're not gonna have this massive one drive shaft on one side
And then it's super tiny half shaft on the other. Not to scale, but point is you can kind of get what's going on.
You've got your engine sending power to a transmission,
That's sending power to the transfer case that splits power between the front and the rear. They actually do have an optional
torsen front differential limited slip Diff and then a locking rear axle.
So really good all-wheel drive system
and then you do have
Disconnecting hubs up front for operating in that two-wheel drive mode. So now let's look inside this transfer case at what's going on first
We'll kind of look at the different components, and then talk about how it works in the different drive modes.
So you've got your engine power coming from the transmission in here that's sending that through a reduction gear
So whether you're in for high or for low which is switched using this range selector right here?
Power continues along this shaft to the four-wheel drive, Selector. So that will put you in for high or for low that just basically
Combines these two shafts so that they now rotate at the same speed this chain is connected to both this shaft and the shaft
So if you lock them together both of these will rotate together
Then you have a wet multi-plate clutch which is connected between this shaft right here, and this chain right here
That is your drivetrain so able to drive the front drive shaft then in the middle here
You've got this selector shaft which kind of has this you know slanted profile to it
So it's basically a cylinder you have an electric motor that will rotate that cylinder and as that cylinder rotates it will force these
Selector Forks into certain positions allowing for you to choose between four high for low or
neutral if you are towing the vehicle and then selecting into four wheel drive or
Disconnecting from that four wheel drive, and there's of course return Springs that force these back into position
Depending on how this rotates so our first scenario
Driving in too high just driving those two rear wheels you're going to have the front hubs disconnected, so you're going to be sending power
Just basically straight across to the rear wheels this clutch pack will be spinning, but it's not locked up, so you don't have
This spinning all that much it will still receive some torque because you do have that wet multi-plate clutch in there
So you've got you know that Viscous fluid that oil in there so as it rotates it will transfer some torque
But again, you're not connected to those front wheels
Those half shafts may be rotating as you can see in this little clip right here
But the wheels are actually disconnected from those half Shafts
So they're not receiving any torque from the engine even if those half Shafts are rotating
That's just a result of you know the the friction within this clutch pack just from that viscous fluid floating around in there
Not locked up again once it's in that two-wheel drive mode
It's completely you know
disconnected as much as it can be so very little torque is actually passing through it and all of that torque is going to your
two rear wheels
Now once you put it into for auto what it's going to do is connect those front hubs
So now your wheels can be driven on the front and it's going to start to lock up this clutch pack when needed so in
Scenarios you know where you have slipper where you're not basically in a steady state
It's going to apply pressure to this clutch pack so that now you're connecting this drive shaft and this drive shaft
through this clutch pack through this chain
And so you know the more pressure you apply?
Obviously the more lockup you get but because it's all going through this clutch pack and not you know a locked chain it does allow
for slip
so the advantage of
Is that you can use this on road you can drive in the wet in the snow things like that on pavement
And you won't have binding of your axles because you do allow for slip within that clutch pack and in Steady-state
Scenarios let's say you're just cruising along the highway at 65 miles an hour
it can disconnect that so you're really only just sending most power to
Those rear wheels and you know saving a little bit of energy you don't need to send it to all four wheels in
Scenarios like that so in steady state it can disconnect when you need it it can lock up and act as an all-wheel drive system
You know traditional all-wheel drive system out there and allow you to drive on the road and still power all four wheels so a very
Cool mode now if you go off-road you're gonna of course want to put it into four-Wheel drive
And so this means you know you'll let the slip occur at your wheels rather than within the drivetrain
And that's why you should only do it offroad because otherwise you'll bind up this system, and you can cause damage
So when you select four-Wheel drive
you know this will rotate this electric modal will force this selector to push that fork in and connect this shaft with the
Front drive Shaft Via this chain, so it'll force that collar in that will be connected and now you're locking these two speeds
So always these two are gonna rotate at the same speed send that power to the front and rear differentials
And then you know if you want for low of course you select that with this range selector here
And that's just a gearing difference
So more aggressive gearing allows you to crawl allows you to put more torque down now on the steering wheel there's actually a drive mode
Selector and this will choose the optimal setting for the four-wheel drive, or all-wheel drive system for you
So you've got normal and sport which will basically just leave it in two-wheel drive mode you've got weather which will put it in for
Auto so you know if it's raining things like that if it's snowing it will you know choose to send more power to the front?
Axle when it needs it you've got mutton sand which will put it in four-wheel drive
Bah-Ha and then rock crawl which will put it in for low
So you can crawl and not have any slip and and have a good amount of torque when you are driving up in Super-slow speed
sinners
And get that benefit of the gear reduction so a very cool four-wheel drive setup that ford has incorporated
Within this truck not to mention the fact that it has 450 horsepower
510 Pound-feet, so a very fun truck to very cool all-wheel drive four-wheel drive combination system
Thank you guys for watching if you have any questions or comments feel free to leave them below
you