4WD Low vs 4WD High | What is the Difference?
As you guys can see, we are in four wheel, drive high, that wheel and that wheel are spinning. This wheel is spinning . What is going on today, guys my name is alex. Welcome back to the channel. Today we are talking about four-wheel drive low.
What it is, how to use it when to use it and some common myths with four-wheel drive low, my favorite so stay tuned for that. So if you guys are following the channel, you know, i’ve talked about four wheel, drive low here and there in the past, but i figured i would dedicate a single video going over exactly what four wheel drive low is and uh. Well. This is my 2022 ram. 2500 power wagon beautiful truck – and it is a perfect truck for all of these demonstrations because it has basically every off-road component.
You could want on a truck, so most trucks come with four-wheel, drive, high and four wheel. Drive low four wheel. Drive high is using the same gear ratio as two wheel drive and simply splitting the power 50 50. In the transfer case driving your front drive shaft, i figured most of you guys know that four wheel drive high is used for well driving at higher speeds like on a snow covered road when you’re going above 30 40 kilometers an hour. So this is your transfer case right here, and this transfer case has two functions.
First, function is going from two wheel drive to four wheel drive and the second function is going from high range to low range. Now that gives us a total of four options. So two wheel, drive high two wheel: drive low four wheel, drive high and four wheel drive low now most trucks, if not all trucks, don’t have the option of two wheel drive low. However, that is 100 possible with basically any transfer case and most manufacturers just don’t give you that option because well, i feel like they just think it’s not really that useful and two-wheel drive low. I don’t think it would get much use anyways.
However, it is a possibility now we know the transfer case, splits the power of 50 50 from front and rear in four-wheel drive. We also know what it’s like driving at high range. You do it probably 95 of the time, so that leaves us with low range. What the hell is going on with the low range in the transfer case, so going into low range in the transfer case, simply just changes. The final drive ratio of the vehicle so, for example, this transfer case in this power wagon has a low range of 2.to 1, meaning if in high range, the final drive ratio in first gear, let’s say, is around 20 to 1
If we go into low range and either two-wheel drive, low or four-wheel drive low, most likely, the final drive ratio will now become 50 to one now. The final drive ratio of vehicle basically just means how many times the wheel is spinning in comparison to the engine or the crankshaft. So if you have a final drive ratio of one to one which most vehicles do usually when you’re traveling around highway speeds, what that means is for every one wheel, rotation, the engine or the crankshaft is also rotating one time. Hence one to one now doing the math a 50 to 1 final drive ratio means that this tire is turning once while the crankshaft is turning 50 times in that one tire rotation. Now a higher final drive ratio is great for one reason, because it delivers more torque, so torque and wheel speed are proportional to one another.
So, like i said with this power wagon, our transfer case is 2.6 to 1. That’S the ratio between high range and low range, so if we were to put it in low range, this wheel would spin 2.6 times slower. However, we would have an increase at this wheel of 2
6 times the torque, so in a very simplistic way, that is what low range does it simply just increases the final drive ratio of a vehicle.
We can also think of low range as simply just a gear change, so going from. Let’S say third gear to first gear is essentially doing the same thing as going from four wheel: drive high to four wheel, drive low you’re, just changing the final gear ratio and bumping up your torque as well as lowering wheel speed. So a perfect example is my bike here. So, as we can see, the wheel is turning quite fast in comparison to the crank here, um and well at first it was pretty difficult to get it going. So if we stop the wheel now, we’ve dropped the gearing here and for our example, we’ll call this low range for the bike and, as you guys can see, it’s a lot easier to turn.
The pedals and the wheel turns a lot slower in comparison to the crank. This is because this gearing produces a lot more torque, and it makes a lot easier to pedal now. I use this example with this bike because i think everyone can relate to biking up a hill and when you’re in a higher gear, you need a lot more torque turn those pedals. But what do you do you gear down and therefore allowing you to turn those pedals much easier? However, you also lose wheel speed.
Hence why torque and wheel speed are proportional to one another. So why do people always say four wheel? Drive low is awesome for off-road. Well, for starters, like we’ve established your wheel, speed is dramatically decreased and that allows a lot more control of your wheels in an off-road situation. Now, with less wheel, speed comes the increased torque, and that is the number one factor why four-wheel drive low is very good for off-road.
Let’S say you’re going up, i don’t know a steep grade. A bumpy hill torque allows these wheels to just keep on climbing without having to you know, put a lot of engine power into these wheels, potentially causing them to slip. This gives you maximum traction, and that is why four-wheel drive low is usually the best option for any off-road situation. It also allows you to feel a lot more control of the vehicle. It feels a lot more like you’re crawling over obstacles versus spinning, and you know high revs and in most off-road situations you really don’t want any wheel slippage um, once a wheel starts to slide, the coefficient of friction actually goes down.
The highest coefficient of friction is a static movement, so, basically, when the wheel is not spinning, you have the highest coefficient of friction, and that is why you get the most traction with four wheel drive low and in general you really don’t want to spin your wheels Too much when you’re off-road, because you know there could be sharp rocks a river crossing last thing you want is to be spinning those wheels on those slippery rocks and losing traction. So four wheel, drive low is just really good for those types of situations. However, now that we’re on that topic, there are some situations where you do want some wheel. Speed snow is one of those situations because well snow is very slippery. So, yes, four wheel, drive low is going to give you some added torque.
However, that torque can’t really be delivered on such a slippery surface like snow, so the wheels are more likely going to slide in four wheel, drive low in theory, so in situations like that, it may be more beneficial to have that um, higher wheel, speed and stay In four wheel, drive high and just kind of power through the snow, a similar argument could be made for sand or mud, but once again i think that would depend on the situation in general. Four-Wheel drive low is going to give you the best traction and the best chance and the best off-road experience in most situations. All right now, the fun part we’re going to talk about some four-wheel drive low myths. So i do see a few comments. Every now and again talking about uh four-wheel drive low, so i thought i would highlight some myths that i’ve heard over the years so myth number one all of my wheels lock up when i’m in four-wheel drive low.
Unfortunately, that is just not the case. Like we’ve mentioned this, video four wheel, drive low is just a speed range um. It has nothing to do with how the drive line actually delivers power to your wheels. That happens downstream from the transfer case. All the transfer case does.
Is it just splits the engine power 50 50 between the front axle and the rear axle, after that? It’S up to your differentials to decide which wheels get power. So if all four wheels, don’t lock up in four wheel, drive high they’re, also not going to lock up in four wheel, drive low and we’ll use our beautiful service truck for an example here, all right, so the rear end is fully off the ground. Unfortunately, there’s actually a pause in this truck, which, who would have guessed so both wheels, are going to have to be off the ground. This front wheel is off the ground.
However, our front passenger side is on the ground, so we’ll start in four wheel drive high. Those three wheels should all spin and in four wheel drive low. Only those three wheels should spin because the drive line is not going to lock up all four wheels in four wheel drive low. We are in four wheel drive, let’s see what happens so, just as i predicted one two [ Music, ] and three wheels are spinning because we have the posi back there, but our fourth wheel is just stationary. So sorry, it’s pretty dark here.
We will shift to four-wheel, drive, low four-wheel, drive, low engaged and we will see if we’re gon na fall off the jacks here and there we go. We have not fallen off the jacks yet now, as you guys can see, we got one two three and four. Our fourth wheel is not spinning whatsoever, because four wheel drive low, does not lock up the drive line completely so, as you guys saw not all four wheels lock up in four wheel, drive low the same amount of wheels spun in four wheel, drive high and four Wheel, drive low all right myth number two that i hear quite often is that in four wheel drive low, my front axle my front differential locks up and again that is just not true. I imagine most trucks that people own these days are pretty much all electronically. Actuated um or activated four-wheel drive systems and when you electronically activate four-wheel, drive low.
That goes to your transfer case. There’S no wiring connection to your differentials. So this is my transfer case and you guys can see the wires going into it. So those wires are going to tell the transfer case whether it be in four wheel, drive low forward, drive high and so on, um, and that makes sense. However, if you don’t have wires going to your differentials, which is a completely mechanical system, there’s just no magical component – that all of a sudden locks it in four-wheel, drive low versus four-wheel drive high, like we’ve kind of mentioned earlier in the video um four-wheel drive low, Stops in the transfer case, it has no input what happens down this drive shaft or what happens down this drive shaft and how the power is split between the two wheels that is purely a mechanical differential operation has nothing to do with the transfer case or what Range you’re in now, this truck being a power wagon has the awesome thing of a front differential locker and, as you guys can see, there is the wire going into the differential to electronically lock it now.
Some trucks will have what’s called a center axle disconnect right here and that just simply disconnects the axle from the passenger side wheel. It has nothing to do with differential, so don’t be mistaken when you see wires going to your center axle disconnect coming to my rear differential, we have a locker in this differential as well and, as you guys can see, that is the wire going into the differential To tell it to lock, so if we think of power going downstream, you start with the engine, goes to the transmission. Comes to your transfer case. That’S when four wheel drive low is selected and then the power goes down. These two drive shafts.
So if you have an open differential downstream from where four wheel drive low affects the drive line, if you have an open differential, it’s going to stay in open differential and four-wheel drive low. So, in terms of your front differential locking up in four-wheel drive low. That’S just simply not the case, and unfortunately, it’s very rare for a truck to come with a front locking differential. Like i mentioned, the power wagon does because well it’s just a very off-road focus truck. In fact, if you have a 3rd gen or 4th gen ram 1500, not a single one of those trucks came from factory with a locking differential, wasn’t even an option.
So unless you’ve installed a front locker yourself or someone else has you’re just not going to have a front locking differential, unfortunately, so i’ll do the same thing. With my power wagon i’ll put the wheels up in the air i’ll put it in four-wheel, drive low and you’ll see that the front differential when it’s unlocked, never never locks in four wheel, drive low. So we will put this in four wheel drive high there. We go, we are in four wheel, drive high right now, let’s put her into drive, as you guys can see, we are in four wheel, drive high that wheel and that wheel are spinning. This wheel is spinning.
However, this wheel is not so, let’s see what happens with four wheel drive low all right, so we are in four wheel: drive low, so we can see in four wheel, drive low once again, one two wheel, spinning this wheel is spinning, but not A big surprise, this wheel is not spinning in four wheel: drive low, so there you go guys four wheel, drive low, does not lock up the front axle, no matter what, and i hope that makes sense. I hope that shines. A light on four-wheel drive low how it works and kind of how to use it. It is definitely better off-road. Maybe that’s where some of these myths come into play where uh people think all four wheels lock up just because it is going to give you better traction.
Maybe it feels like all four wheels are locking up because you get better traction. However, it’s just really not the case and there’s really nothing that magical about four wheel drive low. It’S simply just another speed range and at the end of the day, all it does is just increase. Your final drive ratio, which slows your wheels and delivers more torque at the same time. So i’m going to get to rotating my tires as this truck’s pretty much jacked up should be pretty easy, but as always, if you like, the video, don’t forget to leave that thumbs up and if you like, cool stuff, like this.
