By Michael Murguia – 11/30/16
Photos Credit: Barry J. Holmes
There is no doubt, lockers can transform even the mildly built rig into the equivalent of a mechanized off road tank, or if you prefer, “billy goat mode”.
While maneuvering and turning a vehicle, all four wheels want to have different turn rates. This is how a stock drivetrain is set up. Unfortunately, it allows all power to be transferred to the wheel with least resistance. If a tire comes off the ground or becomes “light”, it is going to spin while the other tires stop. You are stuck.
For the unindoctrinated, locking differentials are just that. They have many applications from drag strip racers, heavy equipment, and overland of road vehicles. If your “diff” is “locked”, it means both wheels on that axle are locked together and must turn at the same time. There are front, rear, and center lockers. In some vehicles (ehem FJ80), you have independent control of each locker.
Differential mechanics have been a part of automobiles since the beginning, and if you want bit of retrospective fun and a basic explanation of how differential systems work, this 1937 Chevrolet Motor Company film actually explains it nicely!
Do you NEED lockers for overlanding? Let’s look at three applications.
Headed to Ski-Mountain – Center Diff Lock
Lockers are not required in this scenario. Standard four wheel drive will do a great job at increasing traction. In this case you are on the freeway, on pavement and the road is probably slick, especially if it is icy-cold. You are probably going slower than the speed limit and want extra traction. In this case, the center diff lock will require your front and rear axles to receive the same amount of power, but all four wheels will still be independent, allowing them to turn at different rates while cornering. It provides added traction, without over-stressing the front and rear drivetrain, diff, and axels by locking those wheels on pavement.
Most four wheel drive systems lock the center differential when the vehicle is put into four wheel drive low range.
Baja – Rear Diff Lock
If you are in the sand, speed is king. You need to keep your speed up to keep from getting bogged down. With higher speed comes higher risk, and ideally you have visibility. In combination with airing down to 10 or 12 psi, speed and traction will get you through the soft stuff. Why rear? You will be going at speed and turning in tight radius, and you don’t want to grind and stress the front. axel in tight radius. Also, you are not pulling or crawling over rocks, and your front tires are really acting as rudders. Rudders with traction mind you, but rudders. We like to say, you need the room to “suggest” where the vehicle should go, because you are going to slide a bit, even at low speeds. Lastly, and perhaps in more extreme cases, locked rear wheels are used for steering under power, or “drifting”. On soft surfaces, you can steer your vehicle by applying power to the rear when locked. It will cause your rear end to “slide out” and point the nose where you want to go. This does not work if your front is pulling at the same rate.
Rubicon – Front and Rear Locks
Here is where the terrain is more technical. If you are in four low, your center diff is most likely locked automatically by your system. That means, you are choosing between your front and rear diff locks. In principle, your choice is dictated for you. If a front tire is spinning, lock the front diff. Front and rear lockers are especially effective pulling or pushing out of a cross-axle stuck. Cross axle means a front and rear tire is able to slip. With normal 4WD, you are stuck. By locking the front or rear, you will move forward as long as you have traction. So why would you have to ever go “fully locked”? Usually, locking one differential will move you forward, however, if traction characteristics change significantly as you are moving forward, like when crawling up a shale slope, or moving over a number of basketball-sized rocks, you may want to be fully locked. A steep dirt incline with a combination of soft and hard pack also responds very well to being fully locked, allowing you to crawl up a hill slowly instead of using speed to get up the hill.
So, Do you NEED Lockers for Overlanding?
Just looking at the examples above, in the first case, lockers are not required. It will provide increased traction in some cases, but standard 4WD goes a long way toward keeping your vehicle on the road. In the next two cases, though “normal” for some, they are pretty extreme cases for most who are engaged in vehicle dependent travel. Even if you are going through the jungle, you are going slow and may be using your winch regardless of how much traction you do or don’t have.
Before embarking on a journey, you need to evaluate the requirements of your trip. What will you be asking your vehicle to do? One of our core principles with Overland Bound is that is doesn’t matter what you drive, HOWEVER, your vehicle needs to be equipped and capable for what you are asking it to do. It needs to be safe. Even so, we can’t think of any case where a locker is required. Without a locker, it means you may be digging out or winching out instead of driving out, and that means your journey will be slower, but not required. Many people overland in rigs similar to the 2WD Westfalia Vanagons and live in their rigs doing so. Lockers not included.
You DO NOT need lockers for Overlanding
Great article, Michael! And especially enjoy the technical aspects of a drivetrain. Driving a Jeep GC with QuadraDrive II, I just flip a little lever and the computer decides whether to lock or not for me. As a novice, I like that, but I really like knowing what is happening!
As for needing lockers or not, I couldn't agree more! It's not a requirement. When I was a kid, I remember my dad saying "I can go anywhere a 4 wheel drive vehicle can go." While that statement might not be entirely true, I realized later that he was referring to skill as a driver and creativity in figuring out how to pass/get through challenging obstacles. This is the area I need work in — how to drive obstacles. I'd like to get to an OHV park to practice, but after reading someone saying they got held up behind someone that got stuck on an obstacle, well, I don't want to be "that guy!"
[QUOTE="Lassen10463, post: 55133, member: 4414"]Great article, Michael! And especially enjoy the technical aspects of a drivetrain. Driving a Jeep GC with QuadraDrive II, I just flip a little lever and the computer decides whether to lock or not for me. As a novice, I like that, but I really like knowing what is happening!
As for needing lockers or not, I couldn't agree more! It's not a requirement. When I was a kid, I remember my dad saying "I can go anywhere a 4 wheel drive vehicle can go." While that statement might not be entirely true, I realized later that he was referring to skill as a driver and creativity in figuring out how to pass/get through challenging obstacles. This is the area I need work in — how to drive obstacles. I'd like to get to an OHV park to practice, but after reading someone saying they got held up behind someone that got stuck on an obstacle, well, I don't want to be "that guy!"[/QUOTE]
If you happen to be in CA we are planning an OHV park get together in 2017 to go through some basic training! Thanks for reading!
I might tag along in 2017 if I can afford the trip.
[QUOTE="Michael, post: 55136, member: 1"]If you happen to be in CA we are planning an OHV park get together in 2017 to go through some basic training! Thanks for reading![/QUOTE]
That would be great! With enough notice I could make it. Any idea roughly when and where?
My jeep club has been doing this for a few years too. Safety clinic, hands on and practice time. About 4 hours of lecture. Everything from trail etiquette to how lockers work to HAM radios to parts to bring. 2 hours of hands on in 3 areas. Hi lift jack/ packing your rig/ and winching. Then 2 hours of behind the wheel. Practicing spotting, hand signals, and picking lines. We even do a gig on how to safely back down a steep hill.
Mid April. Carniege OHV California
[QUOTE="Michael, post: 55136, member: 1"]If you happen to be in CA we are planning an OHV park get together in 2017 to go through some basic training! Thanks for reading![/QUOTE]
Any ideas on when this might go down? Perhaps I haven't searched the calendar long enough? 😛
Good write up [USER=1]@Michael[/USER]
I look at lockers (and nearly every other modification) like a form of insurance. By that I mean, whether it's lockers, a snorkel, winch, recovery boards, snap straps etc. what's cheaper?
What'a cheaper? A locker or a tow bill to get out of a whole you stuck in?
What's cheaper? A snorkle or a new engine?
Some people see these modifications and laugh. "Why do you have it if you haven't used it!?" Because if I need it, I'll be happy I have it. And again…it's cheaper then the alternative.
Lockers saved the day last month on a trip gumbo mud and no winch their was pucker factor but I kept going till I got out still debating that winch 🙂
but a snorkel on a gas rig? maybe for the dust that is if your not first on race day.. a diesel I can see if your crossing deep water but anyone I seen try that here got washed downstream some vehicles never to be seen again well that was until a buddy of mine took a rafting trip down a river and ended up very worried about the amount of gnarly sharp vehicle metal that could have ripped the raft and him as well so very common thing for vehicles to get washed down rivers…
When I was looking at the big picture about what I needed for my Overland Rig,. I was looking at failure points and talking to my Jeeping brothers and sisters, one thing kept popping up their lockers had issues at one time or another be it wires or air hoses or they just jammed up. To me the locker option was a No Go [emoji107] The direction I went with was the Detroit TrueTrac, always working and they have not let me down yet on any of my excursions.
And to add they half the price of traditional lockers.
[QUOTE="Gnasher_PNW, post: 55618, member: 3244"]Any ideas on when this might go down? Perhaps I haven't searched the calendar long enough? :P[/QUOTE]
The date isn't set yet but it would be great to see you!
[QUOTE="mitchandbuck, post: 55611, member: 5139"]My jeep club has been doing this for a few years too. Safety clinic, hands on and practice time. About 4 hours of lecture. Everything from trail etiquette to how lockers work to HAM radios to parts to bring. 2 hours of hands on in 3 areas. Hi lift jack/ packing your rig/ and winching. Then 2 hours of behind the wheel. Practicing spotting, hand signals, and picking lines. We even do a gig on how to safely back down a steep hill.
Mid April. Carniege OHV California[/QUOTE]
Is this Esprit De Four you're talking about? I've heard good things about their Safety Clinics.
Nice article [USER=1]@Michael[/USER]! I'd agree that lockers aren't needed for overlanding. There are lots of places to explore where they aren't needed. Sometimes I think all they do is get you more stuck! Don't forget, if you want lockers that means you'll need stronger axles (and cv's if you're doing the front). That means you can get turn bigger tires, so you'll need a bigger lift 😉
Lockers are a gateway mod…
You won't need them till you need them.
[QUOTE="Disco2Guy, post: 56382, member: 1294"]Is this Esprit De Four you're talking about? I've heard good things about their Safety Clinics.[/QUOTE]
We are Diablo 4 wheelers.
Esprit Del four is also a great club that puts their safety clinic on at Hollister Hills
Can't make it through the day? Back up, and get a run at it!
[QUOTE="SilverSurferJKU, post: 56354, member: 3470"]When I was looking at the big picture about what I needed for my Overland Rig,. I was looking at failure points and talking to my Jeeping brothers and sisters, one thing kept popping up their lockers had issues at one time or another be it wires or air hoses or they just jammed up. To me the locker option was a No Go [emoji107] The direction I went with was the Detroit TrueTrac, always working and they have not let me down yet on any of my excursions.
And to add they half the price of traditional lockers.[/QUOTE]
Just keep in mind that a limited slip or non selectable locker is not always the best choice for all persons in all climates. Here in MN with the potential for sketchy / icy roads from November through April, sometimes having the ability to leave the axle(s) open/unlocked is better safer. If you have ever had the tail of your truck wag on you in the middle of winter on the highway, you know what I mean….
My FJ62 had powertrax auto locker installed in the rear diff when I bought it and I have wondered about how it compares to the selectable types. Not sure it has ever engaged since I’ve owned it… also, not sure I would be able to tell. I’m also a novice driver though, so I need to find a clinic like you guys are talking about near Atlanta, GA…
Not real close to Atlanta but you might try this http://www.overlandexperts.com/industrial/locations/north_carolina.php
I have a Lokka locker in my front D30 axel. I did install chrome moly axles with super joints to toughen it up some. I also have limited slip in my rear diff and surprisingly it's worked very well. I recently was in some mud that was over my rock sliders and my only way out was filled with knarly tree roots in the mud. It took a few attempts but I did manage to crawl out over the roots. I wouldn't have been able to do that without it being locked.
Yea I wouldn't say you would need them, you just need to know what the limits of your vehicle are. So don't go rolling into terrain you can't get out or get your vehicle damaged.
To answer the original question,"do you need lockers for overlanding?" I'd have to say that for us, yes. But that is just us. We go alone, way more often than not. Being alone requires finesse driving techniques be utilized and lockers allow me to finesse my way over, sometimes, extremely rough terrain. With open differentials you end up powering through a lot of terrain which leads to premature breakage of driveline components let alone just beating you and your rig up. Powering through also leads to even more degradation of the unmaintained high clearance 4×4 road. I simply cannot recall the last time I have broken traction except in muddy conditions, and even then the loss of traction was minimal. Automatic lockers, ( ie Detroit lockers or any other brand) are all fine and well until you end up in the ditch after sliding around on a wet or snow covered paved road. Interesting side note: a high clearance two wheel drive vehicle with a rear locker can traverse a lot more trails than a high clearance 4 wheel drive vehicle without lockers. Ask me how I know? My first overlanding rig was one of these..
[ATTACH=full]56023[/ATTACH]
I address lockers as safety and insurance when going off-road.
same as off-road worthy tires.
You can overland in an AWD or a 2WD vehicle, and have the time of your life, but your limited by where you can go.
if you overland with a real off-road vehicle, you might as well use it’s added value, and have lockers.
Especially if you travel solo.
It enable you to drive slower, in more controlled manner, with less risk for breakage.
From my personal experience, digging or winching, is not always possible, and often the result of getting stuck where lockers would traverse you safely.
So yes,
If you overland goals go beyond the beaten track, you want lockers.
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[QUOTE="Michael, post: 54982, member: 1"]Michael submitted a new blog post on the main site!
Do You NEED Lockers for Overlanding?
https://www.overlandbound.com/wp-content/upload…
[URL='https://www.overlandbound.com/need-lockers-overlanding/'%5DContinue reading the Original Blog Post.[/URL][/QUOTE]
No, off road it’s nice to have but an LSD or a good traction control can do 99.9% of anything. Look at those new landrovers what with 22 inch wheels climbing all over Moab with a set of Pirelli p zeros and a Starbucks precariously balanced on the laps of the kids on there way to school. Just a point worth making
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[QUOTE="TurboDiesel67, post: 220759, member: 14792"]No, off road it’s nice to have but an LSD or a good traction control can do 99.9% of anything. Look at those new landrovers what with 22 inch wheels climbing all over Moab with a set of Pirelli p zeros and a Starbucks precariously balanced on the laps of the kids on there way to school. Just a point worth making
Sent from my preposterously confusing iPad using OB Talk[/QUOTE]
I'e been wheeelin in the Moab region quite often. Most of the time one is either on slickrock, or going to be on slickrock. Lockers engaged on slickrock =s breakage. Instead of traction control I've become quite nimble at turning the locker switch on and off as necessary. LSDs are ok when they are new, but they wear out very quickly. When a traction control module fails, I don't even wanna think of the consequences nor the expense. But hey, I'm old school, give me old fashioned reliability of an on/off switch. cheers!
The only other thing I would add is… if you have an e-locker USE IT….
If you have an e-locker and never use it… it may not lock in when you need it. They have a tendency to gum up and/or take forever to engage if you never or hardly ever use it.
[QUOTE="TurboDiesel67, post: 220759, member: 14792"]. Look at those new landrovers what with 22 inch wheels[/QUOTE]
Off-road vehicle equipped with lockers and TC, as those LR, and wearing 22” rim and low profile tires, is a heavy weight boxer wearing stilettos..
They blew tire just by touching the sidewalk.
I would say yes. We usually travel as a single vehicle and have used the rear locker many times to navigate deep sand, mud and to getting unstuck quickly… That and some maxtraxxs and a shovel and it gets us out almost every time 🙂
Thanks for the post! It definitely was something I was wondering about with my Tacoma TRD Sport. So far been able handle everything we’ve done but will be an addition down the the road.
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