Let's talk about the Pro's and Con's of different lockers, and our likes and dislikes of each type of locker.
There are two main ways to categorize lockers:
Selectable lockers are lockers that are manually engaged or disengaged via a switch, button, lever, etc. Once the locker is engaged, it stays engaged until you manually disengage it.
The benefit of selectable lockers is that you get to decide when they are engaged and disengaged. Some of the reasons you would want to manually disengage would be when you are in a tight situation and having the front or rear locked could cause difficult steering or binding. You also don't want to have lockers on when you are diving on the road in wet, snowy or icy conditions, as this could cause loss of traction and potentially loss of control. Having a selectable gives you the benefit of choice.
The disadvantages of selectable lockers is that they typically cost more money, they require external components to engage such as a air compressor, air line and solenoid, electric motor, or cable attached to a lever. There are more potential points of failure due to the complexity.
Auto-Lockers are lockers are lockers that automatically engage using mechanical components that lock up the differential once a tire starts to lose traction. This is different than posi-trac or limited slip, because actually locks the differential rather limit the amount of slip to a varying degree (auto-lockers are either on or off, nothing in between), but works in a similar way.
The benefit of an auto-locker is that they are usually cheap, easy to install, and don't require any extra parts to engage since they engage on their own without the need for manual engagement from the driver.
The disadvantage of auto-lockers is that they will lock when you don't always want them to, they can be noisy when turning due to the clicking nature of some of them, they typically aren't as strong as some of the selectable locker options.
Types of Selectable Lockers
Air Lockers are actuated by using pressurized air to lock the differential. This is done by using an air compressor or an air tank. There is a solenoid that is activated by an electric switch to allow the pressurized air to activate the locker or release the air to deactivate the locker. So whether you have an air compressor or an air tank, you will still need to wire a switch for the solenoid.
The benefit of air lockers is that they are pretty simple and strong designs (Especially ARB, which is probably the strongest option for selectable lockers). They are typically easy to pinpoint the point of failure which is usually an air leak somewhere. If the air leak is in the air line, it can be an easy trail repair using some extra air line and compression fittings. These lockers air extremely quick to engage and disengage which makes them great for tight situations or racing applications. Also having an air supply is something that can be dual purpose to air up tires.
The disadvantage of these lockers is that they require an air compressor that can fail, or an air tank that can run out of air. The bonded seal in the ARB's has been a known point of failure for the past couple years, and requires you to pull the diff to repair. If you cannot get enough air pressure to your locker, you will not be able to manually activate it in any way.
ARB Air Locker
ARB Compressor and Solenoids
E-Lockers. There are two main types that work in different ways.
One is the Toyota OEM E-Locker that come from the Toyota factory. This one uses an electric motor to drive a gear that moves a shift fork to engage the locker. All done by the push of a button.
The benefit of the Toyota E-Locker is that they come stock on many Toyota vehicles. The biggest benefit in my eyes is that they can be manually engaged if there is an issue with the electrical components or motor. You just gotta pull the electric motor and use a pry bar or something similar to engage or disengage the gear/shift fork.
The disadvantage of the Toyota E-locker is that the differential itself is a inherently weaker design than the standard 8" Toyota diff. The electrical components can also be difficult to track down issues. You cannot engage these at any speed. You must be driving under 5 mph when engaging.
Toyota OEM E-Locker
The next one is the Eaton E-Locker and Harrop E-Locker. They both use the same design and are manufactured by Eaton.
The advantage of the Eaton/Harrop E-Locker is the lack of air compressor or air tank to take up room in your vehicle to add additional switches to your dash. This is all electrical driven using electromagnetics to actuate the locker.
The disadvantage is that they are sometimes more expensive than the Air Lockers, they are not quite as strong, and they do not instantly lock up when you push the button or flip the switch. They take about 270* of tire rotation to fully activate, which can be an issue if you are in a tight situation or have an heavy foot. You cannot engage these at any speed.
Eaton/ Harrop E-Locker
Cable Lockers are lockers that are activated using a cable with a lever similar to parking brakes. There is an actuator that attaches to the inside of the diff cover to engage the locker components in the carrier.
The benefits are that it is a simple mechanical design that doesn't need any electrical or air components to engage. If wanted, there is an air actuator upgrade option.
The disadvantage is that the cable may be hard to engage if the cable has a lot of curves in the line connecting the lever to the diff. There is the cable the hangs out the side of the diff cover that can potentially be exposed to damage. You have to install an additional lever that takes up space in the cab. They are limited to only a few models of axles such as Dana's, Ford 8.8/10.25/10.50, Chrsyler 8.25, GM 8.5/10 bolt, AMC 20. No Toyota or Ford 9" options.
OX Locker
Types of Auto-Lockers:
Lunchbox lockers just replace the spider and side gears only. These can be done without removing the carrier or having to adjust the ring gear backlash since everything stays in place.
The benefit is that they are cheap and easy to install with basic mechanical experience. They work great for an auto-locker and will last a long time to mild abuse.
The disadvantage of a lunchbox locker is that they are not as strong since they retain the original differential carrier.
Lunchbox Locker
Full Carrier Replacement Auto-Lockers (Detroit Locker) are very strong and reliable lockers. They cost more money than a lunchbox locker and take a professional to install properly, however they are much stronger.
The advantage of these are the increased carrier strength compared to the lunchbox lockers. With more strength, there will be less deflection at the ring gear, resulting in a stronger, more reliable differential.
The disadvantage is the cost compared to a lunchbox since they are a more expensive upfront cost as well as the cost to pay a professional to set it up properly.
Detroit Locker
There are Spools and Mini-Spools that leave the deferential locked at all times. There is no engagement/disengagement with these. They are permanently locked.
Mini-Spools just replace the spider and side gears, while a full Spool replaces the entire carrier. Typically these options are left for rigs that only see the trail and are not street driven vehicles, although there are plenty of guys that still run them on weekend warrior type rigs that see plenty of street and dirt.
The benefit is that they are extremely cheap and strong.
The disadvantage is that the diff is locked at all times and makes street driving less attractive and wears tires easily. It also doesn't allow you to unlock in tight situations to help with steering/turning.
Spool
I'm sure I've missing things and might have some things wrong somewhere in there, so feel free to give some feedback or corrections.
There are two main ways to categorize lockers:
- Selectable Lockers
- Auto-Lockers
Selectable lockers are lockers that are manually engaged or disengaged via a switch, button, lever, etc. Once the locker is engaged, it stays engaged until you manually disengage it.
The benefit of selectable lockers is that you get to decide when they are engaged and disengaged. Some of the reasons you would want to manually disengage would be when you are in a tight situation and having the front or rear locked could cause difficult steering or binding. You also don't want to have lockers on when you are diving on the road in wet, snowy or icy conditions, as this could cause loss of traction and potentially loss of control. Having a selectable gives you the benefit of choice.
The disadvantages of selectable lockers is that they typically cost more money, they require external components to engage such as a air compressor, air line and solenoid, electric motor, or cable attached to a lever. There are more potential points of failure due to the complexity.
Auto-Lockers are lockers are lockers that automatically engage using mechanical components that lock up the differential once a tire starts to lose traction. This is different than posi-trac or limited slip, because actually locks the differential rather limit the amount of slip to a varying degree (auto-lockers are either on or off, nothing in between), but works in a similar way.
The benefit of an auto-locker is that they are usually cheap, easy to install, and don't require any extra parts to engage since they engage on their own without the need for manual engagement from the driver.
The disadvantage of auto-lockers is that they will lock when you don't always want them to, they can be noisy when turning due to the clicking nature of some of them, they typically aren't as strong as some of the selectable locker options.
Types of Selectable Lockers
- Air Lockers (ARB, Yukon Zip)
- Electric Lockers (Toyota OEM E-Locker, Eaton E-Locker, Harrop)
- Cable Locker (OX Locker)
Air Lockers are actuated by using pressurized air to lock the differential. This is done by using an air compressor or an air tank. There is a solenoid that is activated by an electric switch to allow the pressurized air to activate the locker or release the air to deactivate the locker. So whether you have an air compressor or an air tank, you will still need to wire a switch for the solenoid.
The benefit of air lockers is that they are pretty simple and strong designs (Especially ARB, which is probably the strongest option for selectable lockers). They are typically easy to pinpoint the point of failure which is usually an air leak somewhere. If the air leak is in the air line, it can be an easy trail repair using some extra air line and compression fittings. These lockers air extremely quick to engage and disengage which makes them great for tight situations or racing applications. Also having an air supply is something that can be dual purpose to air up tires.
The disadvantage of these lockers is that they require an air compressor that can fail, or an air tank that can run out of air. The bonded seal in the ARB's has been a known point of failure for the past couple years, and requires you to pull the diff to repair. If you cannot get enough air pressure to your locker, you will not be able to manually activate it in any way.
ARB Air Locker
ARB Compressor and Solenoids
E-Lockers. There are two main types that work in different ways.
One is the Toyota OEM E-Locker that come from the Toyota factory. This one uses an electric motor to drive a gear that moves a shift fork to engage the locker. All done by the push of a button.
The benefit of the Toyota E-Locker is that they come stock on many Toyota vehicles. The biggest benefit in my eyes is that they can be manually engaged if there is an issue with the electrical components or motor. You just gotta pull the electric motor and use a pry bar or something similar to engage or disengage the gear/shift fork.
The disadvantage of the Toyota E-locker is that the differential itself is a inherently weaker design than the standard 8" Toyota diff. The electrical components can also be difficult to track down issues. You cannot engage these at any speed. You must be driving under 5 mph when engaging.
Toyota OEM E-Locker
The next one is the Eaton E-Locker and Harrop E-Locker. They both use the same design and are manufactured by Eaton.
The advantage of the Eaton/Harrop E-Locker is the lack of air compressor or air tank to take up room in your vehicle to add additional switches to your dash. This is all electrical driven using electromagnetics to actuate the locker.
The disadvantage is that they are sometimes more expensive than the Air Lockers, they are not quite as strong, and they do not instantly lock up when you push the button or flip the switch. They take about 270* of tire rotation to fully activate, which can be an issue if you are in a tight situation or have an heavy foot. You cannot engage these at any speed.
Eaton/ Harrop E-Locker
Cable Lockers are lockers that are activated using a cable with a lever similar to parking brakes. There is an actuator that attaches to the inside of the diff cover to engage the locker components in the carrier.
The benefits are that it is a simple mechanical design that doesn't need any electrical or air components to engage. If wanted, there is an air actuator upgrade option.
The disadvantage is that the cable may be hard to engage if the cable has a lot of curves in the line connecting the lever to the diff. There is the cable the hangs out the side of the diff cover that can potentially be exposed to damage. You have to install an additional lever that takes up space in the cab. They are limited to only a few models of axles such as Dana's, Ford 8.8/10.25/10.50, Chrsyler 8.25, GM 8.5/10 bolt, AMC 20. No Toyota or Ford 9" options.
OX Locker
Types of Auto-Lockers:
- Lunchbox Lockers (Spartan, Aussie, Lock-Right)
- Auto-Locker with Full Carrier Replacement (Detroit, Yukon Grizzly)
Lunchbox lockers just replace the spider and side gears only. These can be done without removing the carrier or having to adjust the ring gear backlash since everything stays in place.
The benefit is that they are cheap and easy to install with basic mechanical experience. They work great for an auto-locker and will last a long time to mild abuse.
The disadvantage of a lunchbox locker is that they are not as strong since they retain the original differential carrier.
Lunchbox Locker
Full Carrier Replacement Auto-Lockers (Detroit Locker) are very strong and reliable lockers. They cost more money than a lunchbox locker and take a professional to install properly, however they are much stronger.
The advantage of these are the increased carrier strength compared to the lunchbox lockers. With more strength, there will be less deflection at the ring gear, resulting in a stronger, more reliable differential.
The disadvantage is the cost compared to a lunchbox since they are a more expensive upfront cost as well as the cost to pay a professional to set it up properly.
Detroit Locker
There are Spools and Mini-Spools that leave the deferential locked at all times. There is no engagement/disengagement with these. They are permanently locked.
Mini-Spools just replace the spider and side gears, while a full Spool replaces the entire carrier. Typically these options are left for rigs that only see the trail and are not street driven vehicles, although there are plenty of guys that still run them on weekend warrior type rigs that see plenty of street and dirt.
The benefit is that they are extremely cheap and strong.
The disadvantage is that the diff is locked at all times and makes street driving less attractive and wears tires easily. It also doesn't allow you to unlock in tight situations to help with steering/turning.
Spool
I'm sure I've missing things and might have some things wrong somewhere in there, so feel free to give some feedback or corrections.
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