For those who wheel harder than I do: What are the downfalls of MTS/ATRAC? Do I really need an e/air locker?

[CanadianRockyCruiser]

I've been debating lockers for a long time. Once upon a time I had a rear locker in a 4runner and another in my ol' LX470. I've had lots of fun offroading with ATRAC in my 2013 LX570, and I am debating the value of adding e/air lockers.

I'm looking for advice as to the downfalls of MTS/ATRAC compared to diff lockers. When you are wheeling harder than I probably ever will, what are the tactical advantages of e/air lockers compared to MTS/ATRAC?

Thanks in advance for the insights. I'm basically debating adding rear, and perhaps later a front locker, but questioning if I really will get use and value from them, as I'll soon dedicate my LX to 4x4 fun and adventures rather than daily-driver (less city use).

 

[riffman12]

I've had an e-locker in a 4runner then ATRAC in all my Land Cruisers.

The best way I can describe it is that with a locker, there is no time for the vehicle to "think" or "figure out" which wheel to send power to. It's instant. That next quarter of a wheel rotation has both wheels putting down equal power.

With the electronic systems it often takes a bit of wheel turning for the system to know what to do.

In most cases both systems will get you up the same obstacle, but if you're right at the crest of a rock and NEED the vehicle to start moving forward with zero rollback, a locker will always be more effective.

Rear locker makes the most difference in my experience. Front if you really need to get into some hairy stuff.

 

[Heckraiser]

I'm a locker guy mainly because I began wheeling before all the electronic alternatives came around. I'm a "hold my beer" wheeler and usually pick the harder lines, not too scared of beating up the truck--that's what I bought it for. I'm not a big fan of ATRAC, just feel like more slippage than the positive engagement of a locker and when you're really trying to climb over that bump, ATRAC just doesn't cut it sometimes. To me, ATRAC feels more like the old-school trick of gas and brake at the same time, but on steroids. I'm also spoiled by a long line of locked rigs (many of them front and rear locked). I spent the $$$ for front and rear Eatons in my minivan and don't regret it one bit. FWIW, I have run ARB lockers, e-lockers (OEM and aftermarket) and lunchbox lockers. I prefer e-lockers over air lockers for reliability/simplicity. Lunchbox for parking lot donuts

All that said, my recommendation to you if you're making your LX into more of a wheeling rig is just go out there and put it through it's paces. If you find yourself running into the limitations of ATRAC, then spring for the lockers. No need to decide now. It will depend a lot on where you wheel as well.

 

[coleAK]

I had triple lockers on my 80 and g500 I had prior to my LX570 and my daughters ZR2 is triple locked. I wheel pretty hard with the LX and have personally never felt the need for adding them. In the rare event I need ATRAC I kick it on for a few min got through the situation, move on. Another point to make for ATTAC I think it is better in soft sand than lockers. Many times in my experience lockers do more harm (dig holes) than good in the soft stuff.

My advice is the same as others. Don’t add them until you see a real need and if so rear is likely all you would need.

 

[kcjaz]

The best way I can describe it is that with a locker, there is no time for the vehicle to "think" or "figure out" which wheel to send power to. It's instant. That next quarter of a wheel rotation has both wheels putting down equal power.

With the electronic systems it often takes a bit of wheel turning for the system to know what to do.

Well said. MTS/ATRAC are great and generally will do all that most people. Whether or not you “need” lockers depends on what you plant to be doing with your rig, how heavy your build gets, and what other recovery equipment you have. For example, I’d add a winch before adding lockers. Another thing is do you adventure solo and need to be able to get yourself out of situations or have the best chance of avoiding them all together. Here is a video of me before lockers. On the 3rd and final attempt, you can see MTS stop the passenger rear tire which put traction to the driver side and up the climb I went. With a rear locker I likely would have made it on the first shot.



The only “downside” I’ve noticed w/ MTS is that sometimes the MTS will kick in and kill forward momentum as it’s really trying to crawl you over the obstacle. You can manage this with the terrain select dial. I think of it as a “variable slip” locker. I usually keep terrain select in “sand” mode to provide the most slip and just drive. If I’m really going to rock crawl up something I may dial up to “rock” mode. If I can’t make it up and over, I go rear locker. If that doesn’t work, I go triple lock. Triple locked is like hitting a cheat button. The first time I did “The Wall” I got stuck half way up with only rear locker on. I debated whether to hit the front locker or back down. I decided to go front locker and just walked up. The down side to front locker is that you can’t effectively steer and if you lift a corner, and your free spinning tire suddenly gets traction, you can break a CV.

 

[CanadianRockyCruiser]

I've had an e-locker in a 4runner then ATRAC in all my Land Cruisers.

The best way I can describe it is that with a locker, there is no time for the vehicle to "think" or "figure out" which wheel to send power to. It's instant. That next quarter of a wheel rotation has both wheels putting down equal power.

With the electronic systems it often takes a bit of wheel turning for the system to know what to do.

In most cases both systems will get you up the same obstacle, but if you're right at the crest of a rock and NEED the vehicle to start moving forward with zero rollback, a locker will always be more effective.

Rear locker makes the most difference in my experience. Front if you really need to get into some hairy stuff.

Perhaps I'll just have to wheel harder and get as stuck as I can before buying and installing lockers. Push the limits a bit more, so to speak. I've only been truly stuck once at Suffield Forces Base in mud that wouldn't negotiate with CRAWL and nothing to winch off of nearby (a ground anchor would have been ideal).

I can see the value of locking in advance of obstacles, as opposed to responding after a wheel is spinning. Guess I'll just have to attempt more aggressive lines to test my needs more.

The nice thing is I have my stock diffs on a shelf (swapped 4.3's as fully built toyota diffs), so I can install lockers/gears at home, and take my time without putting the vehicle out of service.

 

[hoser]

I prefer lockers over ATRAC/MTS for a recreational wheeling. ATRAC for an overland vehicle. Having both is the best of all worlds but I'd like to be able to turn the traction aids off. The fun is trying to get through an obstacle..... not bragging to your buddy how easy it was for you. But the worst is having to take a strap/winch help. In which case, I will take all the traction aids I can get before asking for a strap!

 

[TeCKis300]

I find lockers to be key in surfaces that are low traction and dynamic - meaning terrain that easily moves around as power is being put down. Like sand, small rocks that work like marbles, loose dirt, etc.. Brake based and even torque biasing (like EVs) traction devices are reactive to wheel spin so they only come into play once the terrain has already disturbed and wheels are spinning. Usually due to too much torque being applied at that wheel. Lockers make tires work in unison so torque and power is more evenly put down across drive wheels, minimizing wheel slip and digging/disturbing into terrain. Often once the terrain is disturbed, less traction is available at that slipping wheel.

This video shows it well. It's steeper and the moguls larger than it appears. The front axle is largely unloaded due to the incline. Center locker is already on at the start, also turning off traction control to allow wheelspeed.

You can see ATRAC trying to do its thing with limited effect. At which point I lean over to put in the rear locker at around 20 seconds into the video. Progress is tremendously more sure footed after that.

 

[RET2]

I find lockers to be key in surfaces that are low traction and dynamic - meaning terrain that easily moves around as power is being put down. Like sand, small rocks that work like marbles, loose dirt, etc.. Brake based and even torque biasing (like EVs) traction devices are reactive to wheel spin so they only come into play once the terrain has already disturbed and wheels are spinning. Usually due to too much torque being applied at that wheel. Lockers make tires work in unison so torque and power is more evenly put down across drive wheels, minimizing wheel slip and digging/disturbing into terrain. Often once the terrain is disturbed, less traction is available at that slipping wheel.

This video shows it well. It's steeper and the moguls larger than it appears. The front axle is largely unloaded due to the incline. Center locker is already on at the start, also turning off traction control to allow wheelspeed.

You can see ATRAC trying to do its thing with limited effect. At which point I lean over to put in the rear locker at around 20 seconds into the video. Progress is tremendously more sure footed after that.

Going up the down?

 

[RET2]

Going up the down?

 

[TeCKis300]

Going up the down?

I hear ya and I'm respectful of these things. We asked some rangers 3 years back and they said it's no longer enforced.

 

[RET2]

I hear ya and I'm respectful of these things. We asked some rangers 3 years back and they said it's no longer enforced.

I must agree it makes things more interesting. FWIW I enjoyed the info seeing as we have similar rides.

 

[bicycleagent003]

I find lockers to be key in surfaces that are low traction and dynamic - meaning terrain that easily moves around as power is being put down. Like sand, small rocks that work like marbles, loose dirt, etc.. Brake based and even torque biasing (like EVs) traction devices are reactive to wheel spin so they only come into play once the terrain has already disturbed and wheels are spinning. Usually due to too much torque being applied at that wheel. Lockers make tires work in unison so torque and power is more evenly put down across drive wheels, minimizing wheel slip and digging/disturbing into terrain. Often once the terrain is disturbed, less traction is available at that slipping wheel.

This video shows it well. It's steeper and the moguls larger than it appears. The front axle is largely unloaded due to the incline. Center locker is already on at the start, also turning off traction control to allow wheelspeed.

You can see ATRAC trying to do its thing with limited effect. At which point I lean over to put in the rear locker at around 20 seconds into the video. Progress is tremendously more sure footed after that.

Where is that location? And what's the reference to up the down? Thanks.

 

[TeCKis300]

Where is that location? And what's the reference to up the down? Thanks.

This is Diablo Drop-off in Anza Borrego State Park. Historically a one way route to get from the higher rim down to Fish Creek wash.

It's become a test and tune playground of sorts that now has 5-6 routes with varying technical challenges. You'll find groups there on the regular spectating and playing. Rivian themselves were out there years ago with a pre-release video demonstrating R1T chops going up the down. Which is what prompted us to reach out to rangers to get clarify.

Over the years, the terrain has changed significantly between the state plowing routes flat, erosion, and use. AWDs will generally not get up without traction aids or locking devices. Moguls inevitably get dug out from those vehicles without lockers trying. And they get bigger than ever as factory and enthusiast tire fitments get larger. Almost like a cold arms race where 35s are the new 33s.

 

[bicycleagent003]

This is Diablo Drop-off in Anza Borrego State Park. Historically a one way route to get from the higher rim down to Fish Creek wash.

It's become a test and tune playground of sorts that now has 5-6 routes with varying technical challenges. You'll find groups there on the regular spectating and playing. Rivian themselves were out there years ago with a pre-release video demonstrating R1T chops going up the down. Which is what prompted us to reach out to rangers to get clarify.

Over the years, the terrain has changed significantly between the state plowing routes flat, erosion, and use. AWDs will generally not get up without traction aids or locking devices. Moguls inevitably get dug out from those vehicles without lockers trying. And they get bigger than ever as factory and enthusiast tire fitments get larger. Almost like a cold arms race where 35s are the new 33s.

View attachment 4031657

Okay cool. Thanks for the info. I've been in that area but not to that obstacle. I'll check out it. I'll find out if my 33's and lockers can hang. Thanks again.

 

[TimCFJ40]

Have had both in several Toyota and non Toyota 4x4s over the years.
The reality is that for 99.9% of people ATRAC/Crawl/MTS will do anything and more that they should be doing in a 200 series. I've made it up ledges with ATRAC (not even CRAWL) that my brother in law's Rubicon needed the lockers for.

That said:
Locker Pros:
Quiet - Crawl makes all sorts of sounds doing what it does. I've been lambasted here before for saying it, but if you've had a 3x locked truck, you'll understand. There's nothing but engine and tire noise.
Predictable - Once the lockers are engaged, you get power 100% to all 4 tires. There's no waiting or guessing when it'll kick in and do it's thing. For precise rock crawling, sometimes it's a guess when CRAWL is going to find the right magic to move forward.
Capable - There is a limited set of circumstances where only full lockers are going to get you there

Locker Cons:
Cost - no way around it, you're in $3-5+k depending on what you get and who installs them.
Harder on parts - Depending on how you drive, you definitely have a higher likelihood of breaking stuff. ATRAC/CRAWL might back down when your lockers will let you break stuff

ATRAC/Crawl Pros:
Free - You already paid for it
Invisible for daily driving - No additional parts/maintenance
Easier on parts - Toyota designed with the driveline in mind, MIGHT protect you from your stupidity.

ATRAC/Crawl Cons:
Noisy in action - Again bring the haters...
Perhaps limited capability at the very extreme end
Less precise control by driver

If I somehow got a set of Lockers installed for free, I'd certainly take them, but the onboard CRAWL/ATRAC suite of magic does 99% of what I need with no real downside.

 

[coleAK]

Have had both in several Toyota and non Toyota 4x4s over the years.
The reality is that for 99.9% of people ATRAC/Crawl/MTS will do anything and more that they should be doing in a 200 series. I've made it up ledges with ATRAC (not even CRAWL) that my brother in law's Rubicon needed the lockers for.

That said:
Locker Pros:
Quiet - Crawl makes all sorts of sounds doing what it does. I've been lambasted here before for saying it, but if you've had a 3x locked truck, you'll understand. There's nothing but engine and tire noise.
Predictable - Once the lockers are engaged, you get power 100% to all 4 tires. There's no waiting or guessing when it'll kick in and do it's thing. For precise rock crawling, sometimes it's a guess when CRAWL is going to find the right magic to move forward.
Capable - There is a limited set of circumstances where only full lockers are going to get you there

Locker Cons:
Cost - no way around it, you're in $3-5+k depending on what you get and who installs them.
Harder on parts - Depending on how you drive, you definitely have a higher likelihood of breaking stuff. ATRAC/CRAWL will might back down when your lockers will let you break stuff

ATRAC/Crawl Pros:
Free - You already paid for it
Invisible for daily driving - No additional parts/maintenance
Easier on parts - Toyota designed with the driveline in mind, MIGHT protect you from your stupidity.

ATRAC/Crawl Cons:
Noisy in action - Again bring the haters...
Perhaps limited capability at the very extreme end
Less precise control by driver

If I somehow got a set of Lockers installed for free, I'd certainly take them, but the onboard CRAWL/ATRAC suite of magic does 99% of what I need with no real downside.

Well said. I used the rear locker often (and rarely front) in the g500 I had for 9 years prior (and the triple locked 80 before the g) to my ‘13 LX that I’ve now had for 12 years. I use the lockers in my daughter’s Colorado ZR2. But I’ve never felt the need for a rear locker in my LX enough to pay for it.

 

[TeCKis300]

This is going depend on how hard one wheels. You'll know when you're at the limits of what ATRAC and CRAWL will do. There's obstacles beyond those capabilities where a rear locker makes the difference. Even with 37s and rear lockers, there's been obstacles I've been denied on where a front locker would have made the difference. This is what happens when you have a buddy that has a triple locked Rubicon and enjoys seeking out obstacles.

For overlanding, ATRAC and CRAWL all day.

 

[dms]

Without starting a war over e-locker vs ARB, I will be really interested in seeing which locker you pick. I am on the fence for the rear in my 2004 TACO.

 

[Heckraiser]

Since you've got a taco, I'd hunt for a junkyard axle with the stock e-locker. I've used all varieties of lockers over the years, and electronic lockers are my personal choice (OEM Toyota or Eaton)