Selectable diff locker debate (aftermarket).

baldilocks

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I went down to Johnson Valley recently to go wheeling with @Broski and @mustcamp on the first day I ripped teeth from my front ring and pinion and simulateously broke the CV head of the driveline right at the transfer case output.

My ARB air lockers have worked flawlessly since the diffs were built 12 years ago. I have been told by a couple shops that they don’t like to install air lockers anymore due to “too many issues” mostly air leaks and that they steer customers toward the Harrop Eaton E-locker and that if I keep the ARB’s I should replace all seals including the bonded seal on the inside of the carrier. After some research I learned that there are some ARB’s out there from the 1980’s that have never had the bonded seal replaced. ARB claims that the bonded seal can do up to 20k cycles. I like the air lockers and couldn’t really find any negative comments from internet posts years in the past until present. It seems odd that those two shops, one a cruiser shop and one a diff only shop, said that they don’t like the Air Lockers.

I thought, well, this might be a good time to swap to the Eaton when I tear it apart to fix the broken gears myself. So I watched a very good video that compares and shows how the ARB, the Eaton and the TJM pro lockers all operate. I am not impressed with how the Eaton locks and then unlocks for about .5 of a tire rotation when switching directions forward to reverse and back.

If you have experience with any of these selectable lockers post what you know.
 
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I went down to Johnson Valley recently to go wheeling with some other guys and on the first day I ripped teeth from my front ring and pinion and simulateously broke the CV head of the driveline right at the transfer case output.

My ARB air lockers have worked flawlessly since the diffs were built 12 years ago. I have been told by a couple shops that they don’t like to install air lockers anymore due to “too many issues” mostly air leaks and that they steer customers toward the Harrop Eaton E-locker and that if I keep the ARB’s I should replace all seals including the bonded seal on the inside of the carrier. After some research I learned that there are some ARB’s out there from the 1980’s that have never been had the bonded seal replaced. ARB claims that seal can do up to 20k cycles. I like the air lockers and couldn’t really find any negative comments from internet posts years in the past until present. It seems odd that those two shops, one a cruiser shop and one a diff only shop, said that they don’t like the Air Lockers.

I thought, well, this might be a good time to swap to the Eaton when I tear it apart to fix the broken gears myself. So I watched a very good video that compares and shows how the ARB, the Eaton and the TJM pro lockers all operate. I am not impressed with how the Eaton locks and then unlocks for about .5 of a tire rotation when switching directions forward to reverse and back.

If you have experience with any of these selectable lockers post what you know.
I have been considering the Eaton lockers, but after you posted the info about them unlocking for that change in rotation from fwd to rev, then that is an absolute no-go for me. I have blown up differentials doing exactly that and that is why I would own a Detroit locker. However, if Eaton truly works that way, then no.

I want to find out more about that.
 

Broski

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I have been saying it for years ARBs have the fair share of issues!
Some other Guy
 

baldilocks

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I am interested in what experienced Eaton owners know. I read posts on other forums where guys took the tacitly installed Eaton out and installed an ARB because they couldn’t stand the lock/unlock/lock action if the Eaton.
 
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Personally, I miss the ARBs I had in my white 91. The most common problem was overpressuriation of the units. The pressure switch that they used to sell with the compressor kit was set too high and had too wide a window of operation. They recommend 90 psi, but I regulated that down to 68-70. Always locked reliably, never a problem since.
Many folks like the Eaton/Harrop, but I already have an OBA system, so air lockers would be my first choice.
I did have some weld splatter that melted the rear air line, but a quick coupler fixed that right up in about 5 minutes.
 

Broski

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Just put your ARB back in there. Or did you brake that to ?
 

baldilocks

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Just put your ARB back in there. Or did you brake that to ?
I haven’t torn it apart yet but at camp, with it in Jack stands the locker seemed to be working. I was told by a good source that my ARB’s are from an era where they were less trouble. Apparently ARB changed a few things which is why he didn’t like them anymore.
 
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I had lockers and a regear done earlier this year at Slee. I wanted to go with the harrop / eatons but they convinced me to go with the ARB. I was told they no longer install the e lockers as they have had issues with warranty claims.

They were very helpful answering all my questions.
 

baldilocks

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Personally, I miss the ARBs I had in my white 91. The most common problem was overpressuriation of the units. The pressure switch that they used to sell with the compressor kit was set too high and had too wide a window of operation. They recommend 90 psi, but I regulated that down to 68-70. Always locked reliably, never a problem since.
Many folks like the Eaton/Harrop, but I already have an OBA system, so air lockers would be my first choice.
I did have some weld splatter that melted the rear air line, but a quick coupler fixed that right up in about 5 minutes.
This is good info. Mine are from 2010. In 2014 or 2015 my compressor started cycling every 10 seconds while the lockers were engaged. After receiving no relief by replacing both seal housing, both bulkhead fitting O-rings and verifying the integrity of all connections I tracked it down to there being no O-rings sealing the compressor tank. I referred to the compressor explode diagram and saw there were supposed to be O-rings. How did it not leak until 4-5 years post install? I went to Home Depot and found O-rings that fit. This many years later and not one hiccup.

When I went to the tapered coils and 6” lift shocks in 2017 I did manage to rip the front air line because of the increase down travel but that was my fault.
 

baldilocks

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I had lockers and a regear done earlier this year at Slee. I wanted to go with the harrop / eatons but they convinced me to go with the ARB. I was told they no longer install the e lockers as they have had issues with warranty claims.

They were very helpful answering all my questions.
Two well known shops told me ARB’s suck and Slee steers you toward the ARB.

This post is a big part of the reason I started this thread. Good stuff right there.
 
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So two well known shop tells me ARB’s suck and Slee steers youbtiward the ARB.

This post is a big part of the reason I started this thread. Good stuff right there.

Early Harrop's had some issues related to the welded tabs on the magnet. The welds would eventually fail causing the magnet to spin and basically pull in your wiring harness and bind it up inside. MY understand is Harrop has fixed this but I dont know for a fact. I suspect a lot vendors bailed just on that reputation alone. MadMatt 4WD has a good video on the youtube about his Harrop.

That said, I've seen an ARB carrier completely fail on Fordyce in a 2nd gen Taco so they aren't as bulletproof as many say.

As far as the locker debate. I don't like added complexity of air lines and manifolds nor a dependency on air as you can usually jump an e-locker if needed so I tend to always lean toward e-lockers and auto-lockers. Harrops do unlock on roll back but I havent seen complaints from people who actually use one, just the theorists who dont like the "idea" of it. That being said, I am really liking the TJM design for an air locker however they do not have a large presence in the US.
 
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So two well known shops tells me ARB’s suck and Slee steers you toward the ARB.

This post is a big part of the reason I started this thread. Good stuff right there.

I think lots of installers have their opinions influenced by their relationship with the manufacturer. I did lots of reading on MUD and was leaning toward the e lockers until I spoke with them. They used to install the Harrop / Eaton lockers (I think they are the same? Isn't a Harrop just a modified Eaton?). When they had issues with some failing the manufacturer would pay for the parts, but not for the labor. On the other hand they told me in the few instances where they have seen an ARB locker fail ARB has paid for the parts and their labor for the replacement. That was the final deciding factor for me. If I was doing the installation myself it would have been a moot point but when planning to write a check that size I felt better knowing if I had any issues both the manufacturer and installer were going to be there to stand by their work.
 

mudgudgeon

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I went down to Johnson Valley recently to go wheeling with some other guys and on the first day I ripped teeth from my front ring and pinion and simulateously broke the CV head of the driveline right at the transfer case output.

My ARB air lockers have worked flawlessly since the diffs were built 12 years ago. I have been told by a couple shops that they don’t like to install air lockers anymore due to “too many issues” mostly air leaks and that they steer customers toward the Harrop Eaton E-locker and that if I keep the ARB’s I should replace all seals including the bonded seal on the inside of the carrier. After some research I learned that there are some ARB’s out there from the 1980’s that have never been had the bonded seal replaced. ARB claims that seal can do up to 20k cycles. I like the air lockers and couldn’t really find any negative comments from internet posts years in the past until present. It seems odd that those two shops, one a cruiser shop and one a diff only shop, said that they don’t like the Air Lockers.

I thought, well, this might be a good time to swap to the Eaton when I tear it apart to fix the broken gears myself. So I watched a very good video that compares and shows how the ARB, the Eaton and the TJM pro lockers all operate. I am not impressed with how the Eaton locks and then unlocks for about .5 of a tire rotation when switching directions forward to reverse and back.

If you have experience with any of these selectable lockers post what you know.

Link to the video?

There's a long history of failed seals in ARB lockers, it was talked about a lot maybe 10 years ago.
I think at one point ARB changed seal materials and had issues.
That and, if installers weren't careful, seals were being damaged on install.
Another common failures was the copper line inside the housing getting nicked by the crown wheel due to install issues.
I've seen ARB Airlockers referred to as ARB Airleakers many times.

I looked at ARB vs TJM years ago. At the time, the availability of TJM was limited, so there wasn't a lot of feedback from experienced installers.

I'd go for ARB for aftermarket lockers. They are well proven and well understood. I think the issues are a fairly small percentage of a huge volume of product sold and used across any popular 4x4 platform you can think of
 

baldilocks

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If the Harrops disengage on roll back, does that mean they don't function in reverse?
Harrop’s use a roller cam and three ball bearings. When the magnet is energized, and then you roll, the roller cam (actually a flat plate/ring that is machined with grooves that those ball bearings ride in is forced out word as the balls roll up into higher land. This takes about 1/4 axle shaft rotation. You are now locked. Reverse and the ring rotates back 1/4 turn, this is now unlocked. Another 1/4 turn in reverse and the locker locks up again.

How can this be good for axle shafts and diff’s? If a user is traversing very mild terrain all the time this may not be detrimental but rock crawling in serious stuff sometimes requires getting into wheel spin to heat those tires up. I can’t see being in a bind and liking how I loose lock up for .5 rotation of my tires.

The Eaton costs $1313 for an 80 series front differential.

No video or photos were taken. It was all guys and no passengers plus were only minutes out of camp.
 
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My ARB's had to be removed and re-sealed or I could have ignored the gear oil spewing out of the compressor along with the smell and just kept topping off the diffs.
 
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All of these noted issues are why I put detroits in mine, front and back
and once you get used to them they are very predictable in their driveability and you can always depend on them to work
the issues of it being hard to steer is kind of a non issue as you can shift out of 4x if you need to
i realize this thread isnt about the viability of non selectable vs selectable lockers... but you can mitigate alot of said issues by going detroits
and in my mind its actually easier on things as you dont have the front diff trying to change the tires thats spinning when in 'open diff mode'
just a thought
 

baldilocks

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All of these noted issues are why I put detroits in mine, front and back
and once you get used to them they are very predictable in their driveability and you can always depend on them to work
the issues of it being hard to steer is kind of a non issue as you can shift out of 4x if you need to
i realize this thread isnt about the viability of non selectable vs selectable lockers... but you can mitigate alot of said issues by going detroits
and in my mind its actually easier on things as you dont have the front diff trying to change the tires thats spinning when in 'open diff mode'
just a thought
Thank ls for your input. Detroit’s I’ve had. They are great in a vehicle that’s mostly off road. An auto locker brings up the pucker factors on hard packed snow and ice.
 

Haggis

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I discussed this with a nice gentleman at Georg's shop Valley Hybrids in Stockton. My 80 didn't come with the lockers and I'd like to add them. He seemed to think Harrop is the way to go and what I probably will do in the very near future.
 

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