FAQ Axle - Gears - Lockers GX470 Upgrade Thread (4 Viewers)

[Rednexus]

Stories like this are what concern me regarding an ARB:

Brand new ARB locker leaking air

Well.....I’m not sure where to point blame, but I’m not too happy about this. I ordered a rear diff and ARB locker complete through ECGS in January and...

www.tacomaworld.com

A Harrop seems like a more reliable design, using electricity instead of compressed air with seals, o-rings, and multiple failure points. When I do this upgrade, it will probably be something that I go months without using at a time, rather than something that gets used weekly for rockcrawling. Under that kind of use, it seems that a electrical-based system would be much more reliable than air.

 

[jiggletits]

Stories like this are what concern me regarding an ARB:

Brand new ARB locker leaking air

Well.....I’m not sure where to point blame, but I’m not too happy about this. I ordered a rear diff and ARB locker complete through ECGS in January and...

www.tacomaworld.com

A Harrop seems like a more reliable design, using electricity instead of compressed air with seals, o-rings, and multiple failure points. When I do this upgrade, it will probably be something that I go months without using at a time, rather than something that gets used weekly for rockcrawling. Under that kind of use, it seems that a electrical-based system would be much more reliable than air.

Exactly

 

[captainva]

Is the Eaton e-locker work differently than the Harrop? Ahhh...never mind. Seems like Eaton is Harrop.

There are reports that the Harrop e-locker was designed to disengage if you roll backwards (change directions). That’s something to think about when choosing a locker.

And I was in the 200-section where this was discussed. It only impacts you if you are in terrain that might force you to roll backwards or you need to reverse to align your line. Anyone running a Harrop rear e-locker? - https://forum.ih8mud.com/threads/anyone-running-a-harrop-rear-e-locker.1036418/post-11432149

This is true. It will disengage if you roll back and re-engage in about a half turn of the wheels. This really isn't an issue and a friend that has one has been very happy with his.

 

[Jstawgn]

Stories like this are what concern me regarding an ARB:

Brand new ARB locker leaking air

Well.....I’m not sure where to point blame, but I’m not too happy about this. I ordered a rear diff and ARB locker complete through ECGS in January and...

www.tacomaworld.com

A Harrop seems like a more reliable design, using electricity instead of compressed air with seals, o-rings, and multiple failure points. When I do this upgrade, it will probably be something that I go months without using at a time, rather than something that gets used weekly for rockcrawling. Under that kind of use, it seems that a electrical-based system would be much more reliable than air.

ARB fixed this problem years ago. This was a bad batch of seals. More common is the copper line got damaged during install.

ARB is the fastest to engage and disengage. The only one that will work when combined with cutting brakes for competition.

Easton elocker are definitely easier to install. OEM 8.75 tacoma elocker are based on similar design. Similar with jeep locker but they are really problematic with they way they wore and integrate with ECU.

 

[captainva]

Yup ARB will lock basically instantly without requiring the wheels to roll and stay locked until you flip the switch back to unlocked. Only downside is potential rebuild in the future. Maybe ARB has improved in the last 3 years but it still seems like a roll of the dice on how long it will last. After talking to my go to local shop whos done probably 100 of them, they're not fans since a lot end up leaking in a few years.

 

[jiggletits]

The issue seems to be in the design of an air locker mass produced for consumer install. As I understand the housing must be pressurized for them to work. For that reason, they are and always will be problematic. They are too complicated. ARB could probably just make their design electronic but on some level they are motivated to sell compressors too.

Does the e-locker require drilling? YES and they do leak. However, that leak does not affect functionality of the locker.

 

[Rednexus]

I think the ARB reliability is also affected by the overall system reliability. You have the compressor, relays, then air tubing to the locker, and the various internal seals. If any one of those components has an issues, pressure will not build and the locker will not engage.

For an e-locker where you just have a relay, wiring, and then the locker internals. Wiring is always more reliable than an air line and easier to fix/splice in the field (I carry spare wire and butt splices in my GX anyway). I also live in a wet/humid climate and have concerns with condensation and freezing. I have to drain a LOT of water out of my shop compressor on a routine basis, so it seems the ARB would also accumulate moisture in the lines. The last wheeling trip I went on it was 18F, sometimes I wheel when it is colder than that. Although I did not need a locker on that trip, had I it seems there could have been issues with freezing in the air lines.

I've gone back and forth between the two multiple times (mainly because they are the same cost when you add in the compressor cost, and I really want a good onboard compressor), and have more or less decided on the Harrop for my intermittent wheeling. I never want to open my diffs again, other than fluid changes, after I eventually do this mod.

 

[Dharma Dude]

The issue seems to be in the design of an air locker mass produced for consumer install. As I understand the housing must be pressurized for them to work. For that reason, they are and always will be problematic. They are too complicated. ARB could probably just make their design electronic but on some level they are motivated to sell compressors too.

Does the e-locker require drilling? YES and they do leak. However, that leak does not affect functionality of the locker.

How can the diff housing be pressurized? Don't all diffs have a breather tube?

 

[jiggletits]

I miss-spoke a little, the mechanism within the diff is what ultimately gets pressurized. If either the 2 o-ring seals within the diff fail, then you get a pressurized diff housing when you enable it, and a locker that does not work. That's two of many potential points of failure as mentioned by Rednexus.

Watch like minute 23 to 26 or so, he goes over installation of the o rings and where they sit.

 

[estoddart]

Do yourself a favor and return the air locker. Get the e-locker and save headache down the road when the air locker seals fail.

Every locking system has it's pros and cons. For me, having an e-locker fail in the LOCKED position requiring a late night of trail wrenching to be able to safely drive home on pavement (from Moab to Seattle) is a big con. It had to be manually unlocked and thankfully we had cell service to find the directions. It was a Toyota OEM e-locker.

If a rear air locker fails, you just stop having a locker and can continue to drive as you did before the install.

I really wanted the GX to have a front and rear e-locker set up like our old 80 series. I also had problems with those lockers every once in awhile.

 

[estoddart]

What size tires are you running? Curious to see if you notice any kind of difference vs stock once you install. Also, do you have a Sport package with KDSS, or are you going with no rear sway bar?

I'll post up in my build thread when it's done. We don't have KDSS and will run the same sway in the back. It just takes different sway bar mounts on the axle side.

 

[Rednexus]

If a rear air locker fails, you just stop having a locker and can continue to drive as you did before the install.

I really wanted the GX to have a front and rear e-locker set up like our old 80 series. I also had problems with those lockers every once in awhile.

The Harrop/Eaton e-locker is much more similar to an ARB than a Toyota e-locker in that regard. It uses an electromagnet to lock the diff. If something fails it will default to the unlocked position. It's probably more reliable than a Toyota e-locker too because the mechanism is much simpler (no actuator motor).

 

[HomersCanyonero]

I miss-spoke a little, the mechanism within the diff is what ultimately gets pressurized. If either the 2 o-ring seals within the diff fail, then you get a pressurized diff housing when you enable it, and a locker that does not work. That's two of many potential points of failure as mentioned by Rednexus.

Watch like minute 23 to 26 or so, he goes over installation of the o rings and where they sit.

The TJM air lockers work differently than the ARB air lockers. TJM has no internal o-rings like ARB. Too bad they don't seem to make air lockers for the GX470.

If I'm going to spend money on lockers, I want them reliable and maintenance free! LOL

 

[drowzyGX]

Trying to collect a list of parts required for this, and I know there’s a lot of options and variations possible.

Goal is to keep KDSS, and I know the 5th gen 4runner trail edition with kdss and e-locker is the “plug and play” unicorn for this. However, it’s hard to find that entire setup. I’m trying to piece it together myself, and want to make sure I’ve got the right parts in mind:

• Axle / diff housing (4211060B21)
• Third member with e-locker and 4.56 gears (ECGS)
• Front clamshell re-geared to 4.56 (is this the right one?)
• Re-use axle shafts / hubs / rotors / e-brake assembly

Is this accurate?

 

[jiggletits]

Trying to collect a list of parts required for this, and I know there’s a lot of options and variations possible.

Goal is to keep KDSS, and I know the 5th gen 4runner trail edition with kdss and e-locker is the “plug and play” unicorn for this. However, it’s hard to find that entire setup. I’m trying to piece it together myself, and want to make sure I’ve got the right parts in mind:

• Axle / diff housing (4211060B21)
• Third member with e-locker and 4.56 gears (ECGS)
• Front clamshell re-geared to 4.56 (is this the right one?)
• Re-use axle shafts / hubs / rotors / e-brake assembly

Is this accurate?

Why are you replacing housings? If you are swapping to an 8.2 all you need is third member. Unless you are running 35s the 8" is fine. You can order gears/bearing kits/e-lockers and have a local shop do this for a lot less money and effort. Justdifferentials seems to have best pricing and 5% off. Pretty sure they did not charge tax either, a lot of website are still not doing that.

If you have a local shop do it, you get a warranty and any issue with leaks, or otherwise (new gears may need lash adjustment after some break-in) will be much easier to deal with than removing your s*** and shipping it to ECGS.

 

[drowzyGX]

Why are you replacing housings? If you are swapping to an 8.2 all you need is third member. Unless you are running 35s the 8" is fine. You can order gears/bearing kits/e-lockers and have a local shop do this for a lot less money and effort. Justdifferentials seems to have best pricing and 5% off. Pretty sure they did not charge tax either, a lot of website are still not doing that.

If you have a local shop do it, you get a warranty and any issue with leaks, or otherwise (new gears may need lash adjustment after some break-in) will be much easier to deal with than removing your s*** and shipping it to ECGS.

not sure if I’ll do the mod or not, but I don’t want to invest in re-gearing the 8”. If I go that route, I’m going with the 8.2, not worried about the extra cost.

I can try and hunt down the full 8.2 from a 5th gen 4runner with kdss and re-gear it, but that’s hard to find. so I’m just trying to compile the list of parts.

I believe that the housing, the third member, the kit to re-gear the third member and the front clamshell, and then I can re-use my axles / rotors / e brake from the gx470

 

[jiggletits]

not sure if I’ll do the mod or not, but I don’t want to invest in re-gearing the 8”. If I go that route, I’m going with the 8.2, not worried about the extra cost.

I can try and hunt down the full 8.2 from a 5th gen 4runner with kdss and re-gear it, but that’s hard to find. so I’m just trying to compile the list of parts.

I believe that the housing, the third member, the kit to re-gear the third member and the front clamshell, and then I can re-use my axles / rotors / e brake from the gx470

Right, but you understand that you can move to the "8.2" diff without buying a whole new housing, right?

 

[drowzyGX]

Right, but you understand that you can move to the "8.2" diff without buying a whole new housing, right?

I don’t believe that is accurate. The third member can’t slot into the 8” housing on the GX. So, you need the entire 8.2” setup…

 

[jiggletits]

I don’t believe that is accurate. The third member can’t slot into the 8” housing on the GX. So, you need the entire 8.2” setup…

You can cut/tap the 8" to work, have to add a couple studs, and yes it does fit. Very minor cutting. It's technically a different housing but the difference is nothing major. The weak point is in the diff not the housing. I almost went this route but the 8" is just fine with stock gears and 32s.

'8.2"' is a misnomer. Both the 8" and the "8.2" are 8". Think of the 8.2 as more of an 8" version 2.

 

[drowzyGX]

You can cut/tap the 8" to work, have to add a couple studs, and yes it does fit. Very minor cutting. It's technically a different housing but the difference is nothing major. The weak point is in the diff not the housing. I almost went this route but the 8" is just fine with stock gears and 32s.

'8.2"' is a misnomer. Both the 8" and the "8.2" are 8". Think of the 8.2 as more of an 8" version 2.

At that point I’d rather spend the $750 and get the housing that’s designed specifically for the third-member.