Add factory rear locker to 2007 100 series? (2 Viewers)

[Fisher67]

Just added a winch to my truck and was thinking that was the final project to pursue. Have really been impressed b the ATRAC system and having learned to use it correctly, thought it would be all I need. Having been told that the 100 series Achilles heel is the front differential, I started to think about adding a locker. Once I started to research that option, I heard plenty of opinions that 1) a front locker does not really add that much benefit without a rear and can affect steering and 2) the front differential on my 2007 is much stronger than the 2 pinion earlier versions, making it less likely to grenade.

Since I bought a Viair portable compressor and don’t want to buy another to power ran air locker, then i started to look at Harrop elockers. Heard a sentiment that they would not do much good, as they had to rotate a full rotation before getting locked, which was bad if you were already stuck. isn’t this concern only if you had not engaged it before attempting the obstacle?

Finally, I saw the blank plate in the truck where the factory locker switch would go and wondered if there are still factory rear lockers that I could install and have the benefit of a rear e-locker, while maintaining the benefit of ATRAC?

Not looking to have a serious rock crawler, but want to have all potential tools to allow me to tackle more advanced trails in CO. Have been exploring and done Kingston Peak, Jenny Creek, McClellan mountain, and Red Cone. Red Cone and Jenny Creek were the two diciest trails where I though I was getting to be over my head, but was with a group on Jenny Creek that helped me get through the worst patches. Red Cone was flat out scary and I thought i was stuck several times, but managed to rock my self out with just damage to the rear bumper and rear LCAs.

Appreciate any thoughts you can provide in helping explore this idea?

Thanks,

Todd

 

[saucebox]

I'm doing the same thing right now—most of the information you'll need is in a really good thread by @sdnative Adding F/R lockers to 2003 Land Cruiser. At a minimum, you'd need the locking third and the short side axle shaft.

TL;DR: you'll have to grind down your housing some (not terribly difficult) and re-gear your front to match. And come up with a wiring harness. There are a couple of aftermarket options (Slee, Low Range Off Road) to simplify that some if you don't have access to the factory parts.

I've heard nothing but good things about the Harrop for the front, but it was a little out of budget for me now.

 

[Fisher67]

I'm doing the same thing right now—most of the information you'll need is in a really good thread by @sdnative Adding F/R lockers to 2003 Land Cruiser. At a minimum, you'd need the locking third and the short side axle shaft.

TL;DR: you'll have to grind down your housing some (not terribly difficult) and re-gear your front to match. And come up with a wiring harness. There are a couple of aftermarket options (Slee, Low Range Off Road) to simplify that some if you don't have access to the factory parts.

I've heard nothing but good things about the Harrop for the front, but it was a little out of budget for me now.

Thanks for the link. Read through the posts and realize that I should have been more clear. I lack the technical skills to do this myself and would take it to Slee who had done most of the additions so far. Putting in a CB and antenna, yellow box and a BT-45 radio interface has been as much as I am confident to do myself.

I was primarily looking to people who are knowledgeable about this to weigh in if this was possible and if so, what would be the cleanest way to get it done?

thanks,

todd

 

[gungriffin]

Thanks for the link. Read through the posts and realize that I should have been more clear. I lack the technical skills to do this myself and would take it to Slee who had done most of the additions so far. Putting in a CB and antenna, yellow box and a BT-45 radio interface has been as much as I am confident to do myself.

I was primarily looking to people who are knowledgeable about this to weigh in if this was possible and if so, what would be the cleanest way to get it done?

thanks,

todd

I believe that you will find it easier and cheaper to just go with an ARB or Harrop locker. Are you going to be sizing up tires? This is often the time that people just go all in and do F/R lockers and regear the diffs to 4.88 and then go with larger tires.

 

[Fisher67]

Ryan,

the tires I have on now are 32.6” and I like them. Maybe go to the next size larger 33” and narrower, but don’t want to ditch the AHC and cant see running much larger. Would I have to modify things to run the original factory rear locker, which is why you suggest a Harrop? Don’t want to buy an ARB, as I would have to buy onboard air, and I already ponied up for the Viair portable compressor.

thanks,

todd

 

[Bardiya]

It's possible. We do it here in the UAE. Complete axle housing swap with the wiring, diff ecu, switch and dash light. ~1300$

 

[geanes]

Well, whomever told you the Harrop needs a full rotation to engage, didn't know what they were talking about. Harrop are solid lockers that don't require air pressure to be maintained in order to stay locked. ARBs are solid as well, but have scattered cases of air leaks. Not very common, but something to be aware of. I have a 98 with the supposedly "weak" 2 pinion diff. It's been plenty strong for me running rugged trails all over west TX, NM, CO and UT. I don't currently run a front locker, but will do so if and when the front diff ever gives out. I don't even have ATRAC (which is excellent BTW). Learn to manage the throttle, avoid excessive wheel spin and you'll be fine. Having said that, a rear locker is damn nice.....especially in off-camber ruts. Instead of having to use speed/velocity in a non-locked, non-ATRAC vehicle or heavy throttle in an ATRAC (needed to get it operating), flick the switch and simply and slowly crawl right through the obstacle. No trail damage, no damage to the rig. My rear locker is a Harrop and replaced my factory LSD. Having the rear has allowed me to be much smoother on trails and not run into issues where I have to "send it" to get through. That's usually what leads to grenaded diffs. I'd learn to drive with ATRAC and spend the money on other necessities. If you find yourself getting deeper into off-roading and getting on rougher, more rutted trails, then consider putting in a rear locker. I wouldn't consider a front locker unless either A) you grenade your existing front diff (very unlikely) or B) you decide to regear at which point might as well add it since it's the same labor either way. If you pick a locker, stick with either Harrop or ARB. Both (as with anything) have their very minor drawbacks. But neither have drawbacks that necessarily effect us overlanders. If you're going to slice and dice your rig into a true rock crawler, then the discussion changes.

As for the switch gear, just get the OEM dial switch which fits right in the blank. You can even get the 80 Series dual switch which does Rear only and Front/Rear combo. Looks clean and OEM.

 

[TTCruiser]

Still sounds like it would be easier to buy the single ARB compressor and run ARB’s front and rear. Keep the Viair compressor for airing up quickly.

 

[Captramrod01]

Your cheapest option will be single ARB compressor and paying a local shop to install the locker. Elocker axle swap will require regearing or swapping the front diff too. If you are not doing this work shop labor will easily eclipse just throwing the single ARB in the rear.

 

[SlowBuild]

@geanes has good advice. Just wait on it.

In future, it sounds like you prefer so stay away from an air locker. If you reconsider I would look at TJM. I chose TJM for greater reliability and longevity over ARB. Harrop seems to be the current favorite lately.

 

[gungriffin]

Ryan,

the tires I have on now are 32.6” and I like them. Maybe go to the next size larger 33” and narrower, but don’t want to ditch the AHC and cant see running much larger. Would I have to modify things to run the original factory rear locker, which is why you suggest a Harrop? Don’t want to buy an ARB, as I would have to buy onboard air, and I already ponied up for the Viair portable compressor.

thanks,

todd

I was just trying to figure out if it was worth it to regear for you while you are installing lockers. If you were installing lockers f/r, this is when most people would add the regear becuse it wouldn't cost much more for install costs. At 32.6", it is not worth regearing.

I believe that it will be less expensive overall to just start with a new locker of your choosing than going with a factory setup. Especially because the gearing will be different between the two.

 

[ENGINE er]

when my 98 caught fire, i moved over the front TJM airlocker/regear diff and rear electric locker regear diff to my 06 LX470.

super easy. Wiring is the hardest part but slee makes a harness to use the factory 80 switch to control all of it. I think i had to drill a hole for a bracket too.

 

[gungriffin]

when my 98 caught fire, i moved over the front TJM airlocker/regear diff and rear electric locker regear diff to my 06 LX470.

super easy. Wiring is the hardest part but slee makes a harness to use the factory 80 switch to control all of it. I think i had to drill a hole for a bracket too.

Were you able to keep the 4.3 diff gearing from the 98? That actually seems like it would be ideal for a ~33" tire with the 5 speed.

 

[suprarx7nut]

Forget the sunk cost on the portable compressor. That's a fallacy. Focus forward and do what makes sense from here on out. Don't drop $2k+ on something that's not ideal just to make yourself feel better about a previous purchase.

As someone that's wheeled extensively with the factory e-locker, I'd go ARB. The factory locker is nice, but it does not always engage when you want it. It can take seconds, even minutes to engage - meanwhile, you might be spinning tires. The ARB engages immediately. The Harrop, from what I recall, has a drawback where it can disengage when you change motion forward to reverse. It will not engage again until you rotate the tires enough to hit the next pin lock location in the diff. I think that's the rotation thing you've heard about. No idea how big a deal that actually is, but it's often cited so I think it's significant.

I vote a single ARB compressor and ARB air-locker. If you are comfortable with craigs and the like, sell that portable compressor and spring for the big boy dual ARB compressor and enjoy luxurious, permanent on board air.

 

[geanes]

The Harrop, from what I recall, has a drawback where it can disengage when you change motion forward to reverse. It will not engage again until you rotate the tires enough to hit the next pin lock location in the diff. I think that's the rotation thing you've heard about. No idea how big a deal that actually is, but it's often cited so I think it's significant.

It's less than 1/16th of a rotation to engage if changing from forward to reverse. Again, only when changing direction. If your going forward, stop, engage the locker and keep going forward, the engagement is instant. Really only a big deal to rock crawlers who can't have any "play" at all. I think that's where the complaints by and large come from....dudes in rock crawlers doing stuff my 100 has no business ever trying.

For overlanding and what we do with our heavy rigs, it's not even an issue. Mine instantly locks the moment I turn the dial. I haven't noticed anything negative about it frankly. Definitely love ARB products for the most part. Just didn't want to run air actuated lockers that can come disengaged if pressure drops suddenly. Granted, that's a very rare scenario, but IMO similar to the concern about the very slight rotation required for the Harrop to engage.

Ward Harris wrote the following just recently:

"Unlike factory elockers, these units may briefly disengage when reversing direction, but the actuation cycle is quick, if it happens at all.

Most of those Harrops sold have been rear axle installs, somewhere around 70%, I think, including many 200s. No complaints and lots of happy customers/owners. I have had rear Harrops in my Tacoma and a Corvette powered BJ73 - they worked as advertised - and I have one going into my new driver, a GX460 with 8.2" diff.

Harrops and ARBs are comparable, not identical. They are similar, but different. Do your research and look at the facts of actuation mechanism, service issues and cost. Yes, Harrops cost more, but in 8 years of production, they do not require service or repairs."

Here is one use case example where the e-locker "disadvantage" might come into play:

"Example would be when I’m in crazy rocks, flexed out to the max, really off camber. If I need to back up to take a slightly different line, and my rear axle is only on one tire, the last thing I need, is to have the tire on the ground no longer get power for a half rotation of the differential and then suddenly reengange. While on some crazy balancing act on bigger than the truck rocks."


I think the general consensus from the experts is that the ARB and the Harrops are the class leaders with each performing very well with very minor issues. I don't think you can go wrong with either one frankly.

 

[Fisher67]

It's less than 1/16th of a rotation to engage if changing from forward to reverse. Again, only when changing direction. If your going forward, stop, engage the locker and keep going forward, the engagement is instant. Really only a big deal to rock crawlers who can't have any "play" at all. I think that's where the complaints by and large come from....dudes in rock crawlers doing stuff my 100 has no business ever trying.

For overlanding and what we do with our heavy rigs, it's not even an issue. Mine instantly locks the moment I turn the dial. I haven't noticed anything negative about it frankly. Definitely love ARB products for the most part. Just didn't want to run air actuated lockers that can come disengaged if pressure drops suddenly. Granted, that's a very rare scenario, but IMO similar to the concern about the very slight rotation required for the Harrop to engage.

Ward Harris wrote the following just recently:

"Unlike factory elockers, these units may briefly disengage when reversing direction, but the actuation cycle is quick, if it happens at all.

Most of those Harrops sold have been rear axle installs, somewhere around 70%, I think, including many 200s. No complaints and lots of happy customers/owners. I have had rear Harrops in my Tacoma and a Corvette powered BJ73 - they worked as advertised - and I have one going into my new driver, a GX460 with 8.2" diff.

Harrops and ARBs are comparable, not identical. They are similar, but different. Do your research and look at the facts of actuation mechanism, service issues and cost. Yes, Harrops cost more, but in 8 years of production, they do not require service or repairs."

Here is one use case example where the e-locker "disadvantage" might come into play:

"Example would be when I’m in crazy rocks, flexed out to the max, really off camber. If I need to back up to take a slightly different line, and my rear axle is only on one tire, the last thing I need, is to have the tire on the ground no longer get power for a half rotation of the differential and then suddenly reengange. While on some crazy balancing act on bigger than the truck rocks."


I think the general consensus from the experts is that the ARB and the Harrops are the class leaders with each performing very well with very minor issues. I don't think you can go wrong with either one frankly.

That is great info and maybe what I should pursue. Any sense of the cost to do the Harrop rear locker? Will I need to change any gears in the rear diff as well? You are running the size tires I might go to when I have worn the 285 65 18s out. I installed a yellow box to fix the speedo discrepancy and have only noticed a difference when I charge up I-70 to go through the tunnel at Eisenhower and watched the RPMs stay a little higher than when I was running stock size tires.

if it is around a $1500 job, then seems like a good insurance policy if I need a little extra traction.

thanks,

todd

 

[saucebox]

That is great info and maybe what I should pursue. Any sense of the cost to do the Harrop rear locker? Will I need to change any gears in the rear diff as well? You are running the size tires I might go to when I have worn the 285 65 18s out. I installed a yellow box to fix the speedo discrepancy and have only noticed a difference when I charge up I-70 to go through the tunnel at Eisenhower and watched the RPMs stay a little higher than when I was running stock size tires.

if it is around a $1500 job, then seems like a good insurance policy if I need a little extra traction.

thanks,

todd

The Harrop is around $1200, and the remaining parts and labor will likely stretch you to $2K, if not a tiny bit more.

 

[ENGINE er]

Were you able to keep the 4.3 diff gearing from the 98? That actually seems like it would be ideal for a ~33" tire with the 5 speed.

I had regeared the 98 to 4.88 before the fire, so my 06 LX has 4.88 and 33s and its great. Feels quick even with the million pounds of s*** bolted to it.

And as far as the e locker/air locker debate.

@duggy cleaned up and freshened my actuator earlier this year and its never been faster or more reliable. its NOT as fast as the front air locker but when i hit the switch now im confident it will engage when i need it.

 

[OEMGUY0720]

Can anyone confirm the correct ARB part number for an 06 LX?
• ARB-RD131 - for front (?)
• ARB-RD152 - for rear (?)

Thanks,
Paul

 

[Hulsty]

Check the ARB catalouge.