Front Locker Question

[crawler#976]

Congratulations on getting an ARB!

You can turn off an ARB at anytime, but, that doesn't mean it will disengage immediately. If it's in a bind you may have to roll forward or backwards to release it.

I'd recommend just going out and playing with your ARB carefully, and learn what to expect.

With an ARB that acts exactly the same as a spool when locked, you must pay a little more attention to how you tackle things. I had front and rear spools in my old trail beater, so I'm familiar with how they work (I drove the truck for over 50K). Since I had the luxury of using dual cases, and I couldn't turn off the front locker, I shifted between 4x4 and 2x4 a lot. I could stay in 2x4 low range between obstacles. If I needed to climb over something, I engaged 4x4 and always tried to plan my line to avoid any turn that required anything close to full lock to lock turns. Do the same with the ARB - on when you need it, off when you don't. Don't be afraid to turn with it on, just be careful to apply just enough power to get you moving. Back in the day, it was called rock crawling for a reason - slow and steady was the best way to go, and I still believe it works just as well now as it did then. The current rage of rock racing is extremely hard on parts...

With front and rear lockers engaged in any type of off camber loose terrain, even if it's only slightly off camber, you will tend to move down hill almost as fast as forward. If it's not off camber you will tend to go straight forward regardless of where the front tires are pointed, especially in mud and snow.

Mark

 

[madizell]

You can turn the ARB on and off at will, but remember that the dog gears have to mesh and disengage, so it is something like shifting a transmission without using the clutch. You might have to back off or goose the gas a bit to take pressure off the gears. Otherwise, ARB engages and disengages more or less immediately. There is no technical reason to stop to engage or disengage as there is with most of the factory installed E-units that are computer controlled.

Can you use it to gain traction when slipping: I would say a qualified maybe. Assuming that one but not both front wheels are slipping, engaging the locker while slipping will probably just cause both wheels to slip because for the front to be slipping at all, the rears would almost have to be slipping as well. By that point, you are toast to start with. Better to engage before you try running up that slippery hill, and going lighter on the gas. Adding the locker to the equation won't dramatically change your ability to overcome lack of traction. However, if one tire is on dry land and the other is slipping, then perhaps it will make a difference, but if you engaged first, you would have driven right over the problem without noticing it.

Regarding tie rods, you are more likely to bend rather than break stock tie rods. A front locker can add to the stress, but only if one or both tires are in a bind to start with, like jammed between rocks. Here, your brain has to be in charge. If you are climbing between rocks, don't twist the steering wheel back and forth with abandon, especially if sitting still. You can bend almost any tie rod that way, and if the rod is strong enough not to bend, the ends can break, as can the steering knuckles. I would not expect the locker to add greatly to the risk of bending or breaking a tie rod under normal trail conditions. You can upgrade, but there is no end to the upgrades. First the tie rods, then heim joints, then a steering brace, then a stronger steering box, then a better pump, then a cooler, then ram assist, and if you do all that, you should probably also add longer suspension arms, coil overs and so on. By that point, you have already passed the overkill line. I would try it the way it is, because if you rarely use the locker and mostly only to go straight ahead, your tie rods will be fine.

 

[tdesanto]

Thank you again, gentlemen. I really appreciate the feedback.

 

[devinsixtyseven]

I asked a similar question here a year or two ago, received some good advice and thought I'd pass on my own experiences since getting a front locker on my own IFS vehicle.

I've found my front locker indispensable in snow and mud. I've been able to safely make several climbs up slop- or snow-covered hills which were simply impossible with open differentials and all-terrains (or center-ribbed tires). Certainly no rock crawling, just low traction. Having both differentials locked and making a controlled climb up a relatively straight road with one side on dry, stable ground made all the difference in component wear and nerves. I've done similar things on snow. Having climbed out of Mineral Bottom on a sloppy, partially snow-covered road using open differentials, and having climbed Pucker Pass on snow and ice with a pair of lockers, I'd never go back to open differentials.

Frankly I'm amazed my girlfriend still gets in the truck with me, after those two climbs.

My ARB also likes to stay bound for a moment or two. Usually a bit of wiggling of the steering wheel opens it.

I'd opine that the majority of rough terrain you'll see with an expedition-style build will be surmountable with only a rear locker, the front is simply a bit of insurance for snow and muck. I've been in several situations where low tire pressure (10#), low range and a rear locker were insufficient, and the front locker really made the difference between a successful climb in Spring thaw, or turning back.

It's also worth mentioning that exceptional tires may preclude use of either locker...in other words, run a set of tires appropriate to the worst you'll see on a regular basis and are capable of handling with your equipment. I've been denied with both lockers and tires at 10# when a buddy with larger rims, higher pressure and better tread made the climb with a drop-in rear locker. Tires do make a huge difference, sometimes more so than lockers.

Every report of broken parts I've ever come across has resulted from rock crawling attempts that were simply beyond the ability of one axle to take the entire load. Unfortunately that's vehicle-specific, but the rule of thumb already posted--use sparingly and leave off when unnecessary--will keep the truck in one piece regardless of make/model.

May as well carry a complete halfshaft assembly, greased and ready to go. Even if you only need an inner joint, it'll be cleaner to swap the entire axle and deal with the broken pieces in camp. If you're carrying an axle, don't forget all the little things you'll need to make the swap...jack stand included.

Happy trails, and welcome to capability :sombrero:! As with everything, don't abuse it and it'll work out great.

-Sean

 

[tdesanto]

Thanks for the information.

 

[daverami]

I've followed this thread and the information has been great. I also have a question regarding a front locker. My 2006 Tacoma has the open front, and an LSD in the rear. Eventually, I would like to get an ARB for the rear, but I was thinking that, possibly, an ARB in the front, in addition to the current LSD in the rear, would help get out of any iffy spots when necessary. Does this make any sense!?

 

[michaelgroves]

I would imagine that an ARB in the front, and a LSD in the rear would be better than an ARB in the rear and an open diff in the front. Am I right in saying those are the two options that are being compared?

Ideally, an ARB in each axle would be the best, IMO. The ability to have a fully locked diff when you need it, and a fully unlocked one when you don't, is why a manual locker like the ARB is the best way forward, if cost isn't an issue.

 

[Crikeymike]

Since you already have some form of a traction aid in the rear (LSD), then an air locker in the front is a good choice. It really depends on what terrain you drive on though, because with my front and rear lockers, I use the rear every time offroad (where I go), but rarely use the front. That's because with the rear 100% locked, I normally get thru whatever I'm trying, and I don't need the front.

Some people in the past have pulled their LSD, installed an ARB, then sold the LSD to pay back some of the costs of the ARB.

An ARB in the front would really pull you out of some "iffy" spots though. When I use my front, it makes a huge difference.

 

[tdesanto]

I would imagine that an ARB in the front, and a LSD in the rear would be better than an ARB in the rear and an open diff in the front. Am I right in saying those are the two options that are being compared?

Ideally, an ARB in each axle would be the best, IMO. The ability to have a fully locked diff when you need it, and a fully unlocked one when you don't, is why a manual locker like the ARB is the best way forward, if cost isn't an issue.

If these are the only two options available. I would second this opinion. Having the ARB in front and the LSD in the rear is better than open front/ARB rear.

This is what I have now. As soon as ARB makes the rear locker for my truck, I will then switch out my LSD for the ARB. But, in the mean time, I find the combination quite good. BTW, I continue to be impressed with how quickly the ARB engages/disengages.