Front or Rear locker?

I am considering getting a locker but can't get past a crucial question. Front or rear locker. I figured I'd ask the group. Ant advantages or disadvantages? What gets better grip? The weight is in the front (engine) but also not sure if the front locker stresses the IFS. Thoughts?

 

Rear first because you have the advantage of 2wd locked. Both would be ideal but $$$$$.

 

Thats a great point. Didn't know I could lock it on 2wd.

 

Well it's aftermarket so you can lock it whenever you like it. Toyota limits locker use to low range because the driving characteristics change when a diff is locked.

 

OP, what 4Runner model do you have?

I’m not trying to be a butt but it’s a fair question…. Why do you think you need a locker? Are you presently unable to go places with your rig “as is” that a locker would enable it to go?

FWIW, Toyota’s A-Trac system simulates a locker by engaging the ABS system to manage wheel spin and can get you 90% of the places you want to go. I have a rear locker on my TRD OR and have yet to need it for the moderate to intermediate trails I have been on.

Cheers,
Bob

 

If I was seriously considering locker(s), I would first visit some of the typical trails that I might encounter and see how the truck performs.

Only speaking for myself, but I would be disappointed to spend thousands of dollars for a system that will never get used.

 

We go on trails all over the mountains, but we don’t seek out rock crawling. We have never been in a situation that we NEEDED to have a locker. Even while it was all out and apart for a regear we didn’t bother with lockers.

 

I have an SR5. I do a lot of off roading here in Colorado. Almost every weekend and I have been in situations where A-Trac was either not enough or barely after smoking the tires some. So I understand your point but I'm one of those that understand its limitations due to experience.

 

To be clear, I am considering one, not necessarily getting one. Its darn expensive. Just playing with the idea and wanted to know if there was input regarding pros and cons of a front or rear locker.

 

The "trails" you drive on must be pretty smooth then, with no washouts crossing them. At least around here I find myself with one front tire and the opposite side rear tire hanging in the air with no traction. No locker, no go further. Locker, no problem.

I don't do rock crawling either, just our standard mountain roads that are "graded" by water running down and across them.

 

Plenty of examples of the ATRAC capability. It just doesn’t have the cool factor of lockers.

https://m.youtube.com/watch?v=6ARYqd9lQRo&pp=ygUbNHJ1bm5lciBzcjUgb2ZmIGNhbWJlciBkZW1v

 

ATRAC is useful but it can overheat and disable itself if it's used too much. A locker will not. I had front and rear lockers on my Tacoma and it was pretty unstoppable as long as you're going in a straight-ish line. Rear locked and front open was much more usable for most situations. If I had to do it all over again I'd probably skip the front locker.

 

My cousin has a 2nd gen tacoma SR5. No lockers. No ATRAC.

He lives on a dirt road and gets snow. Said road doesn't get plowed. He's never been stuck in his tacoma. It's gone everywhere My 4runner has no problem. He only puts 4wd on when he has to which has only been twice in all the times I've been out with him. His truck WAS stock up until 6 months ago.

I think the suggestion to go take it out and see if you need it is best.

 

It sound like you’re super hardcore trails have run of the mill obstacles that you don’t know how to navigate

We had the 4Runner on the left rear and right front tires teetering back and forth between which other wheel touched down on the rock and with ATRAC it walked right off without a problem. If you need a locker for a washout that hangs a wheel it’s a driver mod you need, not a locker.

 

I never get tired of this video

 

In his defense, I felt tippy trying to cross a washout in a '97 explorer back in the day. I asked the passenger to get out in case I rolled and she freaked out and said my rear wheel was over a foot off the ground. I put it park, shoved the parking brake to the floor and got out to assess the situation. There was no crossing without rolling.

I ended up stacking rocks into the washout so I could get across and straddle it the rest of the way down

 

I got 2WD rental sedans to backcountry trailheads countless times by stacking rocks. I hope there's less of that in my future, but if that's what it takes, I'm all in.

 

I think it’s better to get a rear locker if you’re only going to get one. Seems to me a rear locker will be more mechanichally forgiving. A front locker makes the cv axles take the stress of propelling the vehicle, and adds the the stresses imparted by steering. I’ve seen videos of toyotas with front lockers breaking CVs when they get bound up by large steering inputs. Haven’t seen any videos of rear axles breaking. It's probably the reason toyota offers the locker in the rear and not the front.

Also, loss of traction, even when due to having a wheel in the air, will more negatively affect you going uphill. The weight on the back will probably give the rear end more ultimate traction. The front will be unloaded, and both wheels could struggle for traction.

i don’t see what the benefit of a front diff being the only locked diff.

 

Lockers are proactive. A-trac is reactive. Lockers prevent wheel spin. ABS-based traction control requires it. ABS traction control is (mostly) idiot proof. Lockers are not. You have to know when to use them, and when not to. The rear axle is more robust than the front axle. If there’s only one locker it should be on the rear.

 

I thought for a looong time about getting a rear locker. After 2 trips to Moab, 3 to Tenn. and the little wheeling we have around Wis., A-Trac just plain works. Some trails "require" a locker, but the A-Trac just does its' thing. I've walked up obstacles that my locked buddies had issues with. I used the locker money for a rear bumper.
Understand that the A-Trac needs to spin the wheels a bit (not fast, high rev burn-outs. Just a little bit to get the tires spinning.) so the 'puter can decide which wheels need braking.

 

I’ve had the privilege of doing desert trails, that consist of deep moon dust (like dry quicksand) and large sharp bolder fields. I’ve never needed anything other than 4H. I guess I don’t qualify as a hardcore off-roader or overlander. I don’t even have any patches on my headliner. I’m not even sure if my ATRAC works. Never needed it.

My investment has been in tires. That’s where the rubber meets the road (pun intended).

 

Start with a rear, but if you're planning a gear ratio swap in your future, then consider both. Worried about a cv axle? Carry a spare and learn how to replace it. I bet you could do it in an hour or less if you're any good with tools.

 

Locking diffs are just a tool. Tools make doing certain things easier. But it doesn’t mean things can’t be done without a certain tool if you use a little sense and creativity.

 

Front.

 

You guys who would do front first/only: can you please explain your reasoning?

 

To simply put it. The front pulls you through or out of.

There's plenty of debate over front or rear locker, but if I was building a true offroad vehicle it would have both front and rear.

 

I went with both front and rear.

 

I can tell you have zero experience with lockers if you say front first.

 

Imagine if the new TRD OR came with a front locker only, people would think Toyota lost their mind.