Atrac aint up to the task.. Locker choices?

[fromLRtoT4R]

Coming out of a Land Rover (Gen 3 and 4), I was actually able to rely on the terrain response (traction control) system to get me though anything.. Those things really don't need a rear or front locker, thay actually work.. That being said, their electronics reliability is questionable, and if that goes or if the modules get wet, you are hiking back home.. Not to mention the air suspension that can bust a leak while on a trail..
Now I have an 07 Runner.. I still have my LR4 but its now a family car and I will no longer abuse it like I used to.. Anyway, Got my 3" front, 2" rear lift, coils, shocks, the works.. Suspension is fine, but the Atrac system leaves much to be desired. In my opinion its slow, clumsy, just not at all up to the task. It actually cant do one fourth the stuff the last 2 generations of LR discos can do, but I bet its reliable!
After a few tests, I know 100% I need a locking diff.. At least for the rear axle for now..
From what I see, ARB has an air locker and Yukon has a locker.. Does anyone know of any other choices? I know the ARB is awesome, but $1000 locker plus air compressor is a bit pricey.. does anyone have experience with the Yukon or anything else?
Thanks for the help.. By the way, my dissatisfaction with the Atrac system is by no means an attempt to dis Toyotas.. just being honest and stating my opinions

 

[Mike07SE]

Check this out. Should help you out:

http://www.toyota-4runner.org/engin...196101-locking-differentials.html#post2013566

 

[CXS]

Can you give an example of what you're finding it can't do that your Land Rover does with ease? Just curious since I initially was very disappointed with my 4Runner after coming from a Land Cruiser.

 

[fromLRtoT4R]

Can you give an example of what you're finding it can't do that your Land Rover does with ease? Just curious since I initially was very disappointed with my 4Runner after coming from a Land Cruiser.

Glad you asked!From what I can tell, the land rover system is very quick to begin with.. It catches the slipping wheels much much quicker, immediately really.. and in a very smooth way rather than what atrac does which tries to stop those slipping wheels in a much slower and more violent way over and over again and in a much less effective way. If you only have one wheel in the air, atrac is ok.. two wheels in the air crawling up a steep dirt trail, your done with atrac.. It just digs and digs in pulses much like you would with your hands.. land rover on the other hand, does not do that.. you hear some very quick abs action and all of the sudden that beast of a vehicle just starts to move, you can't believe that it is actually moving with two wheels way up in the air, up a slippery rutted dirt hill, but it does... and the things in can do in very slippery mud is just ridiculous.. you think you are about to bury your wheels in deep mud, and all of the sudden after you put it in mud and ruts mode, and it just starts to move.. plust the suspension is pretty awesome too.. very smooth, great flexibility and articulation, just that pesky air bag thing makes it a little scary.. I am in the auto business and get to try out a lot of cars and always make a mission to try out the 4wd systems especially ones that dependent on traction control.. what land rover has done is just insane.. nothing simply comes close. but land rover is like a super hot girlfriend that you should never marry.. you really want to love her, but you can't really depend on her for the long haul.. hence my switch to 4runner for trail duties.. she's not that good looking but put her on a diet, put on a little make up and a nice dress, and she isn't so bad.. plus she'll stick with you

 

[CXS]

Nice analogy!

I've never driven a Land Rover so I can't speak to your observations though I'm sure you're accurate. Are you locking the center dif? What rpm's? I know when I made the switch I was disturbed by the abs racheting, noise, etc until I was told it was normal. I found I was over-reving in snow defeating the traction control, once I backed off it moved effortlessly through deep snow off-road.

This may be useless as it sounds like you know what you're doing and have experience under your belt but fogured it ws worth a mention.

It looks like you're in AZ, you have mud?

 

[fromLRtoT4R]

yep.. center locked.. start with low rpms, then give it progressively more and more throttle.. it just shakes until atrac is defeated completely. you cant defeat land rovers system unless you start pulling plugs and wires.. live in southern arizona.. sonoran desert which is the wettest desert in the world.. plenty of mud!

 

[CXS]

That doesn't sound right, keep in under 3k and it should work fine. There might be an issue if that doesn't work that way.

Never been to southern Az, good to know!

 

[RaceTRaCk]

I love the Atrac system in my '04. You are correct in a sense that it is slow to response, I only find it this way during super slow rock crawling speeds. Its gotten me through some really nasty terrains however. What I learned about it is it will do its job effectively with lots and lots of droop. I tried out 26", 27" & 28" rear shocks, and they are night and day difference in performance.

I went with a Yukon locker and love it, No switches or air lines to leak. Had to adjust the driving a little bit. No plans to lock the front.

http://www.toyota-4runner.org/4th-gen-t4rs/208730-yukon-grizzly-locker.html

 

[T4R2014]

Terrain response is the best. I love these newer Discos.

I think an FJ Cruiser e-locker rear axle can swap in. Wiring is another story.

 

[Oneluv13T4R]

I'm rockin a Spartan Locker ...
(made by Yukon)

 

[SSt4r]

Another option is the Detroit TrueTrac. Not a real locker, but supposed to work well with the Atrac.

 

[RonJR]

Another option is the Detroit TrueTrac. Not a real locker, but supposed to work well with the Atrac.

Makes sense. The Truetrac sends about 3x the torque to the slow wheel as to the fast wheel, vs. equal amounts with an open diff.

If you were in a situation where you needed 1000 ft-lbs of torque on the wheel with traction in order to move, with an open diff the ATRAC would have to apply 1000 ft-lbs of braking torque to the spinning wheel to accomplish that. With the truetrac, the ATRAC would only have to apply about 330 ft-lbs of braking. Seems like that should help it work better and be more responsive.

Nice thing about the truetrac is it's easy to install, not too expensive, and absolutely un-noticeable on the street. You could put truetracs both front and rear for less than the cost of an arb.

 

[Mike07SE]

Hopefully the link I listed provided useful reading material. I run the Detroit TT in the back of my truck and love it in all terrain. Seamless on the road in normal driving, but will also show itself when traction gets limited. I also run the ARB locker in the front as it was only option at the time (and believe it still is), but had there been the ability to run a TT up front as well I would have.

 

[CAN-03runner]

Hahaha. :violin::violin::violin:

You can't come onto a 4Runner forum and tell us you got an LR4 with 2 wheels in the air and not get this.

:worthless:worthless


Pictures or it never happened.

 

[CAN-03runner]

What tires are you running. Stock tires are pretty awful.

ATRAC runs best at 2000 RPM with a little momentum. If you start off, and you're confident you can clear everything and just get a good start, keep it at 2000 RPM it's quite impressive, it just doesn't stop. But it needs to be smooth if you just jab the gas on and off it's not effective, it has to be steady gas, steady RPM. If you stop and try to start again often you are done for. If you climb up onto a ledge and stop to assess your positon there and try to start again, often you are done for. If you take a Toyota into the bush you will be able to come back out. You can take a Landrover into the bush, but will you come out...LOL.

ARB is what to get. I've got ARB in my 1st Gen and dual ARB in my 4th gen. Doing it again I might have gotten auto lockers in the 1st gen. But it's a trail only , mostly trailered machine. On the 4th gen, especially your 2007, it's too nice and new to lose drive-ability. Also the ARB solidifies the carrier.

An elocker, is not worth the price, it costs the same as an ARB. You will need to get a housing that has a notch for the elocker motor or cut yours, it is more finicky than an ARB, and it doesn't solidify your carrier.

It could become cost effective if you are able to get the entire rear end off an FJ Cruiser for dirt cheap.

If you can offroad and abuse an LR4 don't balk at a 1000$ ARB locker

 

[BlackWorksInc]

I've been having some poor performance with my ATRAC for a bit now as well, though I'm fairly confident my issue is related to the fact the brakes are a bit glazed up and not gripping as well as I would like.

It's a finicky system with more than one wheel in the air I've noticed as well, but it does work better in the 2k RPM range.

 

[Burnzy]

I've never had a Land Rover. I have had my 4Runner for 2 years and have wheeled it a decent amount but still have much to learn. One thing I figured out quickly is that ATRAC works amazingly well if you go light on the skinny pedal. I haven't been stuck yet..... I am sure I will at some point in time the more I take it off road. Here's a short clip of me going up a 20ft mud and water covered rock face... ATRAC worked great, STEADY throttle and SLOW.There were plenty of Jeeps that had to try multiple times before they made it up.



https://m.youtube.com/watch?v=hDVOePFUxQU

 

[Tooltime19]

I too find that the A-Trac is happier while the vehicle is in motion not stopped. I try to keep some momentum whenever possible and I feel it works better. Although when rock crawling you cant always keep the vehicle moving with momentum which makes it a little harder. Also if you drive with two feet when rock crawling this helps a little too.

 

[RichN]

Another option is the Detroit TrueTrac. Not a real locker, but supposed to work well with the Atrac.

I'm not seeing the TrueTrac listed for 4th gen 4 Runners. Do you have a part# that fits? What mods have to be done to make it fit?

 

[sean2202]

I found that using a-trac is like learning an entirely new 4wd system from conventional 4wd with say rear locker. In the past it was just hammer down or engage disengage locker for condition terrain. A-trac is steady throttle under 2200 rpm and it will pull you through like a crawl control. I am still learning about using the brakes with the system as well. There is some great videos on u-tube crash course stuff a-trac related. IMO a land rover should be compared to a LC not a 4runner as I imagine the land rover costs quite a bit more than the 4runner so possibly more refinement ex. bells and whistles.