What kind of 4WD system do I have?

[briandunning]

You're going to laugh at me for not knowing this, but I also have a beater Jeep for "serious" offroading, so our decision to buy the 4Runner for my wife and weekend trailering was not swayed by what type of 4WD system it has. So I bought it and I don't know.

It's 2006 4x4 V8 Limited. There is a 4Hi/4Lo knob, and also a button on the left that shows a layout of a 4WD drivetrain.

Can someone explain to me in offroader's terms exactly what type of setup I have? Type of axles, type of diffs, what kind of control I have over locking etc.?

Thanks much....

 

[Good Times]

Full Time 4wd (meaning no 2HI just 4LO and 4HI).
Axles - IFS and SA rear
diff - 3.73 gears no front/rear locker. Just a center locker that can be locked and the vsc will be diabled. By default traction control is always enabled (no way to disable unless someone figured it out).

Other features:
DAC (Downhill Accent Control - basically worthless if you offroad any... way too fast for most stuff, unless you like boldering at 5mph)
HAC (Hill Accent Control - helps keep the 4runner in a stationary position when you're either on an uphill or downhill position. Only momentary - good for red lights - infamous two foot action is not needed anymore as vehicle will not roll back.) Some complain about this system as it's doesn't always work apparently.

That's about it. Since you're an offroader, all ya gotta know is it's Full Time 4wd (4hi/4lo) and has no lockers (only center). ARB has a rear locker available RD23 and the front is on it's way (RD111 or RD121 - depending on gears you run).

Good luck!

 

[Good Times]

Another thing to note...

The traction control works wonders. It is computer controlled and will in effect work as if you have a front/rear locker. You can't take it places where a true locked vehicle goes but it can go pretty darn far even w/ a few tires up in the air. Take it out for a spin and check it out. The traction system is much improved and two thumbs up

 

[Thai]

Another thing to note...

The traction control works wonders. It is computer controlled and will in effect work as if you have a front/rear locker. You can't take it places where a true locked vehicle goes but it can go pretty darn far even w/ a few tires up in the air. Take it out for a spin and check it out. The traction system is much improved and two thumbs up

I like to think that ATRAC is equal to other limited-slip differentials, like Torsen LSD or even Jeep QuadraDrive. So, it is really pretty darn good...it's like having LSD's on your front and rear axles all the time! The center diff is lockable.

Cool piece of technology IMO....

 

[briandunning]

I guess my question was a little more specific: I know it's a solid rear axle, but which one, what kind, how strong?

 

[Thai]

I guess my question was a little more specific: I know it's a solid rear axle, but which one, what kind, how strong?

Wow, it took you a whole year to respond!!

The axle is a Toyota 8" ring gear axle, common on Toyota 4runners, FJ Cruiser, GX470/Prado, Tacoma, and previous pickups. I have read that the axle tubes are welded to the diff housing and reinforced. It is a good axle, probably around the Dana 44 strength, maybe a bit stronger.

Unfortunately, nothing in life is perfect. There have been some horror stories of Tacoma owners with rear locker breaking their rear axle (even with stock tires)...stripping the gears or something. And there are a few stories about FJ doing the same thing due to same axle and locker design as Tacoma.

Most Tacoma/FJ owners believe that the Toyota 8" rear axle was excellent in the previous generation where engine power and curb weight were modest. However, due to recent pumping up of power (bigger & more powerful 4.0L V6 engine) and heavier curb weight, the Toyota 8" rear axle does have it's limits. The overseas Prado with rear locker also has stories of blown rear axle due to stress.

Here is a good summary thread on this topic: Factory Locked Rear Differential- problems&solutions - IH8MUD.com Toyota Forum

How does the axle do on 4runners?? Well, i have personally heard of just one instance of someone breaking their rear axle. It is not common in 4runners and GX470. Why? Well, 4runners and GX470 do not come with rear locker, which puts more stress on the gearing teeth of the axle. Goodtimes on this forum have put on big tires (35" or more i think) and his axle is holding up well. But, then again, he does have ARB locker, which seems to help strengthened the axle.

So, if i had a 4runner, then i would not go out and run big tires (anything above 33"), which is a good idea anyway since there is no gears available to re-gear for the big tires. And if i wanted to run bigger tires, then i would get ARB locker. If i had a FJ or Tacoma, then i would NOT get the rear locker option...instead, i would buy ARB's unit.