Auto LSD in 4wd?

I have a 2009 Tacoma TRD Sport. I just moved out to Colorado and have recently been doing some trail riding to fly fish the more remote streams. Several times I have been hung up on rocks in 4lo where the tires on opposite corners of the truck have been spinning and no power was sent to the tires with grip. I know this is due to the open differentials on the truck where power is taking the path of least resistance. This is frustrating because I am used to getting through deep mud with no problem with a good bit of throttle.

My question is if auto lsd works in 2wd to use the brakes to distribute power to both wheels, why is it not an option in 4wd and 4lo where it would be more useful? I have read several threads about the "yellow wire mod" but this seems to deal more with ATRAC than ALSD. I'm also not sure if this is a possible mod for Tacomas older than 2012. If there is a way to get ALSD in 4wd, I'd love to know.
Thanks

Here's my baby

 

I thought TRD Sports came with conventional old type design rear LSD's that are mechanical or use clutches, with the front still being open diff and engaged via transfer case when in 4wd

 

There isn't traction control or auto lsd in 4low. You should have it in 4hi though.

 

They stopped using the mechanical LSD in the sport and switched to the brake controlled style at some point but I don't recall what year. 4high should have traction control and auto LSD, 4low turns all traction aids off.

 

I think the 05-08 Tacomas used a clutch type LSD, and they switched to the "electronic LSD" using wheel braking in 2009.

 

Press in the parking brake slightly. This will stop the wheel from spinning and send power to the other wheel on the real axle. It is basically manually doing what traction control does automatically.

 

Research the yellow wire mod. Essentially tricks the 4wd ecu into thinking it's in 4hi when it's actually in 4lo to give you traction aids

 

Paging @David K

beetlejuice .... beetlejuice .... beetlejuice

 

On your 2009 TRD Sport when you are in 4WD Hi you automatically have limited slip both front and rear. In 4WD Lo you have open axles, no limited slip. (There is a mod you can do to get LS in 4Lo ) The thing is when you are in 4WD Hi you can’t get better traction unless you have lockers front and rear. It is rare that you actually need 4L in your truck. The truck has plenty of power, you can power up and over most everything in 4WDH with your automatic LSD. I have a 2009 Sport like yours and spend a lot of time in the back country fishing and hunting and I never need 4Lo, I always get where I’m going in 4Hi with the automatic LSD. Some of the roads and trails I drive on are quite challenging. Next time you head out keep it in 4WD Hi, you’ll be just fine. (I learned this information from the master David K)

 

Yes my friend... I hear you!

 

Hi and don't get mad and shoot the messenger but...

You should have gotten the Off Road TRD!

Since you did not, then the only enhanced traction control is in H2 (Auto LSD) and H4 (TRAC).

2009 to 2011 or 2012 there is no button to push in H4, you are automatically in TRAC without engine regulation (same action as AUTO LSD in H2).

In 2012, they added a button push to achieve the stronger TRAC but now called it 'TRAC OFF' (LOL, I know, crazy terminology). AUTO LSD = TRAC OFF on 2012 and newer.

2009-2011 = TRAC in H4 is limited slip with no regulation of engine output.
2012+ TRAC = Limited slip with engine regulation, TRAC OFF = Limited slip with regulation turned OFF.

You will have better luck in the situation you describe in H4 than L4, which has no traction assist at all in the SPORT TRD. The Yellow Wire or 4 LO TRAC MOD is the solution to get traction control in L4 for the non Off Road Tacomas.

 

This was only from 2005 to 2008.

 

2009

 

You are so kind!!! But, I am just a humble fan of learning puzzling details like these!

 

Thank for you input. I always thought traction control detected slipping and cut power to maintain vehicle control (at least in 2wd) and didn't help power distribution offroad. Are you saying that TRAC acts like AUTO LSD in H4 to distribute power better on uneven terrain? Also I've always turned TRAC off in H4 whenever I get into the mud down south and just kept her pinned. Haven't tried leaving it on when crawling out here, but I'll definitely give it a shot.

 

Thanks for your expertise!

So does that mean 2012+ has limited slip in 4-LOW?

 

No. The TRD offroad has ATRAC but the other trim lines don't have any traction aids in 4L.

 

Your 2012 + has a button push for 'Trac Off' for stronger limited slip (engine regulation turned off). 2009-2011 are in the stronger mode without pressing the button... They just didn't call it a different name than "Trac in H4" but it was similar to AUTO LSD (the 2WD mode with no regulation).

VSC OFF turns it all off if you want the tires to spin to clean out mud or snow from the tires.

 

Edited my post above... damn auto correct on my phone was changing words I wanted to use! LOL

 

I'm looking into reaction aid for a 2020 SR.

Looks like the yellow wire mod could be something that works for this truck.