Correct, the open differentials couldn't care less what ratio the transfer case has.

 

You have a point there. My monthly checks also include locking the center-differential too to make sure it functions correctly so I have a spot off-pavement to test those systems at the same time.

 

Now that I think about it, this reminds me of when I test drove a 2004 Lexus LX470 about 8 months ago. It had 45,000 miles on it. When I checked 4Low and the Center-Diff Lock, neither worked. Driven on 4HI all it's life and probably never been shifted to 4LO and never had its center diff-locked. Low mileage for a nearly 10 year old car, but that actuator was probably super-seized.

Edit: Here is the very thread on that same vehicle that I posted awhile back in the LX470 section. It was actually a 2005 with 46,000 miles. This was before I found out about the 4LO issue with my 4Runner.

https://www.clublexus.com/forums/lx4...-difflock.html

 

I must admit I only used 4LO once and probably need to get up to speed with the program. Last year I parked the car after a car wash and it frozen to the ground enough to make me uncomfortable keep gunning it in 4HI to get moving. So I switched to 4LO gave it a little bit of gas and it was enough to get the car moving.

 

I always lock the center diff in the snow, these cars drive like they are on rails with snow tires and center diff locked. This thread reminds me to use 4Lo more for sure.

 

Now this is very interesting topic. On one hand locking the center for sure provides benefits. On the other hand the center diff in the GX is torsen and it does a very good job in distributing the torque and dealing with uneven wheel traction already and locked differential disables it. I guess in a heavy snow conditions locked diff is the way to go for sure.

 

For an area that almost never sees snow, an Atlanta commuter with an FJ Cruiser was able to get home through "Snowpocalypse" with the help of 4-Low. It took him nearly 10 hours, but he never had to abandon his vehicle like many others did:

http://www.fjcruiserforums.com/forum...nk-you-fj.html

 

I abandoned only due to I thought I would get home faster being only 4 miles away from home which could be several hours to drive and I feared getting hit by others. Also 4-low or 4-high do no good when going down hill on ice and I did see some left behind pile ups on the down hill the next day, otherwise I felt stable in my GX.

 

Shifting into 4-low would have enabled you to select your Downhill Assist Control feature and aid you going down the other side. It assists the GX's engine braking in 4 LO further as well as its regular brakes automatically until you want to take control.

I know it might not have been the time to test the feature, but whenever you get a chance, test it out on a slippery surface.

 

Here is more info on the Downhill Assist Control feature. It can only be activated in 4 Low. It's on GX's without the super awesome CRAWL Control:

http://www.toyota-global.com/innovat...e/dac_hac.html

 

[QUOTE=FrigginFGO;8356321]Shifting into 4-low would have enabled you to select your Downhill Assist Control feature and aid you going down the other side. It assists the GX's engine braking in 4 LO further as well as its regular brakes automatically until you want to take control.

I admit I am ignorant to what exactly my truck is capable of. I have turned on DAC before and I think I received beeping so are you saying that if I go 4-low and turn on DAC that the truck will make the best down hill decisions unless I brake or accelerate and this is only active on 4-low?

Edit: Sorry I just noticed your last post. But if you have more clarity I would appreciate it.

 

[QUOTE=tecman;8356377]You are correct. I found a better explanation of the system from a Tundra forum:

http://www.toyotatundraforum.com/tra...-dac-hill.html

"The DAC system assists engine braking to improve directional control during descent on steep or slippery surfaces. When in 4WD low range and with DAC activated, if any one wheel accelerates beyond or below a two-to-four MPH low-speed setting, the DAC system will control the brakes to help ensure the vehicle continues in a straight position when going down a hill. The DAC system is automatically de-activated if the driver depresses the brake pedal, accelerator pedal, or the DAC button.

The active wheel speed sensors enable the operation of the DAC system by determining current road conditions. The system designed to determine current driver operation through an accelerator pedal angle sensor, master cylinder pressure sensor, and the setting of the L4 position switch. DAC next determines its target vehicle speed of two-to-four MPH based on road surface and vehicle driving conditions. When the vehicle accelerates during descent, allowing the vehicle speed to exceed the predetermined speed, DAC is activated. The DAC system will calculate the required brake hydraulic pressure for each wheel, allowing each individual wheel to meet the target vehicle speed."

 

Wow.. impressive, thanks for the info and now I will have confidence going down hill if everyone else will stay out of my way.

 

Anytime Practice it a few times to get a feel for it on a slippery sloped surface.

 

last wednesday very scary ride home.

going down a hill there was a little stream in road. unfortunately had to turn around at bottom as tree was down.

the gx starting slipping around when i tried turning around and then sliding down the hill at one point.

i get out and i almost get swept away. Solid Ice with cold water flowing over it! i was getting worried at that point. The gx kept slipping and going backwards.
i put it in 4Lo, then finally i am able to go uphill. i just revved it and flew up hill with solid ice on road.
4LO saved the day. i didnt lock the differential.