I heard it's a rear wheel drive biased drive and the all wheel kicks in when it detects slippage. What % is the split and how exactly does it work?

 

My understanding is that it's 70% rear, 30% front by default. It can shift up to 50% to the front if it detects slip. I need to find a source for that, but I remember reading it somewhere. From a quick Google search I found this info on the 2IS: https://pressroom.lexus.com/lexus-is...wd-rwd-models/

I am almost certain it's the same for the 3IS.

 

Everything you want to know is in this thread here....

https://www.clublexus.com/forums/is-...stem-tech.html

the awd is very RWD bias. I drive everyday with trac fully disabled. When it’s wet I kick it out around corners, and sweeping turns, on/off ramps, when safe to do so... I drive the **** out of my car. It’s really fun until the front wheels kick in and start pulling while the rear push. Weird sensation at first.

this is me in the snow last year. Good example of how rear bias it is. Again, full trac disable, traction is insanely intrusive in this car.

 

Thanks, it's snowing in Jersey like crazy, I had snow mode on.. car was doing really well (even on very low tread Michelin A/S 3+ tires in the rear). What does snow mode do?

@ALLBLCK604 damn whipping it in that video

 

 

I’m not too sure what snow mode does I’ve read it starts you in second gear, but I tried it and it’s not true. I would assume it dulls the throttle, shifts sooner, it’s all electronic bs.

haha yeah man I love kicking the **** out of my car lol. I had blizzaks on in that video, they’re awesome. I only ever drive in the snow (all year round for that matter) in M, S+ with traction fully disabled. My traction control is my right foot. Can’t wait til it snows again, more footage to come haha

 

Part of what it does is reduce the acceleration so it feels like you are driving a corolla, it's intended to reduce slippage on snow/ice. On my old RWD 2IS it helped when the snow was heavy.
I thought only RWD had it but the AWD models do as well, it's needed more on RWD though at least in my experience as I have never needed it on my AWD 3IS which is why I forgot it even existed.

 

I noticed it wouldn't go past the 5th gear either, was going up a slope at about 30-35 degrees and it shifted down to 3rd gear.. and yeah, stayed in very low RPM

 

Don't bother with snow mode i had RWD and AWD ISXXX. Both get snow tire which really helps and depending on how deep the snow both turn off traction fully/ VSC so power don't cut down.

 

Snow Mode does not start in second gear, or at least, I never observed it doing that. From what I can tell it changes the way the throttle responds, similarly to Eco Mode. However, I think it must change the AWD strategy somewhat as well. When I had ESC and TC fully off, I think the car drifted a bit less with Snow Mode. I am not sure whether the driving dynamics difference was due to the AWD system or simply smoother throttle application.

So I would say overall it doesn't make a huge difference, but I would say it might be a good idea to turn on Snow Mode if you are legit driving in snow as opposed to on slush, provided you want to be safe and not a hooligan.

 

You can google it there’s some detailed articles on the the system.

like Arentz said it’s full time AWD with a 70-30 rear power split until slippage is detected then it can split power 50/50 front rear... first thing I do when I drive it, EVERY time is disable TRAC it’s sooo intrusive and if you are even a half capable driver you’ll be better with it off.

We don’t have any LSD in the car or anything like that, no torque vectoring etc...
it’s no where near as good as Subaru’s, Acura’s, Mercedes, Audi’s AWD systems BUT I’m in a part of Canada that gets absurd blizzards and snow 5 months of the year..like so bad the city literally shuts down, and ive been able to drive through anything.
Ground clearance becomes an issue, not traction with the AWD models. Also you can pull off some awesome power slides/drifts in the winter with the AWD and traction fully off.
I know Toyota use to have a crazy AWD system they developed from their rally days called ATTS, not sure why they couldn’t incorporate a better system to rival the competition. Either way it works incredibly well and I’ve made it through Canadian mountains during blizzards no prob while other cars are pulled off to the side or to scared to even leave.

Here is a pic of a typical winter morning where I am. My 350 AWD gets through it like nothing.

 

snow mode simply dumbs down throttle response by a lot even when compared to ECO. Just makes it easier to not break grip on rear tires when driving on ice and snow.

 

yep.. I drive RWD is350 and disabling TRAC and stability control is a must when driving in snow. It is also fun and a nice slow (reaction time wise) practice which clear concrete or asphalt road surfaces usually do not allow for. Too bad, we got no snow in KS =(

 

The only time when SNOW mode helps, is when you are in a rear wheel drive version and are trying to climb up a hill. Then in normal or eco mode it is very easy to break grip. Snow mode simply allows to be more precise with how much torque you are applying.