bkanic

Hi,

I'm about to purchase a 2010 RX350. I was disapointed to hear that
the 2010 does not come with Full-Time AWD.

Does anyone here have any experience comparing the 2006-2009 vs 2010
AWD systems in the snow?

If safety is my number one priorty for this vehicle,
does the 2006-2009 AWD out perform a 2010?

Thanks

bkanic

I dont believe no one here has upgraded from a 2006-2009RX350 to a 2010 RX350
Does one RX perform better in the snow than the other?

kitlz

Actually a few people have made the switch from 2nd gen to 3rd gen.

The '10 350 is full time AWD, the 450h is 'on-demand' AWD. Both have active torque control. Here is a video demonstration:

http://www.lexus.com/models/RX/featu...ml?demo=rx_awd

I got my 450h in January and the 'part-time' AWD was put into use almost immediately. I was a tad concerned but that quickly went away after a trek up and down a mile long snow covered hill with turns. The plows weren't out yet. I had no problems unlike the SUV in front of me. Didn't even have snow mode on either.

Now I have 19"s on my 450h, 2006-2009 RXs will have 18"s or even 17"s. And the 450h weighs about 700-800 lbs more. But I'd say it performs as well if not better than my 1999 RX300 and 2004 RX330 in the snow. I'm sure the '10 350 will be great too.

bkanic

The '10 350 is full time AWD, the 450h is 'on-demand' AWD. Both have active torque control. Here is a video demonstration:

Hi Antia,

Ya I don't think it's full time all wheel drive. It's Front wheel that turns on the back wheels on and off as needed.
The 2006-2009 is always on AWD.

That's why I wanted to know if there is a noticable performance differance.

hypervish

I believe Anita is right! On the Lexus website for the 350 it says that it has active torque control along with variable torque split. That means the rear wheels always have some power not much, but as the terrain gets worse they get more, and more power. For the 450h it is part-time AWD, essentially only being used when slipping is detected, or when you manually lock the diff.

bkanic

Is there someway to get more clarification?
This is also from the website:
This innovative system can adjust front to rear torque ratio from 50:50 to 100:0 for optimum control and fuel efficiency.
I'm pretty sure 100:0 means 100% front wheel drive

Also, if you set the lock differentcial, and it turns off over 50km/h, does it turn back on when fully stopped again?

MEP7557

The 2010 350RX AWD is not full time AWD. It is on demand/ necessity only. I have the AWD and have yet to feel any steering torque, which is why I got the AWD.

The lock has to be set each time you want to use it. It does not automatically turn back on.

The RX450H I don't know about.

bkanic

[QUOTE=MEP7557;5745719] I have the AWD and have yet to feel any steering torque, which is why I got the AWD.

QUOTE]

Sorry, I don't understand the above. Please clarify
Isn't the 2010 a Front wheel drive? So it's the back the kicks on...

MEP7557

That is correct. Under acceleration some of the torque is sent to the rear wheels, this prevents torque steer which is a common problem with front wheel drive only vehicles. Torque steer is the feeling that the car wants to continue going straight as you are trying to turn. The rear wheels come to life when slippage of the front wheels is detected as well. If you are just cruising along it is front wheel only. This is how they were able to get 1 more mpg out of it.

06i

so neither (350/450) systems are full time?

snomuncher

From a review of sales literature, Lexus web info, and the 2010 RX350 owner's manual, and as stated by others above, the Active Torque Control of the AWD is an "on-demand" feature. Normal driving mode is front wheel drive only (100% torque through the front wheels) but when the ECU/PCU senses slippage or another condition that warrants sending power to the rear wheels, it does so. Engaging the four-wheel lock feature will override the automatic feature of the "on-demand" operation subject to limits (e.g., will not stay engaged above 40 mph).

This is a contrast to earlier RXs like my 2001 RX300 that had full-time AWD, with no options for selection of an alternate mode of operation. That was "AWD, all the time."

Having owned four wheel drive pickups and SUVs for over 30 years, from those with manual lockout hubs to pushbutton selection of four wheel drive modes, I have no reason to be concerned about the safety or capability of my 2010 RX350 in snow. On my four wheel drive Chevy Silverado, I used to run that truck in "on-demand" mode (GM called it "Auto 4WD") all the time in the winter with no issues.

GrandSedanFan

iTrader: (1)

Actually, what you described there is understeer. Torque steer is the feeling that car wants to pull the wheel from your hand under heavy acceleration. The car will dart all over the road when you nail the throttle. The power and grip is never completely even side to side and the front wheels aren't fixed, so the car won't track in a straight line under heavy load.

hypervish

I stand corrected, neither the RX350 or RX450H have "full-time AWD".

kitlz

The information I posted above was from last year's brochure. I also have the window stickers of a '10 350 I test drove a year ago and my 450h. For the 350 it says "Full time active torque control all-wheel drive system." On the 450h, "On-demand all-wheel drive." And each has vehicle stability control (VSC).

Both of these RXs were equipped with the sport package, which includes vehicle dynamic integrated management system (VDIM) that "uses a series of sensors positioned throughout the vehicle to help anticipate and correct for loss of traction before it occurs." (from the brochure) It senses braking surfaces and adds steering torque to either side as needed (also from the brochure). VSC can also be turned off with the sport package. I have yet to figure out how. Not that I think I'll need to. I've been very happy with the way my 450h has performed so far, part time AWD and all.

afpj

I like the newer AWD of the 2010 over our previous 2005. Like others described, it's now an "on demand" system without having to touch any buttons. On demand because of the active torque distribution system. No difference going up a loose dirt/gravel hill (which I travel monthly) between the two cars. Same with my GM truck in AWD mode, but if the GM is put into 2WD (RWD) then there's definitely some slip up that hill. Also, by using this newer system, the smaller spare tire won't stress the gears like it would on a "full time" AWD that has power going to all wheels all the time (granted, at different percentages at different times). Not that you should travel great lengths on the spare, but there's alot of nowhere around here. Sorry to the OP that wanted info on snow, but this may help....