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Hi Fellas... I'd like to know how to operate properly the AWD system on my 4.4.

This question resulted to my frustration when i climbed a 2 ft probably between 30 to 40 degress angle of of inclned approach to a parking space covered with snow.

first thing i did was to press the lock button on the left hand side of my steering wheel. (correct me if i'm wrong) lock differential button. i waited for the indicator to stay lit. then i began to roll towards the incline with easy and slow approach.

with front wheel first reaching the incline, i gradually step on the accelerator and from wheels conquered the incline with little effort.

then i gently brought in my rear wheels toward the incline. stopped a bit on approached and step on the accelerator. (then the frustration started)

giving the acceleration enough press only made the front wheel spin and rear wheel stayed put. checked on differential lock found it is still on and the indicator on the dash is still lit. tried climbing up and still the same (front wheel spinning a lot while rear wheels are idle. did 5 unsuccessful attempts with same results. and to add salt into the wound, the snow was packed and approach would be slippery and not what you experience with unpacked snow.

so just to overcome the challenged be able to park my rav4, backed up about half the length of my car, step on the gas with a bit of aggression and zoom. got up and parked my rav.

this experience brought a question in my mind. does toyota dealership have a comprehensive way testing AWD/4WD drive systems on their models that can guarantee its working and not just by giving a greed light with their obd2 computer readers.
 

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Under normal circumstances, 100% of the power is being delivered to the front axle, unless the AWD system diverts some of that power to the rear (up to 50%).

The center differential lock couples the front and rear axles together, putting 50% of the power at each axle. However, both the front and rear differentials are open, so the left and right wheels can still rotate at different speeds because it's not true 4X4. So if you lose traction at one wheel, you're sending 50% to the free-spinning wheel, but you still have 50% of power going to the rear axle to hopefully get the front axle past the point of low traction.

Did you have traction control off? If you didn't, you may have been experiencing the power being cut from both axles as your front wheel lost traction. But depending on the grade, 50% power may not have been enough to move the vehicle further. Try not to lose momentum in snow, especially when going uphill.
 

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I'm curious. Is the AWD always on for when you accelerate from a full stop, for the regular gas RAV4s? On the RAV4 Hybrid it is. It shuts off once you get going, but when you start moving from a full stop, the screen always indicates AWD is active. This is even true in warm weather on a dry road.
 

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I'm curious. Is the AWD always on for when you accelerate from a full stop, for the regular gas RAV4s? On the RAV4 Hybrid it is. It shuts off once you get going, but when you start moving from a full stop, the screen always indicates AWD is active. This is even true in warm weather on a dry road.
On my '06 4WD I've installed a green LED on the drive circuit to the rear electro-coupler so I can tell when the rear drive is being activated. (I do have to kinda judge how much the transfer is by the LED's brightness.) I believe the 4.4 non-hybrids use the same system.
While idling in neutral it's off but ASA I shift into any gear it comes on bright. The car hasn't moved yet so the surface has no initial effect. On startoff it stays on until the car gets moving, longer with more throttle but probably completely off by 30 mph or less on dry pavement.
Driving on a snow covered road at 40-50 mph it remains on with any throttle, brighter with a heavier foot, and off with any throttle release.
Couple of interesting observations:
While driving at 60-70 on a dry interstate the LED comes on at least faintly for a couple seconds every minute or so and them goes off abruptly. Can't explain that one. :confused:

Then the other day I was showing a friend how well I could accelerate even on a snowy driveway while he was watching the LED. I floored the V6 producing enough acceleration to cause some sideways sliding and beeping from the VSC system. I hadn't yet backed off but he said the LED went off. Made sense since the VSC was reducing power until I did.

That's what concerns me about the advice to turn off Traction Control when traction is what you need. Isn't it Stability Control that reduces power? Traction control brakes a spinning wheel to aid traction. On my '06 I can't turn them off separately, having to "tap dance" them both off, but my understanding is you can on later models. TRAC on and VSC off would seem best to me.
 

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Don't misunderstand my post. Usually you want traction control ON to help you from losing control of your vehicle, especially on slippery terrain.

The OP was describing a "stuck" scenario. That's why the first sentence in my first reply ended with "that situation."

Turning trac cont off is only advisable in low speed, "stuck" scenarios.

Thanks and drive safe.
 
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