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'07 Toyota RAV4

The electronic 4-wheel drive kicks out at road speed and is unavailable in highway situations. Is there any way to force it to stay on? Say a highway covered with slush snow at a speed of 40 mph, or higher.

The AWD system on the RAV is an “on demand” system, meaning that it normally runs as a FWD vehicle and it sends power to the rear wheels when it detects slippage of the front wheels. As soon as traction to the front wheels in normalized, it returns automatically to FWD mode.

There is an override switch to send power to all 4 wheels, but it can only be used up to…25 mph…if I recall correctly. You can verify what I have said by reading the Owner’s Manual, and it might be a good idea for you to read through the section of the manual dealing with the AWD system for all of the pertinent details.

Unfortunately, if you wanted a vehicle with permanent AWD, this was not the vehicle to buy. “Forcing” the system to do what it was not designed to do is a sure formula for mechanical failure. Sorry.

I don’t think you want it on at road speed. 4WD is great to get you out of the ditch or to keep you going in deep snow, but it has limited if any advantage at keeping you on the road or helping you stop.

The right tool for the job at highway speeds (you certainly should not be driving at highway speeds under the conditions that 4WD really helps) is a set of four winter tyres.

It’s the locking feature that kicks out…The awd system will be engaged ALL of the time, it has a front drive bias and will auto matically shift more power front to back as needed,detected by slippage or other electronic means.

For example, even above 40 mph, if you start to climb a hill the bias will shift to the rear so that you can retain steering control and momentum going up a hill…It’s the locking feature that disengages at higher speed. The locking feature locks in a constant 55%/45% front and rear WHICH IS BETTER FOR slower off road. My RAV, an 05 is different, because it does not have the locking feature but is still always in awd.

Have you checked your manual to see what the indicator lights actually mean ? You should NOT normally engage the locking feature unless in deep snow or mud. If it disengages the traction control with lock in that’s great…that will save your rear brakes when slogging slowly through deep snow and mud, like in a4Runner.

Again…read the manual, it may seem complicated. but you want to know how it works.

Sorry to disagree…but you do want awd engaged all time and at all speeds in slippery conditions…you confuse awd with truck based 4 wd which when locked in at high speeds can cause steering control issues when cornering. People that don’t own or drive BOTH systems in winter conditions can be easily confused by each’s limitations and advantages. Even review periodicals confuse awd with truck based limited 4wd nomanclature. To further confuse the issue, many modern vehicles are capable of both systems. Like the RAV4 in this thread.

Winter tires I feel, are more important on awd because of the excessive speeds they are capable and you don’t want to out drive the system capabilies which are ALWAYS greater than a 2wd.