Right on. I only use 4wd when the road is pretty much covered. If there are stretches of bare spots, I just leave it in 2wd.
If the road is covered in snot, I’m staying home. Or maybe taking my wife’s car 
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There’s lots of automotive misinformation in the press. Time filler or space filler.
Better advice is: Vehicles vary. Read your owners manual.
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Another anecdote from me. Driving to work when living in Utah, had I not had my 4WD engaged, I would have not made it to work. 2WD cars and trucks were either at the bottom of the hills or slid off to the side part way up. When back on clear dry pavement shift back to 2WD. Left hubs engaged for much of the winter.
4WD slings no more snow/slush/mud than 2WD unless you are deliberately spinning the wheels.
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Here’s how I learned, safely and first hand, about 4WD drivetrain bindup on pavement, in my 1979 Toyota 4X4 pickup:
On hard dry pavement on a quiet street, lock the front hubs and put the shifts into 4X4 low range, first gear. Drive forward at low speed and try to make a turn. You’ll sense the strain in the drivetrain. Then one or more of the tires will slip forward, relieving some of that binding. It becomes obvious that you don’t want to subject your vehicle to those stresses. Read owners manual and follow its guidance.
AKA as don’t do that.
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You should never drive at highway speed in 4 wheel drive unless you want to destroy your tires or stress your drivetrain when it is dry. In 4 wheel drive in ice and snow conditions, if 4 wheel drive makesyour tires slip against each other on dry road, what do you think happens on ice. There are exceptions, Deeply covered roads may require 4 wheel drive to get through as may steep uphills but you probably should not be going over 40. The varying torque forces cause you to rotate too easily over that.
If you are an experienced rally driver or just like to have fun in the snow like I do, ignore all of that.
All wheel drive is generally ok in slippery conditions although I have seen super slippery conditions, like a road flashes over instantly in freezing rain as the temp drops and the only way to stay on the road is to keep all the wheels rolling with neither acceleration or drag. The best way to accomplish this in a tractor trailer is to quickly throw in the clutch and stay away from the brake. In an automatic transmission vehicle the only way to do this would be to shift into neutral or modulate the gas pedal so there was no engine braking or acceleration. Very difficult to do.
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I have seen a lot of drivers who wanted snow tires or 4WD to go in ice and snow not give any consideration to stopping on ice or snow. I would prefer to have most of them spinning in their driveway vs them closing on me when they cannot stop. I cringe when I see the headlights of the car behind me bob and weave when we are both trying to stop on ice, I know they are out of control then.
Transfer case: The gearbox behind the transmission that sends drive to the front and back on a 4WD or AWD vehicle. Simple ones have a 2WD setting, 4WD setting that locks the front and rear axles together and a 4WD low setting that drops the final drive ratio to about 1/2. In the 4WD setting the driveshafts turn at exactly the same speed causing a bind in the driveline. On dry pavement a BIG bind, on slippy pavement, a minimal bind. On ice when tires spin, TWO tires, one front and one rear (without limited slip differentials)
AWD transfer case: A center differential is added to the transfer case to eliminate the bind so that AWD can be used all the time. On ice, ONE wheel will spin, just one! OR the transfer case has a lockup mechanism that only kicks in the front wheels if the rears slip. On ice TWO wheels spin, one front, one rear.
Locking front hubs: To improve fuel economy in 2WD, the entire connection from the transfer case can be disconnected from the front wheels so the drag from the driveshaft and axle shafts are not included. The locking front hubs UN-LOCK the front driveline so even if the 4WD lever for the transfer case is selected, the front wheels are not driven until the front hubs are locked. Normally in bad conditions, you’d lock the front hubs and drive in 2WD until you need 4WD and then you’d be ready to go. Automatic locking hubs just add an actuator so that when 4WD or AWD is selected, the hubs are locked FOR you.
Center Differential: Because the front and rear tires do not turn at the same speed when going around a corner (just like the inside and outside tires) a center differential is required to prevent binding for full-time 4WD or AWD operation. With 3 differentials (rear, center, front), on slippy surfaces, the ONE wheel with the least traction will spin.
Limited Slip (or locking) Differentials with AWD: If we put a limited slip diff in the rear, one front will likely spin. If we put the limited slip diff in the center, TWO wheels will spin. If we have a limited slip rear and center, THREE wheels will spin! The BEST is three, gear-type (Torsen) limited slips… all 4 wheels will grip and go.
Hope that clears things up.
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Topic drift. Where we is now snot where we started.
Snot the best use of our time.
But snot surprising it went this way.
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"You might be curious, what’s the difference between AWD and FWD in the Toyota RAV4? And which is better for driving through snow? Both systems power all four wheels, but AWD does not require any input from the driver (it automatically engages when needed), whereas 4WD must be activated by the driver. "
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An FWD only powers the front wheels. On a RAV4, FWD is standard, AWD drive is available.
Very informative post. Please just go away.
Heh heh. Ever seen a guy so mad they shake and turn red in the face? That was the picture in my mind with steam coming out. Can’t for the life of me figure out what Scrapyard said that set him off, but it’s an exclusive club that he joined now. I’ll send him a bill for the initiation fee.
Bottom line: on a slippery surface such as icy or wet pavement, 4WD can cause loss of steering control that might not have occurred with 2WD. In 2WD the non-driven wheels will see only sideways forces but not the extra tractive (inline) forces caused by the mismatch of front and rear axle speeds that occur with 4WD when in turns, etc.
It might help to understand this if one visualizes the situation of coasting through a slippery curve with the clutch pedal down - in 2WD drive mode no wheel will see a tractive load and each wheel’s full potential grip is available for the side force demands of steering. As a turn, no matter how slight, is encountered in 4WD the difference of front and rear axle speeds will create inline or tractive forces at the tires (some trying to speed up, others to slow), reducing each tire’s margin of grip available for steering control. The same tractive vs. lateral load trade-off applies when wheels are being driven by the engine (or retarded by braking), a tire will slip then a combination of inline and side loads exceeds the overall friction limit of the tire.
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Oh boy, that brings back memories. There is one stretch of interstate on my way home from work that is a long hill going down, a turn at the bottom, and then going up the hill again after that. On very slippery conditions, with my old RWD there were times that I would put it into neutral so that the rear wheels would not drag enough to cause the rear to try an slide (resulting in down the steep bank at the bottom), then popping it back in gear to try and gingerly make it up the hill again without spinning the wheels. With my FWD it seemed even worse because if the front wheels started to drag, you would surely lose control, so I popped it into neutral also.
I guess you just have to play it by ear and be in tune with the car you are driving. 4WD though would have scared the beejesus out of me though going down the hill. Nice going up maybe. The smarted thing I ever did was to order posi-traction on my Olds which made the difference many times.
All that explanation sounds great, but, I can tell you from experience that 4wd helps you to maintain control on snow in a Jeep CJ 5 and a rear wheel drive truck. I’ve driven several of both of those vehicles on snow in 2wd and 4wd. The rear end wanted to trade places with the front end much easier in 2wd.
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Near the exit from my old school’s campus, there was a somewhat steep grade that cars with FWD and decent tires had no problem negotiating when it snowed. But, I can recall at least three instances of RWD cars getting stuck and sliding into a ditch while I watched.
In every case, the car was a Chevy Monte Carlo driven by a woman, and in every case, she slowed down to a crawl at the base of the hill, and then “gunned” it. Predictably, this was not the way to deal with a hill that was fairly steep, but was less than 1/8 of a mile in length.
In retrospect, I wonder if it was the same Monte Carlo and the same driver each time. 
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