"As a matter of fact, an all season tread will give you much better traction on glare ice than a snow tire "
False. Modern winter tires have studless design with special tread made to grip onto ice better than an all-season tires. All-seasons are compromised in tread compound/design so they can work in the cold and warm temps. This greater traction on ice and snow makes the need for having four when you need to stop and for lateral stability(avoiding spinning).
Your comments apply though to the old school design winter tires call snow tires that were cruddy on most surfaces but deep snow. People sometimes added studs to make up for the poor ice traction with them however wet and dry traction left a lot to be desired.
Due to a switchback where gaining momentum was impossible to get up a hill and the shared uphill untreated except for plow and sun to remove snow pack/ice.
Living in the Mountain region of NH 4x4 may be required…But MOST of the NH population is Concord and south…where a 4x4 is NOT needed. In fact you can easily get around with decent All-season tires. My wife has NEVER put snows on her vehicle since we moved to NH 20+ years ago. Her Accords and now Lexus get around GREAT with just decent all-season tires.
When it comes to snow I don’t believe winter tires do a whole lot more then all seasons. It’s in the freezing rain and drizzle that they make the difference.
The all seasons I had on my van were completely useless on ice (it slid down my driveway one year after I parked - even though the grade was only slight).
When I got the winter tires I couldn’t believe I had been so stubborn for so long - the difference in the winter tire’s ability to grip on the slippery surfaces was amazing. I’ll never go without winter tires again.
It is more than that. With RWD, converting the longitudinal torque to lateral torque requires a rear differential that uses gears to change the direction of axis. That use of gears leads to a reduction of power.
Look at it this way. There are two motorcycles, both with the same engine and the same size wheels. Both engines rotate on a lateral axis and both rear wheels rotate on a lateral axis. One is chain or belt-driven and one is shaft-driven. The chain driven motorcycle will be more efficient and there will almost no power loss compared to the motorcycle that is shaft driven becuse the torque must be converted from lateral to longitudinal, and back to lateral again. As the gears convert that axis of rotation, power is lost. The chain driven motorcycle will use less fuel traveling at the same speed. It will also go faster than the shaft-driven motorcycle at the same amount of engine RPMs.
With all other things equal, this is why front wheel drive cars are more efficient. They don’t have to convert the torque of the engine 90 degrees like a RWD car does. That conversion alone leads to a loss of power between the transmission and the drive wheels. It has less to do with weight and perception and more to do with the physics of converting torque using gears.
Naw, I respectfully disagree. The gears in a differential probably lose less than is used up in the operating friction of the CV joints in a FWD car. Chains are, compared to gears, much less efficient. Beyond the inherent higher friction involved in bending and unbending teh links and the inherant higher friction of the not as perfect mating of the chain to the sprocket, they also contuinually convert angular momentum into linear momentum. They have to keep changing the direction of the links, and changing direction of a mass takes energy.
FWD or RWD, the final drive ratios for a given engine vs. drive wheel will have to end up being the same, and that’ll require gears. While I understand your point about RWD probably requireing additional gears, changing direction 90 degrees by the use of a ring & pinion set requires no more energy than that of two helical gears of the same ratio. There is no loss there. There is no change in direction of any mass.
Studs still work better on ice and I was always ready to pay the price of poorer performance on wet and dry pavement. The price is small compared to the gain when I really needed it on ice. Contrary to what some ill informed States highway departments believe, Canadian studies have shown that modern studs do not significanly decrease pavement life.
Front engine, wrong wheel drive vehicles are more efficient for the manufacturer because they are cheaper to build. Rear wheel drive vehicles are better for performance of a multi passenger vehicle. The only thing better for performance is rear wheel drive, mid engine, but that is not practical for a multi passenger vehicle.