Please explain Rear Wheel Drive

[mongo]

It might not be that you got hung up in 6" of snow with a RWD car, it might be that you got hung up in 6" of snow in a RWD car with Dunlop performance tires.

My wife's FWD minivan is a rock star in the snow compared to the Genesis with the Dunlops.

Same with my son's 20-year old RWD Volvo 240, or my RWD Jag XJ8.

While I agree a FWD could handle better in snow than a RWD, it's not just RWD vs FWD. The Dunlops come into play as well. I grew up driving on snow and ice on RWD, and these Dunlops are like driving with slicks.

 

[wallymn]

I was in NJ this week on vacation. They had snow. Family/friends rides were a mix of front and awd. None had winter tires.

My Genesis held the road much better than STi AWD with All season BFG, and an Acura TSX (I didn't catch the tire brand).

Both cars could be better in snow. The STi could kill the G if winter tires were installed, but with all seasons, it pushed and slid where I wasn't losing traction.

 

[scottdk]

I was in NJ this week on vacation. They had snow. Family/friends rides were a mix of front and awd. None had winter tires.

My Genesis held the road much better than STi AWD with All season BFG, and an Acura TSX (I didn't catch the tire brand).

Both cars could be better in snow. The STi could kill the G if winter tires were installed, but with all seasons, it pushed and slid where I wasn't losing traction.

I agree completely Wally. Also, an STi form the factory has BFG's that are SUMMER only tires. Also noticable by the crazy looking tread.

 

[Disaster]

Here is another example of the difference between AWD vs. RWD and All-seasons vs. winter tires.

This afternoon I had to drive my son back to college. As luck would have it, snow was predicted (just like our trip back last year.) We drove our AWD Volvo XC70 with Continental 4x4 Contacts (with 20K miles on them.) By the time we got into the college, the snow was coming down and there was maybe a half inch to inch on the ground...with no grooming. My son was driving and he kept overshooting traffic stops...as the anti-lock brakes went into overdrive. It snowed the entire time back and the car felt like it was floating around....slow acceleration...looooonnnng braking distances...but the even distribution of power and the electronic stability control kept the car pointed straight. I stayed on the road, but never felt "safe." The car was a sled. Leaving a traffic light, left turn, from the freeway, I tried to beat the line of traffic by taking the outside lane (I was tired from 5 hours of driving and just wanted to get home.) The Volvo just slid wayyyy wide and I had to countersteer it back...there was just no traction to speak of.

Meanwhile, my wife drove the Genesis, with fresh Michelin X-Ice's. She drove the same last part of the trip home (from work) that I did, just 30 minutes behind me (with the snow continuing to fall.) She said the tires slipped a little accelerating out of the parking lot but she didn't think the roads were that bad. She couldn't understand why I had such a hard time.

When she got home I took the Genny out for a spin around the block and the difference was amazing. Where the Volvo would slide 20 feet...the ABS screaming...the Genny would just give a couple clicks of ABS and uneventfully stop...in half the distance. I could push the tail out on the Genny but it was no worse than the Volvo...and I was able to get it's composure back much faster.

Tires being equal, I'm sure the Volvo would do better. But, the Genny with it's winter tires, was far superior to the Volvo and it's all seasons...the same kind of all seasons...with similar amount of wear...that 90% of the drivers are on the road with.

Bottom line, if you really want to be safe in winter driving worry less about whether you have AWD, FWD or RWD and more about what tires are on your car.

 

[mikec]

Decades ago, when almost all cars were RWD, car manufacturers didn't care/know much about front-to-rear weight distribution. Cars tended to be quite nose-heavy. When cars went from body on frame design (i.e. heavy) to unibody (lighter to save fuel and meet government mandated CAFE MPG requirements) smaller engines were "adequate." Smaller engines fit transversely (sideways) under the hood allowing FWD. Manufaturers liked FWD because it was cheaper to produce: the engine+tranny+differential+lots of suspension stuff could be assembled as a package and then installed (from underneath) into the vehicle body with fewer assembly line workers. Manufacturers touted the "we put the drive wheels where the weight was" as if that's why they switched to FWD... not mentioning it was cheaper for them to manufacture.

Meanwhile, tire technology (both tread and rubber/material tech) has grown by leaps and bounds in the last couple decades. Thus All-Season tires work almost as well as pure snow tires of 30+ years ago. Today's snow tires though gained just as much and work better yet. Today, computer simulation of tread and rubber compounds allows tire companies to test/develop far faster/more cheaply than decades ago when prototype designs/ideas had to be hand-built and then manually tested.

When FWD first became common, folks were comparing the snow traction of FWD to those old RWD vehicles with lousy weight distribution... no wonder FWD got such a good reputation. A properly balanced car (FWD or RWD) will do better overall (across lots of driving/weather conditions) though. Nose-heavy FWD might be great for accelerating in snow but it is worse than a 50-50 balanced FWD or RWD vehicle in other (e.g. some emergency) maneuvers. There is no "best at everything" combo unfortunately. 50-50 weight distribution is generally the best overall "one size fits all" combo.

No matter what, the vehicle's capability is dictated by the tire contact points with the ground. FWD or RWD, weight distribution, etc. just determine how much of the total available tire traction capability will be used. That's why real snow tires will generally out-perform all-seasons in snow: they're starting with more capability. For 99% of the time though the all-seasons may have "enough" traction/grip/performance to handle the weather. That last 1% of the time though - which might be emergency conditions - is when snow tires may make a difference. Remember too most car buyers/owners are concerned with "not getting stuck" in snow/ice conditions... so, if their current vehicle (FWD or RWD, whatever, with all-season tires) hasn't gotten stuck they're satisfied. Few folks consider stopping performance - "not getting stuck" is the dominant consideration for the general population. Have they actually tried real snow tires? Probably not - "why should I spend that money when my existing all-seasons work well enough - I've never gotten stuck." Perhaps they've never been in that 1% situation... just like wearing seat belts. "I didn't wear them for an entire year and I didn't die... so why should I ever wear them?" 99.9% of the time you don't need them... but when you DO need them, they can make a big difference.

Driving enthusiasts, more experienced drivers, and folks that have survived those 1% events tend to think of "stopping" and "steering" in addition to "not getting stuck." Most of those folks will get the snow tires, or will recognize the lower limits of all-seasons by not driving on snow covered roads whenever possible. When they try to convice "the rest of the population" of the snow tire advantages, they often get ridiculed as being paranoid and what-not. Until the average schmo gets that 1% scare...

mike c.

 

[Disaster]

Driving enthusiasts, more experienced drivers, and folks that have survived those 1% events tend to think of "stopping" and "steering" in addition to "not getting stuck." Most of those folks will get the snow tires, or will recognize the lower limits of all-seasons by not driving on snow covered roads whenever possible. When they try to convice "the rest of the population" of the snow tire advantages, they often get ridiculed as being paranoid and what-not. Until the average schmo gets that 1% scare...

Excellently written. I agree with the seat belt analogy.

Another thing that I am sure contributes to people not getting snow tires, are leases. It is even harder to justify getting an extra set of tires when you will be turning the car in before they are even worn out.

I must admit, that is why we have the crappy all seasons on the Volvo. It is a 2 year lease. We bought the Genny to replace it and the first thing I did was order a set of winter snows for it.