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Comments
The reason that you don't put snow tires on just the front of a fwd vehicle is because when you hit the brakes, the weight transfer to the front of the vehicle will have the fronts biting and the rears sliding... having less traction back there to start with only amplifies the issue, and you can easily end up swapping ends. The same would go for a rwd vehicle really, since you have the same weight transfer during deceleration.
Still, how does it make fwd or fwd-biased awd inherently dangerous? Sure, if you just mount chains or snow tires on the front (who'd do that?), but on its own, I never have believed that.
Any unknowledgeable owner who follows the Toyota HL or Lexus RX owners manual instructions for use of snowchains!
We're halfway there...
You obviously understand why mounting snowchains only on the front can quickly become hazardous on a slippery surface. Absent snowchains the advantage touted by the industry for FWD is higher traction (front engine/weight) to get up and go in adverse weather.
Adding snowchains or snow tire (only front) to the equation exacerbates the effect so dramatically that it is undeniable. Put both a FWD and a RWD, both with expert drivers, on an ice rink and just watch. The RWD vehicle makes full use of the rear tire's contact patch, while on the FWD the rear tires are only there, mostly, to support the weight of the vehicle.
When I lift the throttle on the RWD vehicle the rear tires will provide some (minimal??) braking affect leaving the entire front contact patch for directional control. Do the same in a FWD vehicle and you'll soon be wishing for a clutch, unless you're practised at slipping the transmission into neutral.
Now go a bit farther and add ABS to either vehicle. You'll find ABS useless in both cases.
You can't, shouldn't, always believe the automotive industry, their end goal is to move your money into their pockets.
Precisely. And dead people don't buy cars, and people who believe they are at risk of being seriously injured or killed while driving a particular car won't buy that car. Therefore, it is in the automotive industry's best interests to build safe cars, with safe powertrains and braking systems. If FWD and ABS were inherently unsafe, the auto industry would not use those technologies because over time people would refuse to buy cars that employ them.
I'm planning on buying a XLE AWD with Package HI (leather, dvd, nav). Can someone confirm if that would include the following:
- Side and curtain airbags ? (not mentioned)
- Moonroof ?
While the package description doesn't include these, I can't find any allowed combinations that would. So I'm wondering if they're included but not explicitly mentioned.
Also, can someone who has the Navigation system answer these questions?
1. Can the nav screen play the DVD playing on the DVD player ? Does the car have to be parked ?
2. What does the Nav system prevent you from doing when the vehicle is moving ? entering addresses ? or any interaction whatsoever ? Is this based on speed, or do you have to be in Park ?
3. Does the Nav support voice response, and/or voice activation ?
And I didn't say ABS was unsafe I was simply pointing out that in some circumstances it is detrimental.
Oh, and by the way....
DEAD PEOPLE DON'T BUY CIGARETTES!
Remember ??
In 57 Ford sold safety and GM sold cars.....
Okay, let's leave out the rocket scientists who would be foolish enough to put chains on the front. I've never used chains except when driving a semi-truck. If you're going to live where there's snow and ice, buy snow tires.
I owned a 4wd MPV van for a number of years. This was a rwd vehicle with push-button 4wd. In the winter I always had snow tires on it, on all four, so that traction was predictable. I could easily be in 2wd and hit a slick spot on the road and get the van sideways until I put the van into 4wd, and in that mode, it was very predictable. Not my idea of safe, getting sideways on the parkway at 45mph. Plus, if I got into a corner too hot, the rwd wouldn't help any more than fwd, b/c most every car is designed to understeer at its limits, so... it would understeer still. Putting it into 4wd would allow the front wheels to both steer and power it.
Now, w/a fwd vehicle, I've never, in going on 20yrs of winter driving lost control on the ice or snow, except if I'm exceeding the road's limits. I've also driven fwd-biased awd vehicles a great deal, and never had a loss of control issue. Funny tho, my rwd vehicle could lose control easily, unless it was in 4wd mode.
So, I still don't buy the fwd and fwd-biased awd system is dangerous thought, although I definitely can say that it would be foolish to drive around with chains on the front of the car. To me that's a given.
java... looking foward to his 'dangerous' awd Sienna.
Steve, Host
So....
When else would you expect to lose control as pertains to these discussions........??
Interesting news at:
http://www.nytimes.com/2003/10/06/automobiles/06cars.html
I'm not real sure I'm going to like it when computers start over-riding my steering inputs...
Still, west, how is rwd going to help if I exceed the adhesion limits of the roadbed, anymore than fwd or awd? I can actually see some advantages, though. Let's say that I approach a stoplight, and hit a patch of ice. In a rwd car, it would be easier to gear down and use the rear tires to brake the car. I know you mentioned this. This tactic is also very effective on a fwd car, assuming again that you didn't lash chains to just the front end.
However, a fwd or awd Sienna isn't going to go all crazy and crash if you hit the brakes on ice, I'm very certain, even if you're going too fast. It's going to stop in a straight line, aided by ABS and it's multiple other stability systems. Again, this assuming some idgit didn't put tire chains on just the front. I'm still astounded that someone would do something like that.
Another situation, you are in a turn, and notice that you came in too hot. It happens. How is the fwd/awd Sienna going to be dangerous here? A rwd vehicle is still going to understeer, b/c you've lost grip to the fronts, the way I see it. Rwd is going to push you straight because your fronts cannot give you any directional control. If you have awd, at least the fronts can give some sort of directional motation. If you're going slow enough, I can see how rwd would give you throttle on oversteer, which is always fun. Are we putting chains on the back of the hypothetical rwd vehicle though? How many people actually use tire chains anymore? I would think that most people actually spend the money on snow tires, no?
What am I missing in the big conspiracy?
A FWD with snows is much safer than a rear wheel drive, or AWD without snows.
The traction problems caused by only having chains/snows on the front would be the same if it was done to a rear wheel drive vehicle. (these can be severe - I tried snows on the front only and it is an easy way to go backwards down the street)
Obviously you are not using your drive wheels while braking, and you shouldn't be while turning on slippery surfaces.
HI (Package # 21) has the following:
-Leather Trimmed Seats
-2nd & 3rd Row Side Sunshades
-AM/FM/CD/Cassette JBL stereo w/10 speakers
-DVD Rear Entertainment System
-Navigation
When you go with the AWD, the available option packages are dropped significantly. This may have to do with weight issues and EPA guidelines.
I initially thought this was stupid packaging, but this may be an ingenious effort to drive me upmarket to an XLE-Ltd. Bastards...
Steve, Host
Survey says:
"The 2004 Toyota Sienna was the most beloved minivan in the survey"
New cars Americans love most (CNN Money)
Steve, Host
What he told me was that on a recent sub-freezing winter morning after rain the night before he headed downhill on the twisting roadbed from his home to work. After almost losing it on several very slippery turns he decided to pull over, relax, and think things over a bit. He said it was at that point that he remembered our conversation.
So he pulled back out onto the downhill roadbed, slipped the transmission into neutral and coasted all the way down to the botton of the hill with no further incidents of threatened loss of control.
Question 1: How did he expect this heavy car to behave in such conditions?
Question 2: How did FWD affect his ability to navigate this icy, twisting, downhill road? (FWIW, I tried driving on such a road, just once, with a RWD vehicle and, you know what? It didn't do any better than this FWD Caddy.)
Question 3: How fast was he driving (in gear) down this twisting, icy, downhill road?
Question 4: How did coasting down the hill in neutral improve his ability to control the car?
Question 5: Was he aware that coasting down hills in neutral is illegal (probably because the driver has less control over the vehicle)?
Question 6: When can we get back to talking about the 2004 Sienna?
The guy following in a RWD Volvo had a bit more fun. I saw his headlights disappear in my rear view mirror - he did a 360, kept out of the ditch and managed to get on down the road behind me. He was almost as good a driver as I am, LOL.
Wonderful northern lights that night, fun party, kept out of the ditch and at 6 am we hopped a plane to Molokai :-)
Whatever you do, don't let this happen to your new Sienna. Stay home during ice storms for starters! (Journal Sentinel)
Steve, Host
Go floating down the river with a drag anchor tied to the stern of the boat.
Now try the same trick with the anchor tied to the bow.
My anecdote happened in the early 80's - don't remember the vintage of the Volvo.
I still don't believe that a FWD Sienna is inherently dangerous on snow or ice.
Why are you getting an AWD one for life in Anchorage, Java?
Steve, Host
No, really, (you can guess, but) I'm getting it as awd b/c I feel that it's a better way to get around in the winter, as long as I don't put chains on the front tires only. Lucky for me, I'm getting a new set of Hakkas.
FWIW, Volvo made only rwd cars (for the US, anyway) until... 1993, with the introduction of the 850. Their last rwd vehicle was the 960, which lasted until 1997 (maybe '98?).
While I can appreciate the well thought-out opinions on the subject, I am nowhere near convinced that fwd or fw-biased awd is dangerous, with or without stability controls or other electronic gizmos. For one thing, that would be saying that Audi, Volvo, Subaru, Mazda, VW, Toyota/Lexus and a host of auto makers are producing dangerously unpredictable vehicles with their fw-biased awd systems.
I do understand the anchor analogy very well, but I also think that this is an extremily isolated and preventable situation for most any consumer. The important thing to remember is not to put chains on the front of a vehicle, but to have the same tires (and traction devices if you chose) on each corner of the car.
I believe that the Northstar Caddy actually had mass as it's enemy and not fwd, although those cars are the devil for torque steer, a decidedly fwd downside. Combine this with a non-winter tire, and I don't see how any car could've negotiated a slippery, icy, windy downhill grade with grace and poise.
Anyways, back to the original question about Sienna AWD system. Yes, the Sienna's open differential/traction control system is well proven, and effective. It is the same system used by RX330, Mercedes 4matic, M-class, BMW 3 series, and 1st generation X5. Its 50/50 torque split on normal driving (wwest would repeat his guess work on this based on his totally different RX300 which you can safely ignore) is superior to many other AWD systems which are basically FWD until slippage occurs (e.g. Volvo XC90, Accura MDX etc).
But we have beat it to death in here too; feel free to continue in AWD, FWD, RWD - Which is the Best? and check out Toyota 4WD systems explained.
Steve, Host
With equal final drive ratios I would readily acknowledge that with no tire slippage the torque is 50/50. With an open center diff'l once a tire slips, front or rear, it limits the torque to all and you're STUCK!
And now you have as little as 45 seconds of brake torque apportioning to get unstuck.
I will take my FWD Integra with 4 snows over any 4wd SUV with 4 non snows, and my car is very light with no ABS or traction control. The simple fact is the most important part of ice/snow driving is stopping, and drive wheels don't help.
Unfamiliararity.
When something untoward happens human nature is to "back-off", reverse what we just did or were doing. Therefore the instance your gut tells you the car is suddenly "out-of-kilter" your instinct will be to lift the throttle pedal.
In a RWD vehicle the resulting application of "slight" engine braking at the rear will actually aid in bringing the vehicle back into "line".
In a FWD, remembering that with driving and steering forces combined it will be most likely the front that no longer has sufficient traction, lifting the throttle is potentially hazardous.
So here is a case wherein with regard to human nature RWD is mostly benign while FWD is potentially hazardous.
One of the hardest things I ever did was learn to ignore what my "gut" and spatial vision was telling me and only rely on the instruments in IFR conditions.
I have always felt that when a dealer sells someone a FWD vehicle they should be forced to have a training class so purchasers are prepared to ignore their natural instincts on certain occasions.
It's been many years since I was in Alaska in the wintertime but what I do remember now that I think about it is that this is the time when the roads are at their smoothest, AND SLIPPERIEST!
Roadbed crack and pot-holes all filled with frozen water!
I think most of us will readily admit that it is the unexpected icy or slippery patches of roadbed that do most of us in.
I have driven hundreds upon hundreds of miles in MT in the wintertime on ice and snow covered roadbeds mostly without incident. But ALWAYS, at the end of the trip I needed some serious rest time from those hours and hours of being "on point".
I must admit, in retrospect, that my unplanned off-road excursions have been more the result of unexpected conditions, black ice, etc, than driving continuously on snow and ice.
The one car safety feature you need now (CNN Money)
Steve, Host
>The one car safety feature you need now (CNN Money)
I totally agree. Icy spots maybe, but probably not icy road, afterall, you cannot defy the law of physics.
ESC/ESP or VSC in Toyota/Lexus is a great safety feature; something which does not show up in any crast test ratings. When ever being asked, I would not hesitate to recommend it - something you should put it at the top of the list when you shop for a new car nowadays. It is perhaps one of the most under-rated safety features, and IMHO, one of the huge advantage of Sienna over Odyssey.
It seems to me that only Bill Gates knows the answer to that.
How does one quantify the value of VSC, PSM, etc, to the typical non-technically oriented automotive consumer??
In 30k miles of driving in my VSC equipped 01 AWD RX300, several round trips during the winter to central MT, I only know for certain of one time the VSC "tripped". And that one time was while in an accelerating turn through a water puddle in an empty parking lot, no big deal had the VSC not been available. With 12K miles on my 01 C4 I can't say the PSM has EVER activated.
But then I don't doubt it's actual value for saving my butt should the real need arise.
It's the flip side of trying to convince folks of the hazards of FWD!
My 04 xle is the 3rd vehicle I have owned with DIC (Digital Information Center), and also the 3rd one to show better mileage on the DIC than actual...
And i'm not in a hurry to get a new car. but I want to hear your opinions on Sienna vs. 4Runner. your comments would be appreciated. thanks!!
Steve, Host
Actually, I can remember the So. Cal. young man who had outfitted his Ody with ground effects and specially-acquired-through-a-friend Japanese LaGreat version custom parts. So, nothing would surprise me much, I think....
Yes, it is true that the first thing to go wrong with a RWD in adverse roadbed conditions is that the rear end will break traction. But then the really, REALLY, nice aspect of that would be that the front, steering" wheels, will most likely still have tractive force with the roadbed.
In the past I have been guilty of having cruise control on in circumstances wherein I should have been suspicious of black ice.
BAD NEWS!
Had I been in a FWD car when that happened I quite possibly would not be here today.
If your cruise control doesn't automatically disengage the very instant ANY tire slippage occurs, especially with FWD or front torque biased AWD, then it should be disabled permanently during the winter months.