Last post on Nov 24, 2009 at 11:53 AM
You are in the Acura RDX
What is this discussion about?
Acura RDX, BMW X3, Car Buying, SUV
#318 of 327 Re: BMW may want to consider being afraid. . . [steve_]
Sep 22, 2009 (2:57 pm)
What was the upshot? Why a rear wheel oddity when everyone else is going FWD?
#319 of 327 Re: BMW may want to consider being afraid. . . [pp2009pp]
by Stever@Edmunds HOST
Sep 22, 2009 (7:32 pm)
Wwest makes some good points about FWD in snow country where you can have a downshift situation and cause the rear end to come around. He can explain it better than me though.
Of course, I've had my FWD minivan up at the local ski hill some and never had trouble (usually I'm in my AWD wagon though). Not to mention 20 winters driving only FWD when I lived in Anchorage, but the storms there weren't like his experiences in Montana.
But if FWD was inherently unsafe, where's the carnage on the highways?
The AWD/FWD/4WD wars will go on and on, but ultimately it's the tires that make the real difference anyway.
In my opinion anyway.
#320 of 327 Re: BMW may want to consider being afraid. . . [pp2009pp]
Sep 23, 2009 (8:04 am)
Let's talk about ABS and why/how it works for a moment.
During panic/HARD braking on a tractive surface there is a very REAL danger of losing directional control if your front wheels begin to skid/slip due to the braking friction overcoming the tire-roadbed traction coefficient. With the tires skidding across the roadbed you have NO LATERAL control with which to deviate from the path set by the vehicle's momentum/inertia, nor the ability to hold the direction if the vehicle begins to "drift" in an undesired direction.
The same circumstance will exist if the roadbed happens to become an "ice rink", except now it is entirely possible that even the slightest level of engine compression braking, or "regen" braking, can result in an adverse effect. Engine braking that (today) ABS CANNOT abate/alleviate in order to allow you to maintain directional control.
With RWD engine compression braking occurs at the REAR WHEELS and therefore does NOT INTERFERE with the lateral traction at the front wheels. Back in my days in NH or MT (and more rarely Anchorage/Fairbanks), BEFORE ABS, if I were driving a stick shift I would often downshift and then use the clutch to moderate the level of engine braking at the rear. With an automatic I often used a very slight application of the e-brake to add a slight "drag" anchor to both slow the car going down a SLIPPERY roadbed section and to hold the car "in line".
If you should ever find yourself travelling down a fairly steep incline, SLIPPERY incline, with, as recommended, tire chains ONLY on the front wheels of a FWD or F/awd vehicle you will know, INSTANTLY, of which I speak.
If you are driving a FWD or F/awd vehicle on a wintertime adverse condition, SLIPPERY, roadbed, keep this advice from the AAA in mind. Be prepared to QUICKLY shift the transaxle into neutral the INSTANT you begin to feel the onset of loss of directional control. The advice also applies to RWD and R/awd with automatics.
Anyone driving a stick shift doesn't need to be, SHOULDN'T need to be, told what to do.
#321 of 327 Re: BMW may want to consider being afraid. . . [steve_]
Sep 23, 2009 (8:13 am)
"...downshift situation..." "..rear end to come around.."
No, the rear end coming around is really a result, "after effect", of having lost traction at the front tires, and therefore directional control, "control of direction". If lateral traction remained at the front, as would happen with the new VW technique, you could simply "stear into the skid" and thereby quickly recover.
#322 of 327 Re: BMW may want to consider being afraid. . . [wwest]
by Stever@Edmunds HOST
Sep 23, 2009 (11:26 am)
What's funny is that most of the wrecks I've seen going to my local ski hill have involved 4WD rigs and when the first snows hit Anchorage or Colorado, it's SUVs that are most prevelent in the ditches.
Maybe us FWD guys just know the limits of our vehicles better.
#324 of 327 Worth noting...
Sep 25, 2009 (12:27 pm)
The TL with manual transmission is NOT available with FWD, only SH-AWD.
#325 of 327 Re: BMW may want to consider being afraid. . . [steve_]
Nov 23, 2009 (3:58 pm)
Too many cowboys in AWD rigs and SUVs! Let's face it, most of them are too "cool' for their own good!
#326 of 327 Re: BMW may want to consider being afraid. . . [steve_]
Nov 24, 2009 (9:42 am)
"...it's SUVs that are the most prevelent in the ditches...."
Maybe because these days MOST SUV's are FWD, patently UNSAFE FWD...??
Or at best F/awd...??
#327 of 327 Re: BMW may want to consider being afraid. . . [wwest]
by Stever@Edmunds HOST
Nov 24, 2009 (11:53 am)
No, it's mostly the driver. People think they are better drivers than they really are, and when you have a 4WD or AWD you think you have another layer of invincibility and wind up driving too fast for conditions.
People first, tires second, drivetrain third.
Look at skiers. The good ones could put on a pair of sharpened 2x4s and outski me on fancy new shape skis (actually had an instructor do that to me one year at Donner Pass). Equipment isn't a substitute for skill.