'Splain me some Traction Control

[j44ke]

First test of the snow tires this weekend. Drove from Woodstock back to Hillsdale in a heavy snowstorm with plenty of ice underneath. Did fine but filled the wheels and wheel wells with snow that froze and made driving the next day ridiculous. Needed a pressure wash with hot water, but they were closed "due to weather". Huh? Really?

Anyway, I had a feeling a couple times that I couldn't get the car to do what I wanted it to, especially when dealing with inclines. One incline was just too much for the car, and it actually started to go backwards, which was mysterious to me. This was a road up to our friends' house so not a major thoroughfare and steeper than most roads would ever be. I thought for sure the car would go up it, but it seemed to progressively lose momentum and then just stopped and slid back a bit.

Reading through the owner's manual (huh, who knew all these buttons and stuff weren't just decoration?) I think I should have turned off the traction control and that would have made the car better on the hill. Of course, then I would have needed to get back down later in the evening so probably better I didn't drive up. Our friend has a big 3/4 ton dually with a plow on it, so we parked at the bottom and he shuttled us up and back.

Survey says?

[Tom]

Sumpin wrong with that traction control. With new snow tires on a Volvo C30 one can accelerate from 40 to 70 uphill in 8 inches of packed snow between the two plowed lanes on US Rte 7 southbound between Manchester and Arlington Vt to pass the white-knucklers with that little yellow triangle on the dash lit up the whole time. I know from personal experience.

[big boom]

Coming from a northern climate where we have snow on the ground 6 months out of the year I will confirm that driving on ice and snow are completely different beasts when it comes to how traction control kicks in. Traction control essentially kicks in whenever it senses slippage in a wheel based on wheel speed. Depending on the car you drive what typically happens is when a drive wheel slips, power to the wheel is neutered so that there is no more slippage. Problem is when you are on ice typically the other drive wheels slip as well which causes traction control to neuter power to all of the wheels in alternating sequences effectively rendering your car useless. You have to turn off traction control in this situation just to get power back to the drive wheels.

[j44ke]

Coming from a northern climate where we have snow on the ground 6 months out of the year I will confirm that driving on ice and snow are completely different beasts when it comes to how traction control kicks in. Traction control essentially kicks in whenever it senses slippage in a wheel based on wheel speed. Depending on the car you drive what typically happens is when a drive wheel slips, power to the wheel is neutered so that there is no more slippage. Problem is when you are on ice typically the other drive wheels slip as well which causes traction control to neuter power to all of the wheels in alternating sequences effectively rendering your car useless. You have to turn off traction control in this situation just to get power back to the drive wheels.

Yeah that's exactly how it felt. Like I was losing wheels one by one.

The traction control feature is a couple levels down in the menu on the dashboard screen instead of being a button on the dash which is what it should be. Memorizing that for next time presently.

[thollandpe]

I also learned that lesson not to drive in deep snow, pack up the wheels, and park the car in very cold temps. In my case the ice froze inside the rims at the bottom, and created a severe imbalance. It was wild. Made for a crappy drive.

Maybe yours screwed up the optical sensor for the ABS and traction control?

But heck yeah disabling the traction nanny has to be in your bag of tricks, especially for climbing hills fast or other situations where you'd like a little wheel spin.

TH

[dgaddis]

Most cars just cut power all together when traction control kicks in, either spark or fuel. You need some fancier-than-average differentials to cut power to individual wheels.

[j44ke]

Seems like Sport Mode reduces Traction Control automatically. Sport Mode is a simple flick of the transmission lever.

[dgaddis]

Yeah, it'll basically let you get some slip before it shuts down the party.

Don't forget stability management, which depending on the car may be tied in with the traction control. Stability management will (depending on the car) shift power around to different wheels or cut power and/or apply the brakes to certain wheels.

On our Honda's the traction control and stability management are all tied together as one system and can be shut off with the press of a button. My pickup does have a 'snow' mode that essentially allows some slip under power. Living in GA, I haven't had a chance to try it yet....

[j44ke]

Most cars just cut power all together when traction control kicks in, either spark or fuel. You need some fancier-than-average differentials to cut power to individual wheels.

I should clarify - this is a front-wheel drive Volvo, not all wheel. So it was just the front end that "disappeared".

Yeah, it'll basically let you get some slip before it shuts down the party.

Don't forget stability management, which depending on the car may be tied in with the traction control. Stability management will (depending on the car) shift power around to different wheels or cut power and/or apply the brakes to certain wheels.

On our Honda's the traction control and stability management are all tied together as one system and can be shut off with the press of a button. My pickup does have a 'snow' mode that essentially allows some slip under power. Living in GA, I haven't had a chance to try it yet....

Volvo calls it Electronic Stability Control. It includes traction control, spin control, active yaw control, engine drag control and corner traction control. Sport Mode increases the threshold at which ESC kicks in but doesn't turn it off entirely.

[dgaddis]

I should clarify - this is a front-wheel drive Volvo, not all wheel. So it was just the front end that "disappeared".

Sounds like it just cut power. Some (I think) apply brakes, without cutting engine power, because that way when it lets off the brake the engine is still pumping out power. Whereas if you cut power, it takes a few seconds for it to come back.

My Civic Si cut power. My first time at the drag strip with it, I forgot to turn off traction control. Set it at 3,000rpm, dumped the clutch, got a fraction of a second of slip...and it just DIED. It didn't actually die, but it bogged down so much I thought it was going to stall. When I went auto crossing, always turned of the traction control system, 'cause it's basically a party killer when you're trying to have fun. It didn't have a sport mode, it was on or off.

The one time I drove it in some snow/ice I turned off the TCS system. I very quickly realized I wasn't going to get to work that day, but then I couldn't get back into my driveway, which is almost dead flat haha. The car was lowered, and the curb/dip at the front of the driveway meant I had to go slow into the driveway. And with the ice, and the slightly off-camber driveway, the car was trying to drift over into this giant bush.

I ended up putting it reverse and was able to get in no problem.

[guido]

If you are going up hill on ice once you exceed the adhesion limits, so the tires spin, you no longer can provide more forward force than gravity is applying so the car goes backwards. The sensation the front end "disappeared" suggests you were just in deep understeer... A front wheel drive car under-steers when too much throttle is applied. A rear wheel drive car over-steers with the same input...

Conditions like that call for a sensitive foot or short of that studded tires. Or maybe both.

Relying on fancy technology in conditions like that can be dangerous... Practice is the best solution. Find an empty large parking lot and practice putting the car into and out of a skid... Every car/tire combo will behave a bit differently...

[theflashunc]

Some cars, depending on model, have a winter setting for the traction control as well, or a recommendation in the manual if you're installing chains and whatnot what level to set the traction control at.

[j44ke]

Yeah no over throttle. This isn't about not knowing how to drive in the snow. It is about knowing how to drive and the car doing something different and unexpected but now makes sense.

In my defense, the Volvo manual is not entirely clear. For example, in the first mention of sport mode, it has this:

To switch to Sport mode:


Sport mode remains active until the driver switches it off in the menu or until the engine is switched off. ETC will return to normal mode when the engine is restarted.

Hmm. Something is missing.

Later in the transmission section, it tells how to change into Sport mode, but it calls it Geartronic. Then a couple paragraphs later calls it Geartronic Sport mode. And a paragraph later, it explains that

Selecting 3rd gear in Geartronic’s manual shifting mode can help provide better traction when star- ting off on slippery surfaces.

To get into Geartronic's manual shifting mode, you have to put the car into Sport mode first. So translation - use Sport mode on slippery surfaces.

I am sensing that Volvo is making this a bit twisted, because all those features are bundled together and perhaps linked together mechanically/electronically, and since they are ostensibly "safety features" they don't actually want anyone turning them off.

[rwsaunders]

If it means anything Jorn, I’ve had the same thing happen in my Oddysey (front wheel drive) with a new set of Blizzaks on all fours and driving up a 10% icy grade. No traction control buttons to play with...just 4,300# of minvan hell deciding that gravity and the inability to gain traction were going to combine to scare the daylights out of me.

[thollandpe]

Most cars just cut power all together when traction control kicks in, either spark or fuel. You need some fancier-than-average differentials to cut power to individual wheels.

The traction control that I'm familiar with handles a spinning wheel by applying the brake to it. It's accompanied by limiting the input power. Are there any systems that only cut power? That seems like something I'd never want.

TH

[dgaddis]

The traction control that I'm familiar with handles a spinning wheel by applying the brake to it. It's accompanied by limiting the input power. Are there any systems that only cut power? That seems like something I'd never want.

TH

I know my Civic Si did. It was a total buzzkill. I'm not sure if it cut fuel or spark, but it cut something.

[j44ke]

I have to go re-find the section in the manual, but I am 99% sure Volvo says it reduces power progressively - in other words, the more the wheels slip the slower you go. Going up a different much more gradual snowy incline that my car was climbing just fine - though obviously with a bit of slip here and there - the car did slow as it went up even though I was pressing the accelerator to keep up momentum. I am really a bit surprised at the system, because it seems to do the opposite thing from what I need in a dangerous situation. Now that I understand it better, I am turning it off whenever I need more control due to the conditions.

[s_curran]

We have a manual crosstrek. Traction control goes off in the snow now. We had a interesting night on a steep icey road at 1 am in vermont. I started loosing too much speed about half way up, when it got up to the 20% grade bit, the car started stalling due to lack of power, I quickly turned the traction crontrol off and made it up to the house, a bit sideways the whole way. Of course the driveway had a giant pile of snow/ice in front of it so stupidly I stopped. Everytime I tried moving I slid about 10 feet back, traction control would instantly stall. I eventually melted enough ice down to the sand with my tires and slid into the driveway.

I wont use traction control in snow again, and we bought snow tires later that weekend.

[dgaddis]

Traction control systems aren't really designed for carefully driving in the snow. They're designed to keep idiots who have no idea how to handle a car from crashing when driving like an a-hole.

[bigbill]

Traction control systems aren't really designed for carefully driving in the snow. They're designed to keep idiots who have no idea how to handle a car from crashing when driving like an a-hole.

When I lived in the PNW 07-12 I started with an F150 4X4 and it did great on the snow, mostly because of ground clearance and the twelve 50# bags of gravel in the bed. Then I got a Subaru Forester and had to change my driving style. I lived on a steep road with a 15-18% grade and with the truck, I'd ease out of the end of the driveway and apply smooth power to go up the hill. With the Forester, I'd turn up the hill and floor it. If I hesitated at all, I'd lose momentum and traction and slide backwards. I really missed the truck after the first winter with the Suby.

If I got on an icy hill with no good traction with the truck, I'd rip open one of the bags of gravel and spread it.