View Full Version : Slip Slidy at 60 mph...
GoofyTimL
02-06-2006, 11:44 AM
Covered 1110 miles in the 300C from Friday afternoon to last night just before the Super Bowl going to northern NJ and back. Averaged about 22-23 mpg on the EVIC for three full tanks and part of a fourth.
On the way home yesterday on I-76/I-70 it was snowing and accumulating from Sommerset pass into eastern Ohio. Visibility was never worse than about 1/2 mile and traffic was moving with confidence at the speed limit. EVIC indicated outside temps between 27-30 F.
When we got west of Washington, PA we started to see evidence of accumulation on and icing of bridges. Within a stretch of perhaps 30 miles we must have seen a dozen or more vehicles that had careened into the median, and in some cases it was multiple vehicles... often starting upon the overpasses, etc., and leaving the road on the other side. In a couple cases the vehicles had gone into and/or through the guard rails on the other side after traversing the median.
In the midst of that section, we were tooling along and I was thinking how sure footed the 300C had been up to that point (compared to those less fortunate), when all of the sudden on an slightly curved overpass the rear end began to come around (quickly). We were doing about 60 mph as the snow and conditions had seemed to improve a few miles before that. There were no other cars within 10 lengths in front or behind me at the time. I counter steered and felt the ESP come into play, applying corner brakes and cutting engine power somewhat. I had come off the pedal and touched the brakes to release the Cruise Control (it might be that CC contributed to the break of grip, but I can't confirm).
I found it a little counter intuitive to regain control with the ESP as active as it was. The net effect was that I felt I rocked/yawed more times that I wanted, or might have if ESP had been "off" as I regained control and straightline driving. I know ESP off is not truely off, but at least it's not "as" intervening. All in all the car was back in normal operation and direction within 10 sec (I think). But it was interesting while it lasted! With no disrespect to the ladies here, but had my wife been driving instead of me, in the same circumstances... I think we would have been one of those in the median or worse. She's a Calif. gal and just doesn't have, nor want, the mid-west winter driving experience that I've had.
I will add also that we still have the ContiSelfSeals and some of the looseness may have been attributable to them. However, I can't confirm and haven't yet had the time or the snow covered parking lots around home to adequately "test" these tires. I can say only that from a wear standpoint, at 20k miles they seem to be performing well... and based on that I would expect to get at least 40k miles from them... not great, but significantly more than what I've heard from others on these forums.
Well that's it... glad to have made it home safely... and still glad I bought a 300C!
rickcrocetti
02-06-2006, 11:53 AM
I put on the Good Year Assurance tires. The car seems to perfrom well with them. However I only had one occasion to really test it.
Hemi31
02-06-2006, 11:57 AM
Sounds like an E ticket ride.Glad to hear you got her straight and she performed well.
quarky42
02-06-2006, 01:21 PM
I've read in a couple places on the forums that when you press the brake with ESP off, it actually goes back into it's more aggressive "nanny" mode as many have lovingly (sarcasm) called it. Perhaps next time you should turn off cruise control with the lever and see if that makes any difference in ESP control? Might be interesting to find out.
jtkirk
02-06-2006, 01:54 PM
I don't know much about the ESP system, but here's the first thing that came to mind when I read GoofyTimL's post:
"I counter steered and felt the ESP come into play..."
The ESP would have interpreted your turning the wheel as 'I want to face that direction'. Then it would have played steering, braking, and throttle games to try to get you in the direction it thought you wanted to go.
While a more experienced driver knows that doing the non-intuitive gives you faster control, I doubt the ESP knew what you were doing.
My bet is that if you had steered away from the yaw, instead of into it, the ESP would have countersteered first for you, then corrected course once the tires had grip again.
GoofyTimL
02-06-2006, 02:12 PM
I don't know much about the ESP system, but here's the first thing that came to mind when I read GoofyTimL's post:
"I counter steered and felt the ESP come into play..."
The ESP would have interpreted your turning the wheel as 'I want to face that direction'. Then it would have played steering, braking, and throttle games to try to get you in the direction it thought you wanted to go.
While a more experienced driver knows that doing the non-intuitive gives you faster control, I doubt the ESP knew what you were doing.
My bet is that if you had steered away from the yaw, instead of into it, the ESP would have countersteered first for you, then corrected course once the tires had grip again.More experienced driver? Sorry... there is no way I would have steered away from the slide (in my mind to cause a greater, faster 180 or 360 spin)... at least without a "LOT" of practice on an open parking area (pun intended with "LOT") to counter my 53 years of RWD experience on snow and ice. On the other hand, I agree that the ESP is more for those who don't know what to do and it's responses in combination with an experienced driver (what I think of myself) may not be the "best" combination.
I may not have explained myself well, but when the rear breaks free and is coming around to the left (drivers side) with a trip to the overpass guard rail or median looming as a near immediate result of doing the wrong thing... I'm naturally going to steer (to the left) in the direction the tail is going to try to keep the front end of the car ahead of the back end. I know to get off the gas, but not jam on the brake to try to regain tire roll and grip, then gas to apply mild power out of the slip.
magnum lover
02-06-2006, 02:26 PM
Glad things turned out okay. Personally, I would have had CC off when I saw other cars off the road, knowing road conditions were iffy, whether your car was sure footed or not since apparently others weren't. I'm not used to the ESP and traction control yet, so it does almost seem like a battle with what you want it to do and what it's going to let you do. I also have GY Assurance tires but find they can loose grip as well.
GoofyTimL
02-06-2006, 04:18 PM
Glad things turned out okay. Personally, I would have had CC off when I saw other cars off the road, knowing road conditions were iffy, whether your car was sure footed or not since apparently others weren't. I'm not used to the ESP and traction control yet, so it does almost seem like a battle with what you want it to do and what it's going to let you do. I also have GY Assurance tires but find they can loose grip as well.Yea... overall I probably was a bit slow at coming off the Cruise Control... so I did learn (or relearn) something! I had been paying attention, and had not had any indication of a CC-related issue prior to that on the regular pavement or overpasses.
So I don't really think the CC "caused" the break in grip, and as soon as the back wheels began to spin I think the CC reaction cut power to slow the powertrain... but I don't know that for certain. But if it did, it was the same reaction I would have made and probably 0.5 sec faster than my foot reaction would have been.
i never use CC when it's slippery out, it's asking for trouble imo.
if you hit a bunch of slushy snow, and it will slow the car down, but you've told it to keep going at x mph, it will increase power to the wheels to try to speed up, and away you go. going up and over an overpass will cause the car to increase throttle, then you hit ice and it will continue to try to increase power, and away you go. maybe the esp will override it, but im not about to be the guinea pig and find out ;). i was on a couple hour trip yesterday with high winds and fresh snow, normally i use cc whenever possible, but not at all in 4 hours round trip for this drive.
JamminWagon
02-06-2006, 07:57 PM
I was traveling and didnt realize the roads had iced up with CC on. Since my truck didnt have positrack/lock the free wheel will spin like crazy as the other one had traction still. It slid me sidways. From then on, I never use CC unless the road is absolutely dry.
Bandit
02-06-2006, 08:07 PM
It was more likely than not attributed to the cruise control. Glad it all worked out ok for you... bet your heart was a-thumpin' for a while afterwards!
bigjim
02-06-2006, 08:08 PM
Goofytim did you notice the yellow traction indicator flashing or the cruise stalk light off after the dance? The cruise turns completely off when the ESP has intervened fully. I say fully because it can do a BRIEF intervention (Nanny induced throttle reduction WITHOUT brake steering) and not turn off the cruise. To use cruise again you would have had to start from scratch and turn it on again. The first times this happened I thought it was my imagination that it was completely off. I have played with My Mag RT quite a bit this winter (not enough snow to do much snowmobiling!) and have noted that it comes out of a slide easier if you use the accelerator to steer rather than the brake. Of course this is when it is possible to speed up. By your description of the situation this may not have been a good idea. Sounds like a snowy trip to the parking lot is called for in any case. I am glad to see someone that has been driving longer than I have lived (47 years) still enjoys the driving thrills of the 300C! This makes me look forward to the next 30 years!
GoofyTimL
02-06-2006, 10:53 PM
Goofytim did you notice the yellow traction indicator flashing or the cruise stalk light off after the dance? The cruise turns completely off when the ESP has intervened fully. I say fully because it can do a BRIEF intervention (Nanny induced throttle reduction WITHOUT brake steering) and not turn off the cruise. To use cruise again you would have had to start from scratch and turn it on again. The first times this happened I thought it was my imagination that it was completely off. I have played with My Mag RT quite a bit this winter (not enough snow to do much snowmobiling!) and have noted that it comes out of a slide easier if you use the accelerator to steer rather than the brake. Of course this is when it is possible to speed up. By your description of the situation this may not have been a good idea. Sounds like a snowy trip to the parking lot is called for in any case. I am glad to see someone that has been driving longer than I have lived (47 years) still enjoys the driving thrills of the 300C! This makes me look forward to the next 30 years!I reacted immediately and the road and drift had my full attention forward. I have no idea whether the ESP light came on in the button or whether the skidding car light came on the dash. And now I can't recall whether I had to trip the CC back on or not. But I definitely felt the ESP hit the brakes on different corners as the back end swung back and forth (less each time) as I regained control, so I'm sure that ESP was fully engaged.
I'm definitely going to practice some in a parking lot if and whenever we get enough of a snow accumulation around here. Unfortunately in that experience it won't be possible to get up to highway speed, but things should behave similarly at boulevard 35-45 mph I would think. May have to have ESP button off to begin the experiment and then kick it in, or something... who knows?
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