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View Full Version : Why my car loses traction on wet road?


Greg220
11-15-2006, 02:43 AM
Ok, so I read in many places how good E90 is when cornering even in wet, etc. So I'm not sure if I'm driving it right (I came from FWD). I have a step transmission and stock tires.

So, I'm driving on a mildly wet road (after a drizzle, so no puddles) and try to make a 90-degree turn on a rather long curve at 25-30 mph. I take off the foot from gas and I keep it close to brake just in case. Then almost at the end of the curve, it seems that the rear wheels lose traction and the car starts to wiggle from side to side (well, the wiggling may be partially a result of me trying to offset for the lost traction).

I thought it was a bad luck so I tried it again... and again. And the same is happening sometimes even at 20 mph.

Am I driving my car wrong? Any advice highly appreciated :)

RGRAY
11-15-2006, 04:24 AM
If you have the performance tires, they don't do well in temperatures under 40 degrees rain or shine.

Drizzle with road dirt and grime makes the road more slippery than after a heavy rain.

Boile
11-15-2006, 04:51 AM
Ok, so I read in many places how good E90 is when cornering even in wet, etc. So I'm not sure if I'm driving it right (I came from FWD). I have a step transmission and stock tires.

So, I'm driving on a mildly wet road (after a drizzle, so no puddles) and try to make a 90-degree turn on a rather long curve at 25-30 mph. I take off the foot from gas and I keep it close to brake just in case. Then almost at the end of the curve, it seems that the rear wheels lose traction and the car starts to wiggle from side to side (well, the wiggling may be partially a result of me trying to offset for the lost traction).

I thought it was a bad luck so I tried it again... and again. And the same is happening sometimes even at 20 mph.

Am I driving my car wrong? Any advice highly appreciated :)

You're driving it wrong.
80% of your braking should be done before you enter the turn. The other 20% can be done while entering the turn, but very gradual (no sudden release of the brakes). Some people will tell you that all braking should be done before entering the turn, but I think a little extra weight on the front wheels (that's what you get when you brake) helps the car turn better.
You should be all done before hitting the apex and then gradually accelerate after the apex (again very gradual).
Practice at slower speeds until you get it right and I bet you can apex that thing at 30mph. I have one 90 degree turn coming from the highway (60mph) that I routinely apex at 30mph.

gbelton
11-15-2006, 05:41 AM
First, sign yourself up for the Performance Driving experience at the Performance Center in Spartanburg, SC. They will teach you everything you need to know about driving on slick surfaces.

Now here's som advice from the 'Lord of the Ultimate Driving Machines!" :rofl: Just bustin'!:D

To get the maximum traction in all weather conditions is to ensure you have DSC/DTC active all the time [On by default unless you change it].

Well paved Blacktop roads are the best for our current formulation of tyres; not concrete roads especially when wet or ice laced.

Taking a 90 degree turn [At suggested speed limits] on any road surface should offer the driver a comfortable, safe feeling when entering and exiting any turn.

You must have the proper tyre pressure to ensure a balanced driving experience. Your settings can be retrieved from your manual or on the driverside sidewall.

Gravel, wet leaves, uneven road surfaces will always give your RWD vehicle a wiggle or a flashing of the DSC/DTC if you are entering or exiting a turn [90 degree in your case] too fast with limited traction capability.

All that I share with you will help only if you consider [Honestly] what advice we are all giving you and get some some additional training on the proper and safe ways to drive your UDM!

A few questions. Do you have the sport option? What is the average temperature when you have this issue?

One final suggestion. When you find your car loosing traction but not loosing the direction you desire the car to go, let the car do it's job and the car will firm up through the turn. 1. Do not accelerate nor use the breaks. Just use your steering wheel to keep the direction you would like the car to go; the car will adjust and find traction at which point you will be good to go. Tryi it when the road and you are safe to do so and let us know how you do.

Good luck!

Greg220
11-15-2006, 11:37 AM
Thank you for all the answers. My car is without sports package. The outside temperature, when I noticed this problem, was about 7C (44.6 F).

I did most of the braking before the turn. Then I tried to turn without braking or accelerating (I had foot close to the brake just in case of something unexpected).

I will consider the training and I will try Boile's advice too. Thanks a lot! :)

whiskey.org
11-15-2006, 08:28 PM
yeah, never brake in a corner if you're near the limits of traction


actually in the rain, sport tires can do better than all seasons

Moderato
11-15-2006, 10:15 PM
Ok, so I read in many places how good E90 is when cornering even in wet, etc. So I'm not sure if I'm driving it right (I came from FWD). I have a step transmission and stock tires.

So, I'm driving on a mildly wet road (after a drizzle, so no puddles) and try to make a 90-degree turn on a rather long curve at 25-30 mph. I take off the foot from gas and I keep it close to brake just in case. Then almost at the end of the curve, it seems that the rear wheels lose traction and the car starts to wiggle from side to side (well, the wiggling may be partially a result of me trying to offset for the lost traction).

I thought it was a bad luck so I tried it again... and again. And the same is happening sometimes even at 20 mph.

Am I driving my car wrong? Any advice highly appreciated :)Taking your foot off the gas mid turn will transfer weight to the front of the car and you also have an open rear diff = not a lot of traction for the rear tires.

ObD
11-16-2006, 10:41 AM
1) No SP = handles like a Lexus, you've handicapped the car's potential
2) It's the steptronic. Try sport mode or 2nd gear manually. Once again you've handicapped the car's potential.
3) Get thee to a driving school ASAP.

BitViper
11-16-2006, 11:18 AM
You exceeded the coefficient of friction of the tires..... :-)

Have you tried a set of Goodyear D3's (I'm running 275, 17's) I run them on my Camaro and have NEVER slipped in the rain..stickiest tire ever made...but they'll cost you

dm5x
11-16-2006, 12:05 PM
1) No SP = handles like a Lexus, you've handicapped the car's potential
2) It's the steptronic. Try sport mode or 2nd gear manually. Once again you've handicapped the car's potential.
3) Get thee to a driving school ASAP.

I am not following your #2, and even #1 could be a stretch. He's driving through a fairly sharp turn on a wet road gradually losing traction in the rear and starts to oversteer. How exactly would keeping it in 2nd help?

pilotman
11-16-2006, 12:26 PM
This thread is hilarious.

BMW's that like Toyota products and rear ends sliding around.

Its called RWD, I am assuming you have never owned a RWD vehicle before.

I can easily bust the rear end of my e46 325 around no problemo in merely cool, wet weather. It is quite easy to do.

SLOW DOWN, and easy on the throttle through the corner.

MythMaker
11-16-2006, 03:22 PM
Okay... you guys are being a bit harsh...

I have a 325i and have noticed the stock RFT seem skiddish in the rain, but ONLY around tight turns?

Weird, I know. Around wide sweeping turns, no problem. Starting, OK for RWD + rain +HP.

Tight turns, even with no gas or brakes being applied = slippery.

Why, no idea.

AzNMpower32
11-16-2006, 03:59 PM
My advice to the OP is follow what gbelton and a couple others have said about your driving techniques. I hate to sound like a drivers' ed teacher, but driving slower on wet pavement can't hurt you; maybe you're going a bit fast to begin with. Always look where you want to go and not the ditch along the side of the road. No car defies laws of physics.

Admittedly, the run-flats really don't have much grip. When they wear out, I recommend getting a good decent set of non RFTs.

artie
11-16-2006, 04:07 PM
this is my concern regarding the 335i with performance tires....i have read conflicting stuff about this..... whether the car (rwd with performance tires) is safe in wet conditions?? more concerned about the rain (since that happens all year )round than the snow (when i will just leave the car home)... especially compared to the 328xi car? i just ordered a 335i with sport pckg but am a liittle unsure if i did the wise thing here in ny with the weather the way it is for the next few months... still have time to change the order ( to the 328xi) since it does not go in to production until dec 1 ( i believe) any advice?? thanx...

Pedal2Floor
11-16-2006, 04:29 PM
this is my concern regarding the 335i with performance tires....i have read conflicting stuff about this..... whether the car (rwd with performance tires) is safe in wet conditions?? more concerned about the rain (since that happens all year )round than the snow (when i will just leave the car home)... especially compared to the 328xi car? i just ordered a 335i with sport pckg but am a liittle unsure if i did the wise thing here in ny with the weather the way it is for the next few months... still have time to change the order ( to the 328xi) since it does not go in to production until dec 1 ( i believe) any advice?? thanx...

Performance tires will work in wet or dry provided the temp is not too low. For the winter you better get snow tires on all four corners. I would get snow tires on the car before Mid-December. We have been having warmer than normal weather in the northeast but that is going to change very soon. Just as it starts to rain or in a drizzel is the most dangerous time for any driver because the oil on the road comes to surface and nothing will help you. This is when you should procede with most caution.

You just have to use your head when driving. In wet and snow make sure you brake in a straight line. When you brake weight goes forward giving front tires more grip, when you accelerate weight moves to the rear. So, when you are coming up on a corner brake in a straight line and while still using some brake start into the turn. As you approach the apex of the curve slowing transition from brake to gas. This will move the weight to the rear and will keep your back end from swapping ends. At the mid-point of the curve you want to SLOWLY accelerate and you get to the end of the curve you want to give it gradual power. When you are perfectly straight that is when you should be giving it the most power. Part of the joy of have a near 50/50 balanced car is the physics actually works.

It does not matter if you have AWD, FWD or RWD. Go to fast into a turn in the turn in the snow or just wet road surface and you are going to go into the weeds. AWD will not allow you to stop any quicker in the snow or wet. In deep snow or very steep hills AWD will be better in getting you moving but that is where the difference ends. Your head is the most important safety equipment you own.

HugH
11-16-2006, 06:29 PM
Geez, that remids me of my '81 Z-28 car with Toyo tires. Even in the dry Texas Summer, if anyone had recetly spat on the road, making a left or right sharp turn would cause the rear end want to come around. I only kept that car for 2 yrs and no more Nissan Z-cars for me!

My 04 325 with factory Michelins is all the opposite. No matter what, I would have to do some stupid driving to make the rears want to come around!

gesoffen
11-17-2006, 04:40 AM
This thread is hilarious.

BMW's that like Toyota products and rear ends sliding around.

Its called RWD, I am assuming you have never owned a RWD vehicle before.

I can easily bust the rear end of my e46 325 around no problemo in merely cool, wet weather. It is quite easy to do.

SLOW DOWN, and easy on the throttle through the corner.

Reread the OP - he said he wasn't accelerating nor braking in the turn. Assuming compression braking wasn't a factor (considering he has step, that is a pretty good assumption) there'd be no difference between RWD and FWD. In fact, with the better weight distribution afforded by a front engined/RWD car, he should be doing better than the average FWD.

Bottomline - go to a performance driving school. These courses should be mandatory for ALL drivers in this country.

Moderato
11-17-2006, 06:26 AM
Reread the OP - he said he wasn't accelerating nor braking in the turn. Assuming compression braking wasn't a factor (considering he has step, that is a pretty good assumption) there'd be no difference between RWD and FWD. In fact, with the better weight distribution afforded by a front engined/RWD car, he should be doing better than the average FWD.

Bottomline - go to a performance driving school. These courses should be mandatory for ALL drivers in this country.Yeah but he did say he was lifting off the throttle in the turn which will cause oversteer, plus the open rear diff will mean it's easier to get one rear tire spinning when he gets back on the throttle and cause DSC to activate giving the impression of no traction for the rear wheels. BTW - not everone in this country is a bad driver.

SteveinBelAir
11-17-2006, 06:36 AM
http://cstl-csm.semo.edu/cobb/ui378/images/tos004.jpg

You canna change the laws of physics, Captain!

gesoffen
11-17-2006, 09:33 AM
Yeah but he did say he was lifting off the throttle in the turn which will cause oversteer, plus the open rear diff will mean it's easier to get one rear tire spinning when he gets back on the throttle and cause DSC to activate giving the impression of no traction for the rear wheels.

Throttle lift off will cause a FWD car to oversteer just as much (or more dependant on poor weight distribution) as a RWD car.


BTW - not everone in this country is a bad driver.

Also true. However, the majority are. I, for one, would be more than willing to fork over some of my hard earned cash for a performance driver school (whether I need the school or not) if everyone else in this country were required to take it. I'd consider it a small investment for a much safer (and probably saner) driving public.
Besides, even skilled drivers should jump at the chance to practice or improve.
I'm probably preaching to the choir but I guess I'm having one of my "If I were Governor..." moments.

Greg220
11-17-2006, 02:03 PM
I did some online research and it seems that a 1 day performance driving class costs more or less $1000 :( .

Has anyone here completed a performance driving school? How many hours was it, what was the cost and did you learn a lot?

Boile
11-17-2006, 02:59 PM
Two day event with these folks goes for $275.
http://www.thedriversedge.net/

jvr826
11-17-2006, 04:55 PM
You also need to keep in mind that the rainy season is just getting started out here in the West, so road surfaces will be extra slick for a little while.

I was out in the first rain we had in October in my 2wd pickup and the road was like ice. I could barely go over 20 on twisty mountain roads without getting the ass loose with too much throttle. Takes some finesse to keep a butt-light vehicle with a V8 planted on a slick surface.

I also highly recommend the driving school idea. Regardless if it's required or not, everyone should do it on their own. I've been driving 25 years and learn something every time I go to one. You'll be amazed at how much control you can have when you know how to properly use the steering wheel, throttle and brake. It's not something that can be talked about, you need to experience it to understand it.

I don't know about other chapters, but the Bay Area BMW CCA chapter has car control clinics and driving schools. The car control clinics let you explore vehicle dynamics in a safe environment. Throttle steering, emergency braking, slolom driving. The driving schools build on these principles and teach you smoothness, weight transfer, and the correct way to drive thru a corner. Go to one, you will not regret it!

Drive safely!

Moderato
11-17-2006, 07:37 PM
Throttle lift off will cause a FWD car to oversteer just as much (or more dependant on poor weight distribution) as a RWD car.Don't you hate having to repeat yourself? ;) I'm sorry if I gave you the wrong impression because I did get that from your last post and I obviously knew that already, but my previous statement was regarding the OP and not so much you.