Losing control of rear end of RWD car in rain

[chas3]

steer in direction of skid (the direction the rear of the car is heading, or keep your front wheels aligned with the road whichever makes sense for you). prepare for over correction on your part. if you over correct, its a skid in the opposite direction.

reduce power to wheels (take your foot of the gas). do not 'bury' the brakes. this will cause a complete loss of steering control. this is why we have abs. though, if you have 4 wheel abs, feel free to bury the brakes.

check your tires. air pressure and tread depth.

 

[Audi Junkie]

I had the same problem on a 1995 BMW 325 that someone gave me. I did not like the sensation at all. I blame the tires, Generals. Better tires run at 30-32psi would be the way to go.

 

[ediamiam]

What kind of tires you running with ? Performance tires that are great in the summer, or when dry ? Or all-season types ?

 

[tdi-rick]

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What I am unclear about is whether I let my foot off the gas or keep on accelerating.

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Basically, you reduce the input that creates the loss of traction, in this case, the throttle. There is a fair chance that if the road is that slippery and you kept your foot into it, you would have also gone right around. A more advanced driver may have been able to feather the throttle a bit and actually balance the car on the throttle, holding it with just the right amount of oppy lock. This is what every race car driver in the world does. Every quick race driver is pretty much out of control on every corner of every lap, balancing the amount of front and rear slippage between the throttle, the steering wheel and brakes.

Truly, the amount of lock and the amount of throttle to use in any gven situation can only be determined through lots and lots of practice. You are trying to programme a computer (your brain) into making it a reflex response. And Shannows advice on locking up the brakes when all is gone is very sound advice. When starting their race careers, the truly fast tend to spear off the track a lot, and one of the first things you learn is to lock it up when you've totally lost it. "if you're gonna hit something, hit it softly" used to be the mantra, and most times you'd scrub off enough speed not to hit anything at all.

 

[tdi-rick]

quote:

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(heck, it can be induced in a FWD car on snow at under 10 mph)

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ummm, every FWD I've driven (admittedly not many) were all lift off oversteery types at any speed. A few mates have had a heart starter when they have had a afair bit of understeer at speed, (way too fast for public roads) lifted slightly to tuck the nose in, and had the rear end try to meet the front. I've used it to great effect on dirt roads, and the beauty is that as soon as the rear swings lots of throttle with your correction keeps you driving forwards.

I suppose the bottom line to all of this is that all cars have slightly or greatly differing handling characteristics, and it pays to know what they are and how to respond to them as emergency situations will always crop up in general driving.

Of course, some of us will induce these characteristics at silly speeds just for the chance to correct them 'cause we never did grow up.

 

[JHZR2]

quote:

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Limited slip works well on mixed traction surfaces where the slip is momentary, but they tend to break the rear end loose on uniformly poor traction surfaces. Breaking the rear end loose with a limited slip, a lot longer stopping distances with ABS, poor acceleration with traction control, etc., all suggest better tires are needed, maybe better weight distribution, and maybe a bit more finesse with the throttle.

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An E30 BMW is about as balanced as it gets weight and handling wise... Even the battery is in the trunk for weight purposes. No traction control, early bosch ABS... the biggest problem, which you hit square on, is that the tires for the aging E30, a p195/65 (or 60, depending upon year) HR-14 is geting harder to find in a good tire.

My mention when asking about the 3.73 LSD wasnt that the LSD would necessarily help much in terms of traction, but a 3.73 diff can be a bit jumpy, even though BMW is about as good as they come in the department of matching engine output to trans and diff gearing... Ive always found it simpler, regardless of setup, to carefully modulate with a less aggressive rear end ratio. Maybe its just me though...

JMH

 

[Mitch Alsup]

In between rain storms the oil, grease, and crud falling off cars and trucks, seepw into the tarmac and stays there.

When the first rain happens, all of this stuff floats off the tarmac and creates very slipery situations.

The longer between rains, the more of this slipery stuff accumulates.

Living in LA means that it probably has not rained in (basically) forever; giving plenty of time for the oil and grease to accumulate.

I suspect you just got caught off gard, and were not thinking of feeling for traction with your throttle foot, nor were you ready at the wheel when things got interesting. I love driving RWD vehicles in low traction situations, everything from trucks to sports cars give me adequate feedback on what is happening at the contact patches--at least when I bother to drive instead of simply steer.....

 

[DaveInLA]

You're right-- it hasn't rained here in forever, so things definitely got interesting.

I've actually been in minor slippery situations in this car before in the rain, but I've always been able to maneuver my way out of them. Most of them were after 90 degree turns at relatively low speeds, on level ground. This one was going uphill at about 30 mph.

I need to change tires, but that's $$$, which I don't have.

 

[Jim 5]

I spent my 16-22 years taking every corner in a fishtail 4 months of a year on icy/snowy roads(there is ONE advantage to a Canadian winter). In your situation, I recommend high performance driving school/track days.

While icy roads are the easiest to induce fishtail, that's not an option where you live. I like the advice about going to a gravel parking lot and practicing. Some deserted gravel roads with really shallow shoulders are also good. I'd call that step 1. Rainy tarmac practicing in a safe environment will offer quite a bit more grip, and you'll need more speed/power to induce fishtail....a relatively safe environment is an empty parking lot, with no curbs, etc or a track day (but it's tough to schedule rain). Stage 3 is dry tarmack. You need more speed/power and things happen really fast here...often way too fast...I'd really only try this in a driving school experience, and after alot of safe practicing in gravel and wet tarmac.

Just remember, things happen really fast on tarmac if you get into a skid (especially dry). It's not a smooth or gentle transition. As they tell you over and over on track days in high-performance driving school, it's usually the second fishtail that kills you. You over-correct for the first-one, and the second one is far worse. Even when you're expecting it, the fishtail and snap-back can hit you pretty hard.

Whatever you do, there is absolutely no substitute for practicing....alot....in a safe environment. It has to be second nature..when you need these skills, you won't have time to think about it.

This may save your life someday!

Also...it's fun.

 

[DaveInLA]

Cool. Trouble is, in LA, there are no "safe" practice spots. There are no gravel lots, all the parking lots have stumps/curbs, and all wide roads have lots of cars on them (unless middle of night, but I'd rather not do that).

 

[Audi Junkie]

What is the tire size anyway? You probally could tweak it down 1/2 size profile and a full size wider.

 

[DaveInLA]

Tire size is 195-65-14. That's stock size. I'm going to go for 205-60-14 when I change my tires, that's a size a lot of people go far. 215-60-14 would be closer to stock in terms of circumference, but nobody does that and and there isn't a whole lot of variety at that size. Wheels are 14x6.5".

 

[qezel]

e30's, like all semi-rear trailing arm bmws love to slide... the e30's a bit more tame than some the older e21 3 series and the 2002, even more so than the more powerful e24's and e28's.. but when BMW had those semi-rear trailing arms.. they were kinda designed with sliding in mind, thats how you drove fast back in the day before you had insanely sticky tires to allow you to stick and go fast, you had to steer more with the throttle then.. the last thing you want to do is panic and quickly counter-steer while lifting the throttle, possibly with some braking in there.. if you do all of that, you're almost subconsciously performing a scandi flick.. a flick of the steering one way then quickly back, an abrupt lift of the throttle to unweight the rears... go drive in a parking lot with some snow, go slow enough so you won't get yourself into trouble and so you'll stay calm and recreate the situation you were just in.. you'll find that if you keep your right foot more neutral so you dont transfer any weight, and reel the slide in by fluently counter-steering, that e30 of yours will straighten out after a beautiful slide, it's not a sticking monster like later multi-link cars that snap and lurch at loss and gain of traction... once you get more comfortable and want to have some fun in a snowy parking lot.. you'll also find that if you ease on some more throttle, you can extend the slide quite controllably.. i know a lot of people said some of this, my main point is don't dump the throttle and be fluent with your steering.. if you're in real trouble and have given up trying to fix it, i'd say just stomp the brakes, but then its up to physics to help you avoid anything.. i've also been told.. "when in doubt, take both feet out".. leave the pedals alone and just steer.. if you should feel comfortable sliding in any rwd car.. its gonna be an e30.. and if thats not for you, get an audi quattro.. the fear is taken out of sliding quite quickly

 

[Shannow]

Funny this thread popping back up.

I'm playing in an E30 these days.

My old Toranas (double "A" arm front end, 4 link rear, upper links @45 degrees for diff centreing) used to hang on, get light up front, and then snap out sharply.

The E30 sort of feels like the rear in on chewing gum at the back end under the same circumstances. No sudden messages, just an increasingly movable rear end...when it rains, my missus won't let me out "to buy a loaf of bread".

 

[Steve S]

Don't drive so fast. Learn how to use the gas pedal.

 

[msparks]

Anytime I drive in snow or ice I will "check" my traction by breaking the rear end loose. My ex-wife hated as she thought I was goofing off. Actually knowing the amount of traction ahead of time is what I was doing.

Anyhow like others have said, turn the wheel in the direction of the skid and it will correct. If you have ever seen a flat track motorcycle race you will understand how it works. It's awesome to watch those guys slide around a track at 90+ mph.

 

[rpn453]

Come to Saskatchewan some winter and you can attend our standard high school driver training: fishtailing all over town in a RWD beater or pickup truck!

The abundance of FWD cars these days has likely made this a less common pastime in the cities (farm kids still drive trucks), but e-braking may compensate for the otherwise lost skills.

I had to do the "bury the brake" method once in my younger days when I was e-brake fishtailing a FWD around corners and one of the drums didn't release (I later determined the shoe was down to the rivets and would stick in the groove it had worn into the drum). I got control of direction but not rotation so I locked all the wheels up and continued spinning down the street between some parked cars. Not an enjoyable experience!

 

[SSerian]

I have instructed driving clinics for rallycross and other events. Think of skids this way. When the rear end steps out, it’s the back of the car trying to outrun the front of the car.

Skid in RWD car
let off gas, steer in the direction of the skid like the drift cars. Do not hit brakes! By hitting the brakes, you slow the front tires (most cars are front bias) and exacerbate the problem.

Skid in FWD car
Give more acceleration/ gas. By inputting more throttle you engage the drive wheels (front) to “pull” the front of the car back in line. Again, do not hit brakes! It makes the problem worse and you risk loosing traction to the front wheels all together.

Skid in AWD car
WE’re ALL GUNNA DIEEEEIIEEEEEE!!!!!
Hope and pray.

Seriously though, floor it. Let the AWD system pull you out of the skid. That’s what it is there for. If you let off the gas or hit the brakes, the front end will “plow” or lose traction. Your best option is to floor it.

I had a Wrx that I rallycrossed. Going into corners I would let off the gas to set the car, throw the wheel into the corner and transfer the weight to the outside tires initiating a mild skid on purpose only to floor the throttle and catch the car as it started to slide. This method resulted in better cornering ability with its setup. It had a tendency to push in corners and plow the front end. I countered this by flinging the car into curves.

 

[gathermewool]

And the necromancer of the year award goes to!!!

Seriously, 12 years is pretty good.

 

[Ws6]

As I was driving up a slightly curvy hill up to my home, I lost control of the rear end of my 1989 BMW 325is. I was completely sober.

It rained in LA yesterday, but when I was coming home late last night, the ground was mostly dry, maybe a little wet. Anyway, I normally shift a little earlier in the wet, but I figured that the ground was dry when I took the car to about 3500 RPM in 2nd gear (shifted from 1st to 2nd at around 2500). At this point, the back end just fishtailed out and scared the **** out of me. The car ended up maybe 135 degrees from the direction I was going (not quite a full 180). During the spin, I really thought I would hit something, but I was lucky to come out of that incident unscathed.

I plan on going to a track in February, which would be my first time. When one starts to feel the rear slip a little, are you supposed to turn the steering wheel in the same direction as the slippage? I've seen some clips of this, and it seems to create a "drift" that's easily corrected. I was foolish enough to simply hit the brakes, which probably made matters worse. I've only been driving RWD for 2-3 years, only a few thousand miles per year, and almost never in the rain.

thanks

My 370z abs screwed me once. Hydroplane at 65. Front got loose, wo I got off the throttle. It didn't settle so I ever so slightly apply the brakes...abs freaked and popped them and the car instantly swapped ends, and continued down the freeway for a quarter mile in reverse. I stabbed the clutch and sat back and rode it out. No harm no foul, luckily. Was trying to gently shift weight forward and settle with some bite. E nanny got me.