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Old 15th August 2016, 17:23   #16
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Default Re: Car swaying on highway - Effect of crosswinds?

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Originally Posted by apachelongbow View Post
However a parked Storme oscillates a bit when a truck or a bus pass by at high speed in close quarters.
That would be because of the road / foundation not being firm enough.
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Old 15th August 2016, 21:17   #17
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Default Re: Car swaying on highway - Effect of crosswinds?

I have Waggy F10D, Recently i was crusing on highway(BLR-HYD), even though i was at 80-100 speeds. I could feel significant Lateral movement, due to crosswinds, lateral movement gets worse especially, while overtaking HCV's.

Worthy to mention: we are 3 adults + 2 Kids with lots of luggage, still maybe because due to tallboy design, significant lateral movement.
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Old 15th August 2016, 23:01   #18
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Default Re: Car swaying on highway - Effect of crosswinds?

Tall vehicles like XUV, most SUVs and tall boys like WagonR, Santro and Celerio sway like hell in heavy cross-winds, and also when passing a large truck or bus at high speeds.

But there are some notorious spots where even sedans and 'great-handling' hatchbacks get affected. Once such spot is near the Penukonda windmills on the Hyderabad to Bangalore highway. I travelled last month on my Figo. Luckily a bhpian had travelled a couple of days before, and also another who'd ridden a bike on the previous day. Owing to their narration, I was prepared for that spot. At triple digit speeds, i felt the Figo had lost air on the front right at some spots, and on the front left at others spots. I dropped speed to below 100 and kept driving in the pitch dark for around 10 kms. After that everything was normal! Phew, some relief that was!

While on this, even on the Hyderabad ORR there are some spots with heavy cross-winds. I experienced it last week on my Fiesta. When I was overtaking a Merc SUV at triple digit speeds (legal on ORR), I suddenly felt the car drift from the center lane towards the divider. I quickly dropped speed and understood why the SUV had also dropped speed. But after a few kms, I could reach very high speeds without loss of composure.

To sum up, even the best-handling sedans and hatchbacks are no match to the mighty forces of nature. Drive with caution and be safe.

While on this topic, I wonder how the 'pull-drift' compensation on the new Fiesta would compensate for such cross-winds. I am not sure if that really works, but new Fiesta owners can perhaps chip in.
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Old 17th August 2016, 22:01   #19
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Default Re: Car swaying on highway - Effect of crosswinds?

Much has been said of crosswinds, but do
a) drive anothersimilar vehicle to find out if yours is different.
If so, also check out
a) tyres
b) steering geometry, and worn out parts.

For tyres, best to swap with known good tyres for testing purposes.

Quote:
Originally Posted by Rahul Bhalgat View Post
The crosswinds what we usually come across, can make the car roll on its suspension but it cannot make it drift laterally. Rubber (tyre) has fairly good amount of grip on the road (co-efficient of friction at least 0.5). So a lateral force of at least half of the car's weight will be needed to displace the car laterally. With ambient air density of around 1.2 - 1.25 kg/cu m, very high crosswind speeds will be needed (more than 200 kmph for Alto) to displace the car laterally.
Vehicle is not static.

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Old 17th August 2016, 22:47   #20
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Default Re: Car swaying on highway - Effect of crosswinds?

Completely agree!!

2008, swayed by popular recommendations, picked up a spanking new SwiftZxi from "My Car" just off the BOM-Poona expressway and as I drove back to Bombay, I literally cried.
The crosswinds on the curvy stretch before the first toll made the Swift flutter like a dried leaf.

The next two purchases though very unpopular (Cedia & Linea TJet) are rock steady in even the gustiest of winds.

Quote:
Originally Posted by GTO View Post
Just wanted to add that some cars don't appear to be as affected by crosswinds as others.
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Old 17th August 2016, 23:07   #21
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Default Re: Car swaying on highway - Effect of crosswinds?

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Originally Posted by Sutripta View Post

Vehicle is not static.
Yes. But even the kinetic friction coefficient between tyre and dry pavement is more than 0.5. So the crosswinds (that we usually come across) alone cannot cause lateral movement of the vehicle unless some additional lateral force is generated because of tyre - road interaction. Properly aligned, balanced and rotated tyres having proper grip won't allow the car to sway laterally.
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Old 18th August 2016, 20:26   #22
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Default Re: Car swaying on highway - Effect of crosswinds?

^^^
We are not talking of dragging a tyre across a surface.

If you park your car on a camber, it will not slide down. But if you start driving, with the steering in the same position as when you were driving on a level plane, you will start running down the camber.
Same with crosswinds. Because it comes in gusts, it needs constant correction, and is immediately apparent.

More than the weight of the car, care in aerodynamic design is necessary. I don't think the Alto K10 (old original version) ever saw the inside of a wind tunnel.

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Old 19th August 2016, 11:48   #23
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Default Re: Car swaying on highway - Effect of crosswinds?

take a look at this NZ article. http://www.drivingtests.co.nz/resour...-strong-winds/
Its surprising to see how a heavy trailer can be pushed off due strong cross winds. The slab sided area is to blame. Thinking about this I was wondering why my Storme doesn't feel that susceptible to crosswinds, then I realized that it is not really slab sided, infact the side is quite steeply sloped towards the roof, unlike a Scorpio or a Sumo. Maybe that and some aerodynamic designing could be the reason there is not much effect felt.
A quick question: If there is a heavy crosswind, will opening all windows, help lower its effect since the air is now being blocked by a lesser surface? Or will it make the car more imbalanced?

Edit: http://www.instructables.com/id/Meas...-car/?ALLSTEPS An interesting article to measure the drag coefficient of your car.

Last edited by apachelongbow : 19th August 2016 at 11:55.
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Old 19th August 2016, 15:04   #24
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Default Re: Car swaying on highway - Effect of crosswinds?

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Originally Posted by apachelongbow View Post
A quick question: If there is a heavy crosswind, will opening all windows, help lower its effect since the air is now being blocked by a lesser surface? Or will it make the car more imbalanced?
Opening the windows will reduce the effect of the crosswind. The window area has a considerable contribution to the total lateral area.

And crosswinds are not expected beyond 4 - 5 km travel at a stretch (correct me if it is not so). So for those 5 minutes, increased drag (due to open windows) shall not matter much.

The video in the NZ site also shows that the truck swung due to heavy crosswind and large and tall lateral area. It did not sway laterally.

I appreciate the truck driver's presence of mind in taking a sharp right turn to restore the balance. The toppling wind force was countered by the centrifugal force because of turn.

Last edited by Rahul Bhalgat : 19th August 2016 at 15:10.
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Old 19th August 2016, 17:34   #25
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Default Re: Car swaying on highway - Effect of crosswinds?

Quote:
Originally Posted by Sutripta View Post
but do
a) drive anothersimilar vehicle to find out if yours is different.
Quote:
Originally Posted by khoj View Post
.... and as I drove back to Bombay, I literally cried.
The crosswinds on the curvy stretch before the first toll made the Swift flutter like a dried leaf.
Quote:
Originally Posted by Sutripta View Post
More than the weight of the car, care in aerodynamic design is necessary. I don't think the Alto K10 (old original version) ever saw the inside of a wind tunnel.
For example, I owned the prev gen (classic Alto K10 2010 edition) and it did not sway too much. Yes - the effect of overtaking a large vehicle was definitely there but not too much.

Now, the new K10 that I currently own, (although having the same engine and platform, etc.) its a different machine altogether. The new K10's suspension is pretty soft - the body roll can be felt very VERY significantly compared to the old K10 and the ride is extremely bouncy, even with full luggage and load. The new K10 fares quite poorly on uneven roads and now, to add insult to injury, this swaying caught me off guard. Agreed that the tramlining effect could also have played a big part in how the car felt but at some points, it was so bad that while overtaking, the car literally had a mind of its own while picking the direction of travel and hence I had to constantly do micro adjustments to the steering.

This is why I wanted to know whether something is seriously wrong with the car or if this is a common phenomenon. At least, after all these posts, I can be happy to know that even bigger vehicles have been suffering from cross winds.

It feels exactly like this - when a wave hits a boat's side while travelling parallel to the wave - that moment of impact - the entire boat (floats) sways a few inches in the direction of the wave and later settles down - it was the same with the car, although the lateral movement was in millimeters instead of inches. But, because of the high speeds, this small movement was getting translated to a very large lateral "sway".

I think I'll have a definite answer when I upgrade stock tyres to better, fatter ones when the current ones are at the end of their life.
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Old 25th April 2022, 20:54   #26
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Default Car Swaying on highway

Hi All,

I'm a Newbie Driver, and building my driving skills by driving frequently and also by following tips shared on TBHP .

Recently,I took Nice Road in Bangalore, and while I'm driving at around 60+kph speed, at one point on the highway, I felt that the car is swaying towards left.

Is it due to the curve or crosswinds?

Need advise from the forum on preventing such events and make my drive more safe.

Thank you !!

Video : The swaying can be observed at 00:28

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Old 25th April 2022, 22:39   #27
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Default Re: Car Swaying on highway

Swaying is like a free lateral movement going back and forth, for examples, flag sway, cars cant :-). Are you talking about the car pulling to one side even though there is no input to the steering. Or do you feel its skidding ? If its the first one, get your wheel alignment checked. The second typically happens as your tires become bald. You need to describe how you feel a bit more for people to help you correctly. Typically a fast moving heavy vehicle on the opposite side might give you the felling that your car is being pushed to one side and yes that's the wind factor. However NICE road has dual lane worth of gap in the median for that to impact you.

Last edited by SR-71 : 25th April 2022 at 22:56.
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Old 25th April 2022, 22:47   #28
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Default Re: Car Swaying on highway

There are 2 possibilities, either your car's alignment is bad or one of the tyres in your car has low tyre pressure (mostly due to a slow puncture).

Low tyre pressure in one tyre will give that feeling like the car is swaying on the road or like floating towards one side.
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Old 26th April 2022, 00:27   #29
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Default Re: Car Swaying on highway

Crosswinds is only perceptible, there is no actual lateral movement on a 1 ton car running at 60 kph minimum. This too happens only on lighter cars (I felt in a 1st gen i10, not in my Corolla or S-Cross).

I believe there is either steering input or alignment is not right, going by the time you mention. Its too dramatic, even if its an alignment problem. It should be visibly noticeable in that case.
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Old 26th April 2022, 07:11   #30
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Default Re: Car Swaying on highway

Quote:
Originally Posted by SR-71 View Post
Or do you feel its skidding ? If its the first one, get your wheel alignment checked. The second typically happens as your tires become bald. You need to describe how you feel a bit more for people to help you correctly.
Quote:
Originally Posted by narayans80 View Post
I believe there is either steering input or alignment is not right, going by the time you mention. Its too dramatic, even if its an alignment problem. It should be visibly noticeable in that case.
Thanks everyone for the replies. Tyre Pressure is checked and I didn't notice any loss of pressure and also there are no alerts from TPMS on dashboard.

From the above replies, it looks like, it is due to steering input at curves.
Will check again and keep you all posted.

Many Thanks !!
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