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Old 9th October 2009, 12:41   #46
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hatchbacks/suvs get dirty at the back easily. atleast thats what i've seen/experienced.
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Old 9th October 2009, 17:23   #47
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Originally Posted by somspaple View Post
hatchbacks/suvs get dirty at the back easily. atleast thats what i've seen/experienced.
Yes, and the reason for that is aerodynamics. In a hatchback, the air flows over the front windshield and over the roof, creating a vacuum in its wake, and causing fine particles of dust and water to get sucked in and deposit on the rear windshield.
Now in a sedan, the airflow is over over the front windshield, over the roof, and down over the rear windshied and the boot. The last part forces rain and dust away from the rear windshield and hence it does not need a wiper/washer.
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Old 15th April 2010, 19:58   #48
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Default Rear Window wiper: Why not in sedan?

Hi
Normally SUVs and hatchbacks come with optional rear window wiper. But not any sedan why it so?
  • Staying up Rain drops residue on rear window
It depends on slope of window and generally hatchback/SUV have more vertical back frame than sedan so rain drops should slide down fast in hatch back/SUV. Keeping rear window cleaner.
  • Manually easier to clean in sedan?
No. sedan requires more arm stretching than hatchback


Some how I am not able to think why rain drop cleaning (wiper’ing) is needed in hatchback but not in sedan. How does extra box/bootspace in sedan helps and rear window wiper is not needed in sedan?

Regards/
R.D.P
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Old 15th April 2010, 20:13   #49
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Accent VIVA had a rear wiper.
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Old 15th April 2010, 20:20   #50
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So does some variants of Skoda Octavia. I think the reason is because of the boot that overhangs after the rear tyres. This reduces the chances and amount of goo that is flung from the rear tyres on to the rear glass of the car. So it is more than just what comes from above

Last edited by triedeverything : 15th April 2010 at 20:21.
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Old 15th April 2010, 20:21   #51
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Quote:
Originally Posted by Mission_Safari View Post
Accent VIVA had a rear wiper.
Quote:
Originally Posted by triedeverything View Post
So does some variants of Skoda Octavia. I think the reason is because of the boot that overhangs after the rear tyres. This reduces the chances and amount of goo that is flung from the rear tyres on to the rear glass of the car.
These two are notchbacks, not sedans.
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Old 15th April 2010, 20:24   #52
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IMHO, the rear wiper is not really for rain drops which would anyway get dried if you keep the rear deforster switched on.

What I have noticed is that due to the absence of a boot, more spray from the rear tyres gets on the rear window of SUV/hatchback which needs cleaning periodically since its a mixture of mud / dirt and water and this is when you really need a rear wiper along with wash/spray.

Also another thing I can think of that since a sedan's rear window is usually has less height compared to hatchback/SUV. This may cause a problem since you cant use a wiper long enough to cover the entire window. A short wiper would just clean a v small part of the window.

Just my 2 cents
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Old 15th April 2010, 20:35   #53
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Quote:
Originally Posted by Mission_Safari View Post
Accent VIVA had a rear wiper.
Technically, VIVA is a notch-back and not a sedan
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Old 18th June 2015, 14:06   #54
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Default Re: Rear Wiper & Washer ? Why only on hatch backs and NOT on sedans?

Bumping an old thread.

Last evening I was test driving friend's new City. It was raining and when reversing the car, I was looking for the rear wiper control and couldn't find it. No mention of it in the manual also. Finally came out and checked and I was shocked to see there was no rear wiper. Shocekd because my Punto and Polo (smaller and cheaper cars) have this and I couldn't believe City doesn't have one.

Walked around the parking lot, checked about 100 cars and found that none of the sedans have wiper in the rear window, most of the hatchbacks were having rear wipers (except for few - one Brio didn't have, there was a Ritz with wiper and another without).
In the evening checked the forum and found this thread which confirmed my finding in the parking lot - Sedans usually don't have rear wipers.
The reasons came up in the forum included cost cutting, no need because of the design, wiper spoils the appearance, it will reduce boot opening etc.

But isn't this a necessary safety feature. I find it very difficult to drive when it is raining without the rear wiper - when reversing and driving on the highway (visibility in the rear view mirror). Is this only me finding it difficult? What do others feel?
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Old 18th June 2015, 14:56   #55
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Lightbulb Re: Rear Wiper & Washer ? Why only on hatch backs and NOT on sedans?

Quote:
Originally Posted by JohnyBoy View Post
But isn't this a necessary safety feature. I find it very difficult to drive when it is raining without the rear wiper - when reversing and driving on the highway (visibility in the rear view mirror)
I guess the rear wiper assembly fouling with the boot opening can be the most logical reason for sedans not having the rear wiper provision. But in any case it would look ugly on the sedan. I personally have struggled with the absence of one in my earlier Fiesta.

Could this be a more logical reason:
Quote:
in Hatchbacks, after the boot lid there is nothing so the air flow causes turbulence and the dust+water that is thrown gets stuck onto the rear windscreen obscuring vision so to prevent that manufacturer's give the option of the rear windscreen wiper but in the case a sedan the air flow continues further from the windscreen to the boot lid so the turbulence caused is after the boot lid so the sedans in the rains will have dust over the boot lid and the registration plate area whereas the hatchbacks have it all over the rear part of the car.
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Old 18th June 2015, 15:19   #56
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Quote:
Originally Posted by JohnyBoy View Post

But isn't this a necessary safety feature. I find it very difficult to drive when it is raining without the rear wiper - when reversing and driving on the highway (visibility in the rear view mirror). Is this only me finding it difficult? What do others feel?
I think it is the second reason given by Ghodlur.

Quote:
Originally Posted by ghodlur View Post
Could this be a more logical reason:
Where did you quote this from? This seems to be the right one IMO. Thanks.

Last edited by a4anurag : 18th June 2015 at 15:25.
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Old 18th June 2015, 15:30   #57
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Default Re: Rear Wiper & Washer ? Why only on hatch backs and NOT on sedans?

The rear windscreen doesn't really get that dirty of a sedan.

Rear Wiper & Washer ? Why only on hatch backs and NOT on sedans?-photo.jpg

Here is a picture for reference. Source (My BRUTE-FORT: Toyota Fortuner 4x4 M/T [Upgraded Brake Booster & A/T Tyres])

When its raining, in a sedan, you may use the rear defogger, might help a bit if its condensed and carry a small wiper and wipe the rear wind glass screen whenever there is an opportunity. It sure doesn't get more dirty than this, right
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Old 18th June 2015, 15:34   #58
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Default Re: Rear Wiper & Washer ? Why only on hatch backs and NOT on sedans?

The LHD Octavia which was spotted testing here had a rear wiper which did not make it to the production versions though.

Rear Wiper & Washer ? Why only on hatch backs and NOT on sedans?-20130531_172004.jpg

I see cost cutting as one of the reason. Its a pain while reversing and parking when it rains heavily.
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Old 18th June 2015, 15:54   #59
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Quote:
Originally Posted by Sheel View Post
The rear windscreen doesn't really get that dirty of a sedan.
Quote:
Originally Posted by Gannu_1 View Post
I see cost cutting as one of the reason. Its a pain while reversing and parking when it rains heavily.
I feel the following could be the reason:

1) In hatchbacks, there is turbulence causing the air passing over the car to swirl around and lift up from the base and push towards the rear windscreen and go away from the car. In this what happens is the dust/muddy water gets lifted from the road and gets stuck onto the rear windscreen.

Whereas in a sedan, the air passes over the rear windscreen, goes over the boot and swirls around the boot area and is pushed away. Here the dirty/mucky substances get stuck into the boot area rather than the rear windscreen.

2) Cost cutting could be the reason.

3) Angle of the rear windscreen will not let water stay on the windscreen too.
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Old 18th June 2015, 16:30   #60
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Default Re: Rear Wiper & Washer ? Why only on hatch backs and NOT on sedans?

Water may not stick to the window because of the design. And mud/dirt may not hit because of the boot.
But when it rains isn't it needed just like the front wipers?

Quote:
Originally Posted by ghodlur View Post
... I personally have struggled with the absence of one in my earlier Fiesta.
Thank you for the company
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