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Discussion Starter #1
This is my first small hatch back, and it gets dirty very quickly on the back :(... especially in the rain ( I guess that's understandable)
Is this an inherent design of them?
 

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Common Sense
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I've noticed the same. I think I may be going back to a sedan after this (my first hatch). The number of times the hatch comes in handy is minimal. Dunno - too early to say for sure. :nerd:
 

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Yep, better get used to it. Just the way it is!

Get some mud flaps, they'll help! Rokblokz and RallyArmor make good ones for our cars. I have Rokblokz on mine, so does @BlueHaloGirl, we love em!
 
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I love my Rokblokz!!! The best way to clean the rear up!!
I found that my spoiler added to the build up of dust/dirt on my rear window but since I put a speed style spoiler on it's cleaner.
Of course changing the spoiler is not the easiest/cheapest way to fix it. Just giving some further advice.
 

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Common Sense
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Don't really see how mudflaps would help. My 2013 rear gets dirty just sitting in the parking lot, when not being driven. Along with the top of the car - much more so than the doors...
 

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Don't really see how mudflaps would help. My 2013 rear gets dirty just sitting in the parking lot, when not being driven. Along with the top of the car - much more so than the doors...
Mudflaps divert the dirt and splash from flying back and up the rear window. I'm not talking the stupid OEM flaps that are to small to do anything I'm talking rally style mudflaps and sit just above the ground.
Of course the top of your car and rear as well as windshield is going to get dirty sitting if it's raining, snowing or just crap weather.
 

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The mudflaps will help a little bit but this is really a function of the aerodynamics of the car. As you are driving along, you are creating a vacuum and as the air passes past your car, it turns back towards your car to try and fill this vacuum, this is why the rear gets so dirty. See picture below.

 

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It's more noticeable on hatchbacks just because of the flat rear back, but it's definitely more a problem with "newer aerodynamic cars" more than "hatchbacks vs sedans." Wax is your friend, but this time of year is always going to be the time of year for messy cars.
 

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Yeah, my sedan on the back gets really dirty/dust/gunked up etc after a rain storm too.
 
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Here's a better image with fluorescent particles in an air tunnel.


Basically there's a big deadspot where particles get trapped behind the cars wake.

It's worse for hatchbacks because the back end has a proportionally bigger surface area compared to a sedan
 

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Discussion Starter #16
Yup, all hatchbacks and SUVs are this way.
cheers guys, some interesting replies.

I'll give the mudflaps a try to see if improves
@miln32...must admit, I didn't notice it as much on my Volvo SUV ( no mudflaps) guess I was just lucky with that one. ;)

carry on cleaning..lol
 

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Mudflaps will help the sides of your car on rainy days and overall spreads between washing the car, but real mudflaps, not OEM or little tiny things; I'm talking about the big fat RallyArmor style.
The massive plus is not getting on your back and taking a rubbing or buffing compound to all the tar and crap your tires pick up and throw on the underside of the sideskirts.

As far as overall dirtiness on the rear window and hatch and bumper; you can't beat aerodynamics, just have to get used to it. All square-back cars are the same way.

If anything will help or make any difference, the aero package or at least a raised wing will to help separate airflow to push the wake further back. Chances are though you won't see any difference in the real world though.
 

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The hatch back does seem to get dirtier quicker than my sedans. But all suffer from some degree to it. The sedans more exhaust dirt, the hatch road dirt. I'll bet the hatch is creating a bigger rear-end vacuum while going through the air lifting the road dirt.

Anybody noticed rock dings & such on the back of their car? Time to 3M wrap the rear bumper too?
 

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Really simple solution guys....
1) remove windshield.
2) remove hatch
3) done. No more drag to cover the back in dirt.

*note there might be a few issues in my plan but it's still a wip
 

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Discussion Starter #20
Really simple solution guys....
1) remove windshield.
2) remove hatch
3) done. No more drag to cover the back in dirt.

*note there might be a few issues in my plan but it's still a wip
What a great idea...Where's my toolbox :laugh2:
 
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