[MrZ]

Ok so I just washed my car. After a few hours of driving, I notice there's already a thin film of dirt/grime on the rear bumper and the vertical portion of the trunk lid. After a week, there is enough build up for me to have to usually wash it again, even if the rest of the car is completely clean. The build up doesn't occur anywhere else on the car. My theory is that it's caused by grime on the road being sprayed up by the rear wheels onto the back of the car. On the flat white paint, it's *really* noticable, especially when it's sunny. Has anyone else noticed this or had this problem? How do I get around it? Hyundai don't offer any aftermarket mudflaps and they would probably spoil the styling of the vehicle (unless they were body-colored).

 

[patp811#yahoo.com]

Hmmm...have not had that problem. In fact, I had just commented to someone how the paint on this car really seems to repel the dirt - it always looks clean and shiny - even the back..The surface is just like glass...
I wonder if mud flaps would help you?

 

[eyecue]

Do you drive your car wet after you wash it?

 

[Mike Eckman]

Most likely this is caused by aerodynamics. We can add this to the list of "quirks" that this car has as a result of fuel economy.

The shape of the '11 Sonata is heavily influenced by its coefficient of drag (Cd). The more aerodynamic a car is, the less drag it has, and the better fuel economy it can get.

If you look at a car in a wind tunnel, the air is supposed to smoothly flow over the top of the car and meet up with the air flowing under the car and create a "negative" air space right behing the car. The idea is to do this with as little turbulence as possible as turbulence impacts the Cd. Unfortunately, the only way to really eliminate turbulence is to shape the car like a Lamborghini.

Since Lamborghinis make for poor 4 door family sedans, a compromise has to be met while having a shape that still has a pretty good Cd, but allows a little bit of turbulence.

It is this turbulence that "swirls" dirt around in a circle behind your car depositing dirt there. This is something that sporty cars have always had to deal wtih. My Trans Am always gets grime and dirt on the rear bumper, tailights, and underneath the spoiler.

I highly recommend getting a clay bar and claying this area of your car regularly to remove the deposits which will get into your paint and make it look faded after a couple of years.

For a list of the Cd ratings of many popular cars, check here:

http://en.wikipedia.org/wiki/Automobile_drag_coefficient

 

[jng34c]

QUOTE (PattyNY811 @ Jul 23 2010, 05:21 AM) index.php?act=findpost&pid=344078

Hmmm...have not had that problem. In fact, I had just commented to someone how the paint on this car really seems to repel the dirt - it always looks clean and shiny - even the back..The surface is just like glass...
I wonder if mud flaps would help you?

HAHA... coming from someone with a silver Sonata. Seriously that color hardly shows ANY dirt. And for the OP, yes, I do experience the same issue. I have a black GLS and it seems as though the back bumper area collects the most dirt and grime. It's annoying, but I wipe it off every time I get home with some Meguiars Quick Detailer

 

[JohnLH]

QUOTE (Mike Eckman @ Jul 23 2010, 09:32 AM) index.php?act=findpost&pid=344107

For a list of the Cd ratings of many popular cars, check here:

http://en.wikipedia.org/wiki/Automobile_drag_coefficient

While that link doesn't list the 2011 Sonata, it's Cd is reportedly 0.28.

 

[Mike Eckman]

QUOTE (JohnWho @ Jul 23 2010, 08:58 AM) index.php?act=findpost&pid=344113

While that link doesn't list the 2011 Sonata, it's Cd is reportedly 0.28.

Yeah, I recall reading that somewhere else too.

.28 Cd is good for a sports car or a dedicated economy/hybrid car, but its amazing for a 4 door family car. Hyundai really did their homework when designing this car!

 

[newsonatauser]

:innocent: I've noticed that on my Harbor Grey Metallic as well. I guess it's something that I will have to live with :grin:

 

[Flying Fossil]

I think you got one with a defective body shape and it should be covered by the warantee.

Ask your service dept. about it.

 

[snapper41]

..
Yup.. This seems to happen to me also.......But only when I come out of Warpdrive.........I just use spray bottle of quickie detailer, 15 seconds later and a wipe with a fiber cloth and its good for another gabizzillon light years.


Just the aerodynamics of the beast creating that extra large vacuum turbulence in the back of the car.

 

[03clyde]

Dirt on a car after driving it, wow. I just checked mine and it's there too. :whistling:

 

[JohnLH]

Mine sometimes gets dirty just sitting in the carport!


Factory defect? I hope the warranty will cover this.

:whistling:




Seriously, Davez621, you've pointed out something that may happen a bit on a lot of automobiles.

Just something to watch for when trying to keep it clean.

 

[MrZ]

I got the Meguiar's quick detailing spray and it works a treat, but wouldn't a California car duster be a better solution, as it's only a 1 step process it should take half the time?

I've also noticed that the wheels (18") get very grimey very quickly.

 

[louky]

i've have the white and only get noticeable dirt buildup when it rains or drizzles during the day. if it doesn't rain the whole week then my car pretty much stays clean.

 

[NT2SHBBY]

OH NOES!!!! The car gets dirty after driven, SAY IT AIN'T SO!!!!!!!!!!!!!


this is clearly a manufacturing defect.....I suggest you return the car IMMEDIATELY to Hyundai and DEMAND they purchase (at their cost of course) a Mercedes or BMW that clearly sheets dirt off as its driving and exchange it with the Sonata.


THIS IS UNACCEPTABLE!!!!!

 

[eyecue]

QUOTE (NT2SHBBY @ Aug 4 2010, 09:23 AM) index.php?act=findpost&pid=347041

OH NOES!!!! The car gets dirty after driven, SAY IT AIN'T SO!!!!!!!!!!!!!


this is clearly a manufacturing defect.....I suggest you return the car IMMEDIATELY to Hyundai and DEMAND they purchase (at their cost of course) a Mercedes or BMW that clearly sheets dirt off as its driving and exchange it with the Sonata.


THIS IS UNACCEPTABLE!!!!!

Wow you read my mind.

 

[JohnLH]

Like I said - "factory defect".

:grin:

 

[Bearcats]

You guys MUST have defects. Washed/Clayed/Zaino'd my car on Sunday. Still looks good today. So I guess if you own a Pacific Pearl, the defect doesn't apply! :whistling:

 

[ssmuff]

**** I wash and clean both cars on Sunday and by end of Monday my Sonata is a dust bunny. The Jeep is driven by the Wife so it stays pretty clean on the outside. The inside is a different story. I am used to my Sonata getting dusty since thats my field of work (Asphalt).

 

[Garnerwolf]

It's bad on my Black also. Hoping the mud flaps help when they finally get here. Otherwise just something we'll have to live with. I'd be concerned the dusting thing might lead to scratches since it's obviously more than jsut 'dust' that accumulates back there.