BMW M5 Forum and M6 Forums banner

1 - 20 of 23 Posts

·
Registered
Joined
·
1,198 Posts
Discussion Starter #1
When I go to wash my car after a week or driving I see little black particles/dust all over the rear of the car. Looks like it might actually be stuff from the exhaust. Anyone else get this?
 

·
Registered
Joined
·
9,355 Posts
I noticed that this car gets dirtier on the back. For example, when I clay it, there's more stuff coming off the back of the car than from the hood and front bumper.

Most of the time, I notice that it's dirt from the road, though. I never looked for black stuff that might come off the exhaust, although it wouldnt surprise me, either.
 

·
Registered
Joined
·
1,980 Posts
It is exhuast soot, it builds up from the slow drive in traffic.

I get it on the front end when following a LMB M5 down the highway:hihi:
 

·
Registered
Joined
·
1,198 Posts
Discussion Starter #5
It is exhuast soot, it builds up from the slow drive in traffic.

I get it on the front end when following a LMB M5 down the highway:hihi:
I like your humor Nathan!

Yep, the back of this car sure collets the dirt. I think the way the air comes off the back causes it to swirl around and stick to the back.
 

·
Registered
Joined
·
1,980 Posts
I like your humor
Hehe:hihi:

Has this just shown up since the new software?
 

·
Registered
Joined
·
1,198 Posts
Discussion Starter #8
Hehe:hihi:

Has this just shown up since the new software?
The humor or the carbon?

No, its always been there. Some times worse then others but it probably has to do with how I drive.
 

·
Registered
Joined
·
804 Posts
On my car it's more of a yellowish colore. Having an Alpine White car doesn't help and so does running no cats.
 

·
Registered
Joined
·
723 Posts
Another source may be from the battery. The battery is vented below the car using a tube. If you have etching on the back bumper which looks like little black dots that don't wash off, it's likely vapor which is vented from the battery, swirls around the back of the car and gets on the bumper.
 

·
Registered
Joined
·
1,198 Posts
Discussion Starter #11

·
Registered
Joined
·
162 Posts
Another source may be from the battery. The battery is vented below the car using a tube. If you have etching on the back bumper which looks like little black dots that don't wash off, it's likely vapor which is vented from the battery, swirls around the back of the car and gets on the bumper.
That crap is all over my bumper,i clayed the hell out of it,and barely removed it.
 

·
Registered
Joined
·
723 Posts
Really nothing you can do other than to install a sealed battery. Mine has it, but it's not noticeable enough for me to do something about it.
 

·
Registered
Joined
·
6,958 Posts
I have a ton of speckles from battery acid on the back of my RR beast. I have since dumped that antique lead and acid boat anchor of a battery for a lightweight dry cell.

If you care about the finish of your car dump that 60 lb monstrosity ASAP!

Dave
 

·
Registered
Joined
·
1,422 Posts
When I go to wash my car after a week or driving I see little black particles/dust all over the rear of the car. Looks like it might actually be stuff from the exhaust. Anyone else get this?
I think it's road tar that you can also find on the wheels. Generally, you find it most on the top of the rear bumper. I find that claying the car is the only diy solution to remove it.
 

·
Registered
Joined
·
543 Posts
my car had the speckles on the rear bumper when I bought it, but I never thought much about it until I read a post a while back about the battery acid venting onto the bumper. That's when it hit me that the spots were not chips but acid etching:eek:. Optima 34R installed the next day. I would recommend that everyone on the board keep a close eye on the vent tube and rear bumper for etching.
 

·
Registered
Joined
·
1,198 Posts
Discussion Starter #17
The material I am referring to is very easy to wash off. Comes off with just the hose.
 

·
Registered
Joined
·
587 Posts
even my car gets way dirtier in the back.

i think it's a comination of the dirt etc on the road getting sucked up from under the car and the exhaust.
 

·
Registered
Joined
·
5,078 Posts
I get that after the car has been sitting for a while, nothing like a long drive to blow out the carbon soot.
 

·
Registered
Joined
·
1,980 Posts
After working on my car this morning I noticed some etching on the rear bumper. I'm going to have to swap out the battery soon, so I guess I will be looking at the Optima.
 
1 - 20 of 23 Posts
Top