[HawkeyeG80]

I thoroughly detailed my car for the first time since getting it in January (I’ve washed it but nothing too in depth as the weather has not been great up to now). I noticed on both passenger and driver sides, the fin of the diffuser furthest to the outside appears to have lost a lot of its luster/shine on the side of the fin closest to the exhaust. I’m wondering if anyone else has had this issue? I’m guessing it may be from the heat of the exhaust tips? I tried everything to “scrub” it clean but no luck. Picture for reference

[mattssi]

Damn, that's rough. I don't think scrubbing it will help at all - probably the opposite. It's just ABS plastic. You may be able to salvage it w/ some polishing...

I'd be ticked if that happened though. Warranty issue even unless it was made worse by your attempts at fixing.

[HawkeyeG80]

Originally Posted by mattssi

Damn, that's rough. I don't think scrubbing it will help at all - probably the opposite. It's just ABS plastic. You may be able to salvage it w/ some polishing...

I'd be ticked if that happened though. Warranty issue even unless it was made worse by your attempts at fixing.

Didn’t scrub hard since I didn’t want to mare it and make it any worse. Might have to stop by the dealer and have them take a look. I just went at it with a few different shampoos and a microfiber cloth.

[biggripper]

I’m guessing the only way to restore that is to pop it off and try polishing. Difficult part would be finding a way to stabilize the diffuser so you can put a polisher on it.

[biggripper]

What I really want to know is if anyone who opted for the CF diffuser has experienced any discoloration issues. I also wonder if a different tip design like a CF tip might transmit less heat.

[chicagofan00]

Nothing like that on my CF diffuser.

I’d definitely swing by the dealership and see if they are willing to swap out under warranty.

[kgelfen360]

Where do you live? Is this from winter road treatment?

[HawkeyeG80]

Originally Posted by kgelfen360

Where do you live? Is this from winter road treatment?

Midwest, so yes we have road treatments. But there are no other spots on the car that have this issue, even the other side of the same fin is fine. Also shouldn’t the paint on a $90k car be able to withstand road treatment?

[Forzanerazzurri]

Originally Posted by HawkeyeG80

Midwest, so yes we have road treatments. But there are no other spots on the car that have this issue, even the other side of the same fin is fine. Also shouldn’t the paint on a $90k car be able to withstand road treatment?

Did the salt get baked on or something? So odd

[mattssi]

Originally Posted by HawkeyeG80

Midwest, so yes we have road treatments. But there are no other spots on the car that have this issue, even the other side of the same fin is fine. Also shouldn’t the paint on a $90k car be able to withstand road treatment?

It's not even painted which is the thing. It's just black plastic. Hopefully get a warranty swap or do what I did and swap out for the CF diffuser. No issues there and won't scratch and swirl (at least noticeably) like that gloss black one.

[bri1042]

This made me go check my rear diffuser. No visible issues at almost 27 months of Pacific Northwest driving. I would certainly try to get a warranty resolution for it.

[HawkeyeG80]

Originally Posted by mattssi

It's not even painted which is the thing. It's just black plastic. Hopefully get a warranty swap or do what I did and swap out for the CF diffuser. No issues there and won't scratch and swirl (at least noticeably) like that gloss black one.

I didn’t realize it was straight plastic, figured it had some paint but guess that makes way more sense since it’s not color matched for the G8x’s - ie why would they bother painting it black and not just color matching if it was actually painted. Could have come to that conclusion if I had thought a little harder haha

[skyline408]

Originally Posted by HawkeyeG80

I didn’t realize it was straight plastic, figured it had some paint but guess that makes way more sense since it’s not color matched for the G8x’s - ie why would they bother painting it black and not just color matching if it was actually painted. Could have come to that conclusion if I had thought a little harder haha

It's actually painted black. I've removed both my front bumper black corner pieces as well as the rear diffuser. It's painted black not black plastic. It's obvious when you look at the back of the pieces and you'll see the overspray paint.

Also, if you look at BMW parts description, they specifically mention (painted)

[jmg]

Looks like oxidation. Since it's painted, you can treat it just like any other paint correction. Some rubbing compound and polish, starting with the most mild and gentle then working your way up until it removes just enough oxidation to make it shine. Then making sure you wax every once and awhile to prevent it from happening again.

[mattssi]

Originally Posted by skyline408

It's actually painted black. I've removed both my front bumper black corner pieces as well as the rear diffuser. It's painted black not black plastic. It's obvious when you look at the back of the pieces and you'll see the overspray paint.

Also, if you look at BMW parts description, they specifically mention (painted)

Damn. Learn something every day.