Dirt staining INTO the paint - Warranty? Cleaning?

[Probity]

Good luck with Ford warranty relief on that, prepare for disappointment.

A couple questions - I'm assuming that bumper piece is plastic (not metal), correct? Also, before you bought it, how long had your Oxford White Mav been on the dealer's lot?

Had similar issue with my previous 2018 Oxford White F150 Scab. Plastic below the grill area. It was a 'birthday truck' (had been on a south LA lot for over a year before I bought it in new in 2019). The price ($16k below MSRP w/o any dealer adds) was too good to pass up even with the 'dirty' plastic I too couldn't get clean. I lived with it and my wallet thanked me.

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[mfergel]

Auto car wash chemicals?! Can't claim warranty on that...

Nope. As mentioned, this is dirt that is appearing after it rains. It's just runoff. No chemicals, no leaks, etc.

 

[mfergel]

Good luck with Ford warranty relief on that, prepare for disappointment.

A couple questions - I'm assuming that bumper piece is plastic (not metal), correct? Also, before you bought it, how long had your Oxford White Mav been on the dealer's lot?

Had similar issue with my previous 2018 Oxford White F150 Scab. Plastic below the grill area. It was a 'birthday truck' (had been on a south LA lot for over a year before I bought it in new in 2019). The price ($16k below MSRP w/o any dealer adds) was too good to pass up even with the 'dirty' plastic I too couldn't get clean. I lived with it and my wallet thanked me.

Yes, plastic bumper. This was brand new off rail car. Pre-ordered back when you had to wait six months, so it probably sat on the lot for a day or two at most.

 

[Escapologist]

I've had white cars before where it seemed like it was the rubbers and seals leaking black with the wet and striping the paint.

 

[HeyBales]

It's definitely dirt as I'll also have the dirt trails running down from other areas where the water runs off the vehicle (like at the door handles, gas tank lid, etc). The dirt is really coming from just everyday use. My driveway has a slight slant sideways, so when I park, any dirt from the grill, deck lid, etc tends to run to the drivers side when it rains. No cleaner or liquids draining. I use fairly decent cleaning supplies (Chemical Guys, Auto Geek, etc). I don't want to try anything caustic to try and remove it, but even using bug and tar remover doesn't seem to do anything as it is in the paint. My biggest concern is this is after two years and it's just going to keep getting worse, so I have a feeling at some point the bumper is going to need to be repainted.

Mine was after my 1st car wash, from door handles and mirror areas, couple other spots - never looked at bumper areas for it.
I did not wipe it down after washes - shoulder problems from bike accident just prior to getting truck.
Like manufacturing remains or material bleed off, the dark really stands out from the Cactus gray.
I like the idea it might be a soap interaction issue - I've been using a different car wash last several times - need to look closer if still there.

 

[mfergel]

Mine was after my 1st car wash, from door handles and mirror areas, couple other spots - never looked at bumper areas for it.
I did not wipe it down after washes - shoulder problems from bike accident just prior to getting truck.
Like manufacturing remains or material bleed off, the dark really stands out from the Cactus gray.
I like the idea it might be a soap interaction issue - I've been using a different car wash last several times - need to look closer if still there.

Yeah, you definitely understand issue then. It happens at the door, the mirror, back at the C-pillar (from water run off on the roof), etc. I have no issue with getting those areas clean and I'm using the exact same cleaning supplies, wash cycles, etc. I am NOT treating the front bumper any differently than the rest of the vehicle, so it's definitely something about the paint on the front bumper.

 

[commod0re]

Give it a good hand wash and then go over it with a clay bar. If you get all the dirt off and it turns out there are scratches too, buffing spray and a clean microfiber cloth should help immensely

 

[Chops]

Nope. As mentioned, this is dirt that is appearing after it rains. It's just runoff. No chemicals, no leaks, etc.

Rain borne chemicals? Canadian smoke? Chemtrails?
Aliens?

 

[Probity]

Yeah, you definitely understand issue then. It happens at the door, the mirror, back at the C-pillar (from water run off on the roof), etc. I have no issue with getting those areas clean and I'm using the exact same cleaning supplies, wash cycles, etc. I am NOT treating the front bumper any differently than the rest of the vehicle, so it's definitely something about the paint on the front bumper.

Yeah it's a common problem with painted plastic bumpers/trim panels/etc. More (most?) noticeable with white paint.

The plastic car bits are painted differently (and separately from) body panels, can have 'flex agents' (or something similar) in the paint itself, different thermal conductivity of plastic painted bits vs metal (a longer cure time for paint on plastics). A few random articles on this in general:
Why Bumpers Are Off-Shade From The Rest Of Your Car | New Old Cars
Clear Coat Failure or Water Spot Damage | Auto Geek Online Auto Detailing Forum (who knew there are 2 distinct types of bird droppings; learn something new every day...)
Auto Paint: Plastic Bumpers' Unique Sheen | ShunPoly

20 y.o. article but still valid today. What the paint guru Bobby G said in his paint clinic:
Paint Clinic | Autopia Forum-Auto Detailing & Car Care Discussion Forum

"Most modern cars use plastic bumper systems and fascias made of thermoplastic olefins (TPOs), polycarbonates, polyesters, polypropylene, polyurethanes, polyamides, or blends of these compounds. Often, glass fibers are added to provide more strength and structural rigidity. Plastics allow automotive engineers to have a lot of freedom in styling, building and placing components.

Plastic also lends itself to combining several complex parts into a single, integrated piece, such as a bumper cap or spoiler. From bumpers to door panels, plastics give car designers and engineers the freedom to create shapes and designs that otherwise would never be possible. With all of their benefits, plastic body parts do have limitations and drawbacks. One of the issues that I have discovered over the years is that painted plastic body parts are easily stained and dulled. To understand why, I researched the process of painting plastic bumpers and how it differs from painting metal body panels.

I have long known that it's necessary to add a "flex agent" to paint that will be applied to plastics. The flex agent allows the paint to move with the plastic part without cracking or delaminating. What I did not understand is how the flex agents work. It's very interesting, and it explains why painted plastic parts are so susceptible to staining and dulling.

Paint flex agents cause the cured paint to be more porous. In essence, the flex agent makes the paint foam, creating microscopic pockets. These pockets allow the paint to remain spongy and flexible. Most of the pockets are deep in the layers of paint, but some float to the surface. The flex agent also causes the paint to remain soft. Paint on TPO parts resists chips very well, but it will dent (small pock marks) from road stones.

The porosity and softness afforded by the flex agent create a couple of challenges. First, the paint does not resist stains as well as paint without a flex agent. Second, the flex agent paint cannot be buffed or polished with anything more than the finest polish, or the finish will be ruined. Buffing does not increase the gloss on this paint as it does on a hard paint finish; it smears it. I've seen a dozen or more cases of botched repair jobs, where an inexperienced painter used a buffer to blend paint, and put permanent buffer burns and smudges in the bumper cap. I've seen even more cases of car owners using a rubbing compound on their soft plastic bumper caps to remove bug stains. The paint dulls and never returns to full gloss. I have also noticed that etching from hard water and bird droppings is much worse on the painted plastic parts."

You can try this (I did )- it didn't work on my "porous paint stain" but with sufficient elbow-grease it did eventually remove my wax, clearcoat, paint, etc. Other than a re-paint, I don't think it's fixable with conventional detailing products.
The Best Way To Clean Painted Plastic Bumpers | ShunPoly

 

[mfergel]

Yeah it's a common problem with painted plastic bumpers/trim panels/etc. More (most?) noticeable with white paint.

The plastic car bits are painted differently (and separately from) body panels, can have 'flex agents' (or something similar) in the paint itself, different thermal conductivity of plastic painted bits vs metal (a longer cure time for paint on plastics). A few random articles on this in general:
Why Bumpers Are Off-Shade From The Rest Of Your Car | New Old Cars
Clear Coat Failure or Water Spot Damage | Auto Geek Online Auto Detailing Forum (who knew there are 2 distinct types of bird droppings; learn something new every day...)
Auto Paint: Plastic Bumpers' Unique Sheen | ShunPoly

You can try this (I did )- it didn't work on my "porous paint stain" but with sufficient elbow-grease it did eventually remove my wax, clearcoat, paint, etc. Other than a re-paint, I don't think it's fixable with conventional detailing products.
The Best Way To Clean Painted Plastic Bumpers | ShunPoly

Thanks. Yeah, knew about the flex additive and like you mention, I can notice a 'slight' color difference. I bet you're right in regards to some of those microscopic pockets being formed on the top and that's why it's holding onto the dirt and causing it to stain. It just sucks because I never had these issues with my other vehicles. This is the first. I do have a DA orbital polisher/pads/etc. and had buffed my Mustang completely. I suppose if I reach the point that I get ready to have the front bumper painted that I could just see if buffing it out (at a low speed to avoid the issue of smearing like you point out) removes the stain. I doubt it since there really isn't a lot of thickness to the paint. My other thought has been to wait and see what kind of aftermarket bumpers come out, but honestly, I've modded enough vehicles over the years that I'm at the "simple is best" point.

 

[h1k3rb]

...I've modded enough vehicles over the years that I'm at the "simple is best" point.

+1 to "simple is best".

Can't help but laugh at some of the customized vehicles I see driving around here in SC. Especially the 4x4 crowd! There's no available BLM land like out west so you have to drive quite a distance and pay to use an off-road vehicle park at about $25 a day - to beat the crap out of your ride. Some mods I've seen have to add up to tens of thousands of dollars, likely more than the original cost of the vehicle. As someone who's had a couple 4x4's , a Baja Bug and dual-sport motorcycles, I get the enjoyment of off-roading but unless you've got LOTS of money to burn I'm just not seeing it around here.

Anyway, I'm way past the point of wanting to stand out from the crowd with a vehicle (or anything else) that screams "Look at me!" and enjoy keeping a relatively low profile to more or less fade into the background. When all the dust settles nobody really cares what you're riding around in. Even your friends who tell you how cool it looks are likely really thinking either, "Inadequacy issues?" or "What a dork".

 

[Cherokee]

nor my 2025 EG Lariat.

Wassa EG Lariat ?

 

[Escapologist]

The other day I treated a stone chip rust spot on my Kia Rio, which is white. I guess it is in a spot where the airflow diverges, because there was quite a large area of faint orange stain in a quadrant below it. Some of it blowing back at highway speed, some of it dribbling down when standing etc.

Anyway, this morning to see what it did, I just took some household Comet with bleach powder cleaner, wet a cloth shook some on it, and the orange cleaned off real easy with light pressure. IDK how much paint you take off if you go hard at it, but didn't get much "chalk" on the cloth. So that worked pretty good for my issue, rinsed with plenty of water after of course.

 

[Maverick123]

Did you try LA's totally awesome cleaner that I recommended earlier in this thread? I'm pretty sure it'll work, and for $1.25 it's worth a try before breaking out the buffer and compound. It completely erased similar stains that were 10x worse on my white gutters with zero effort

Also this is a common problem on campers. RV stores sell a spray called black streak cleaner or something similar which probably does the same thing

 

[mfergel]

+1 to "simple is best".

Can't help but laugh at some of the customized vehicles I see driving around here in SC. Especially the 4x4 crowd! There's no available BLM land like out west so you have to drive quite a distance and pay to use an off-road vehicle park at about $25 a day - to beat the crap out of your ride. Some mods I've seen have to add up to tens of thousands of dollars, likely more than the original cost of the vehicle. As someone who's had a couple 4x4's , a Baja Bug and dual-sport motorcycles, I get the enjoyment of off-roading but unless you've got LOTS of money to burn I'm just not seeing it around here.

Anyway, I'm way past the point of wanting to stand out from the crowd with a vehicle (or anything else) that screams "Look at me!" and enjoy keeping a relatively low profile to more or less fade into the background. When all the dust settles nobody really cares what you're riding around in. Even your friends who tell you how cool it looks are likely really thinking either, "Inadequacy issues?" or "What a dork".

Yeah, I lowered mine and added the wheels, but that was partially because I'm a sports car guy and not a truck guy, so this at least gives me some middle ground. I'm like you. I have wanted to buy a dirt bike, but don't want to drive somewhere in order to use it. I sold my jet ski because I got tired of having to drive to use it. Now if I could find the time to work on my bug, that would be great (I don't know if I would do baja or hood ride). That will probably just get sold at some point BECAUSE I don't have lots of money to burn.

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