Instead of washing my car (2017 XE), I decided to use Meguiar's Quick Detailer, which I have used many times before. I was amazed that the whole car had a film of an oily black substance on it. It was not noticeable on the paint, it just looked like it was dusty, but it sure showed on the rag. It even came off on my pant legs from leaning up against the car. I had previously noticed that there was a lot of this substance on my wheels and every time I wiped them off a few days later, there was more. The car is new, only 3 months old, so I don't have a lot of previous experience with it. I just know I had not had this happen on my previous car and we only have the one car so I can't compare. Logically, it was not from the environment because I had it in the same garage, drove it on the same roads, went to the same places, etc. I don't think it is smoke from the CA wild fires. Haven't been on newly paved roads and it has not even been parked outdoors much. The car has 1700 miles and it had been about a month since the last cleaning.
Could it be the brake pads? I don't know if they are prone to a lot of dust or if that dust could have an oily feel to it. However, I have not been hard on the brakes at all and I wouldn't think brake dust could get all over the whole car, top to bottom.
Any possibilities?

 

Is it the whole car or more around the tail? The XE shape (and I recall [or am I making this up?] the aerodynamics) results in air pushing it from the back, whatever it is it means that the back of the car gets really dirty very fast, especially the rear face of it, bumper etc. But otherwise our XE has never had anything similar to that. I had a lot of iron on my XKR once, which went pink when I sprayed it.

 

My first thoughts were brake dust or road grime. My wife's car is white and there is almost always a noticeable black sheen after she drives it for several days, particularly in the summer months.

 

OE Jaguar brake pads are notorious for creating a fine black dust but this usually only builds up on the wheels. It could possibly spread along the horizontal sides but is unlikely to reach the upper horizontal surfaces. My thoughts are it's environmental or emission from some other vehicle you have followed.

Graham

 

I have a 35t and it is remarkably free of brake dust, compared to some of my past cars.
An MB I owned coated the wheels heavily, but I don't remember it as oily or getting on the bodywork.

Hope you find the answer.

 

I have not noticed any real brake dust buildup on our rims -- at least nothing that I would call excessive.

 

We don't have a brake dust issue with our 2017 XE 35t R-Sport RWD. I wouldn't be surprised if they finally changed the pad compound to alleviate that.