My beloved XKR went for some servicing the other day.
The car is a Dynamic R 2014 with 6000 miles.
Although I never drove the car on salty roads and rarely on rainy days,I noticed the rear subframe surface was rusty.
Any suggestion on how to address it?Brushing,painting and then waxing come to my mind.Good idea?What products would you use?

How it looks-rest is pristine.

 

In the Northern US, people spray Bar & Chain Oil on the undersides of their vehicles when the snow gets likely. Not only does it stop the surface from further rust, but the road grime that sticks to it is another layer of protection. When it gets thin in areas, another coat right over the top. All my dad's cars were totally rust-free, although you wouldn't vote it "best underside" at a show.

 

When I first went shopping for rust prevention treatment in New Zealand I was surprised to find that this is what they use here:

 

That looks similar to the level of surface rust on mine based in North East England although it has more than ten times the mileage of yours. The subframe is unsightly but it's not a problem for safety or MoT. Of greater concern to me has always been the corrosion on the exhaust system. I'd love to know where Jaguar find stainless steel that rusts!

I looked at the options and decided to wait until the suspension bushes need replacing as there's no way to get access to the entire subframe in situ and painting the bits that show would only impress anybody I happen run over. When the time comes for bush replacment, I'll drop the rear subframe, clean off the rust, prime and refinish it with something like Hammerite smooth.

Graham

 

I would clean every surface you can get at with various wire brushes, then paint with something tough like this & spray with a wax all the areas you can't get at to paint.

 

Fish oil! Having horrid thoughts of cod liver oil from my youth;-)
in all seriousness, I am looking forward to comments on this thread. In the year 2020 there must be a modern solution to this age old problem.

But I don’t want an oil spray. As good as the effects are, I detest the dripping mess. And it’s a dirt magnet.

 

Damn, mine has 44k on it and is a 2012. Absolutely zero rust anywhere. I guess I got lucky. Sub-frames and many major components are contracted out, usually to the lowest bidder and that definitely affects quality. Rusty stainless exhaust systems ? Anyone bought a cheap grill from the major big box stores and had rust appeared on it after less than a year? Off shore / low grade stainless will rusty. As far as prevention goes, the only way to stop the corrosion spread is to get the surface free from rust, chemically treat the areas and paint. I would not squirt oil all over the place and have that crap dripping on the driveway, garage floor and on you while working on the car.

 

WD-40... made by rocket scientist for their rockets. Should be good for street rockets. 🙂

Works good and is is easy to clean off when you have time to permanently address the rust and corrosion. Or, just keep re-treating the rusty spots as needed.

 

Pictures do not look rusty to me, try wiping it with an oily rag first. If you drive in winter on salted roads, I recommend using oil spray (don't use anything organic, like Fish Oil). Downside is that it will be harder to diagnose future oil leaks and the grease will accumulate dirt. If you only drive in the summer, it is not worthwhile to do it.

The way you drive your car, your best approach is to DO NOTHING. Any cure here is worse than disease.

 

I used this stuff on the suspension arms of my X100 to great effect as lasted for years

https://www.por15.com/POR-15-FAQS_ep_61.html

 

Clean it up with a wire brush then coat it with POR-15 to stop the rust.
Then spray it once a year with WoolWax. If you don't have an air compressor or don't want to buy the spray gun you can brush it on but it's easier to spray.

Chainsaw bar oil, WD-40, and fish oil are all good suggestions but WoolWax outlasts them. You might hear a suggestion for Fluid Film but Wool Wax is thicker, lasts longer, and doesn't have the Fluid Film smell.
I sprayed WoolWax on my Sequoia back in November and even after running it through the car wash every week this winter it's still there.

 

These under-body oil treatments do NOT drip or splatter all over. That would render them all useless. They stick where they are placed and protect the steel substrate for a very long time. They are also easy to remove if required with a quick hot water with Dawn pressure wash.

 

Thank you for all the advices!
At the garage-a Jag specialist,not an official dealer,they suggested to brush it and then wax it but it makes sense to me to stop the rust-even if little-with some POR15?-and then applying wax.
I am surprised by the presence of corrosion considering the mileage of the car.
The car is now in sunny Spain but if there is sun there is also periods of high humidity here-so I better doing something about it I guess...

 

Paint it with black rust paint. It'll look better and last longer.

 

There is a dark reality, these types of cars (Jag, BMW,Audi, Merc,etc) are not designed in the slightest for longevity.
When I was in the auto industry, life after 10 years required a lot of extra design and planing- only companies like Honda and Toyota were committed to it. You would not believe how many extra steps and creativity it took to make a coil spring last more than 10 years without squeaking. For one we had to have a test facility to recreate 10 years of use.

I have not seen a single step taken on the Jaguar. Understandably- few if any bought an XK to keep beyond 3-5 years, same of every BMW, Audi, Merc. Now the Japanese, just the opposite.

This is my 28 year old baby that was rear-ended this weekend and what you see is the car compressed by 15% 40% in rear. I never had to go under it, never washed the underside of any salt- look at how pristine the steel is behind the factory undercoating. The under coating only failed where it was bent past a certain degree. Look how thick the undercoating is. Every bit of that is original from how it was make in Japan. Where permanence is central to the culture.



Look at the washers, aluminum with buna-N on both sides to prevent galvanic corrosion and dampening vibrations. And they are different sizes machined.

 

Heck forget the rust that clearly shows really crappy metallurgy (i.e. not hardened) look at the exposed wiring- there is zero consideration given to long term global use.
I cant believe someone at JLR actually thinks electrical tape lasts a long time.
Maybe that steel is being used as an anode.

 

Temporary thread hijack:
Q&C, what car was this? Sorry for your loss...

 

Thanks man, a Toyota / Lexus.
Kid on a phone watching a video plowed in at 50 miles an hour to a stationary car

Point of relevance to the thread being- nowadays, loser on a phone will get you before rust does.

 

Makes me want to go get a TR4 so nobody has a chance to crash into me!

 

Can only agree with you Q and C:I am disappointed by the level of rust and the wiring left exposed.
Wonder what Jag would say about that...