The brake booster in my 2008 Stype has failed. Yes certain that is the problem, I put in a new vacuum check valve and rubber grommet the check valve inserts into. The rebuilder had no parts to rebuild anything that new. Cardone has the item as discontinued, and it was $780.00 Canadian for a rebuilt unit. Nothing on the Web and my only option is a new unit from Jag at $1039.00. I can't believe that this is truly unique part to that car. Is there a crossover part number to a Ford part, or is it used on any other model. I took the part out of the car, not a big job and the Jag part will be here on Friday, but surely it can't be that unique.

 

So no reply to my question about the booster, so the JAG OEM part should be here on Friday. I got the old booster out, not a terrible job, only took about 45 minutes.
The booster has rust in the strangest place which probably accounts for the failure to hold a vacuum. I have attached some pictures. I have looked all around on the inside above the pedals, and the firewall side and can see no indication of water penetration and yet the photos show the condition of the booster. Strange.
Any insights appreciated. Rust under the rubber boot.
Rust inside the brake rod shaft. There is no sign of moisture anywhere.

 

That's the side that breathes when you hit the brakes. Moisture in the cabin and temp / pressure difference through the orifice could cause local condensation which leads to rust.

 

Thank you, that makes a little more sense.