I resisted making this post, but after seeing these ads for the 8th time today, I had to ask.
The two I remember are this:
1) the Cadillac's have a system that 'dries out' the brakes when it's raining
Uh.. aren't operating brake temps above 212* f?
2) Ferrari based their suspension design off the new Cadillac
.............?
Not all water that his brake rotors streams instantly. Say you're driving down the interstate, three hours or so, if it's raining and you don't ever touch your brakes, those rotors will get coated with water.
Also, with the way most cadillac drivers are, those brakes will never see 155°
As fat as the suspension, I'm pretty sure that was developed by another company, and it just made it to the cadillac before the 458.
Sounds like a good way to use up brake pads to me. I'm sure replacements are cheap.
That Ferrari uses magnetorheological dampers in its supsension which were originally developed by Delphi when it was still owned by GM. I think one of the special edition Vettes (Z06 or ZR1 or something) used them before Cadillac put them on the CTS V, but I'm not positive. The dampers contain a fluid with a high iron content. By applying a magnetic field to the fluid you can change it's viscosity. Using this fluid in a damper in a suspension system, you can tune the damper to give a soft ride for cruising and then change it incredibly quickly to a stiff ride for hard cornering. Here's a wikipedia link that should help you learn more about them.
Bob
Ze Germans had auto-dry brakes years ago.
I thought brake calipers were designed to always have the pad in very slight contact with the rotors in order to keep the system warm. As we know, cold brake pads can be very dangerous.
Perhaps this was an assumption I always had that was not based on fact.
They were first used on the 50th anniversary Corvette, Ferrari licenses them.
Schmidlap wrote: That Ferrari uses magnetorheological dampers in its supsension which were originally developed by Delphi when it was still owned by GM. I think one of the special edition Vettes (Z06 or ZR1 or something) used them before Cadillac put them on the CTS V, but I'm not positive. The dampers contain a fluid with a high iron content. By applying a magnetic field to the fluid you can change it's viscosity. Using this fluid in a damper in a suspension system, you can tune the damper to give a soft ride for cruising and then change it incredibly quickly to a stiff ride for hard cornering. Here's a wikipedia link that should help you learn more about them. Bob
I'm with Taiden on this one, I thought all front disk brakes since the 70's did this without a bunch of sensors and pumps. Just a small amount of drag to keep a layer of water from building up between pad and rotor.
As a side note, I'm sure it can't be just me that most higher end car commericals are now all about how many safety features they can pack into an overweight car. So much for performance and luxury.
In reply to Taiden and GhiaMonster:
Nope, brake calipers are designed to maintain a slight air gap between the pads and rotors. Here's how it works: the caliper pistons are sealed to their bores by a "square-cut" seal. when the brakes are applied, the pistons move toward the rotor, and the seal distorts. when the brakes are released, the seal pulls the pistons back as they return to their free shape. if the caliper is a sliding type rather than an opposed piston type, the caliper centers itself over the rotor as the suspension bounces up and down while the car is driven. in the pic below, the piston seal is the square cross-section next to the dust seal.
anyway, the "auto-dry" feature uses the pump in the stability control system to apply about 30psi to the calipers, which squeeges the water off the surface, it does not get them hot enough to evaporate the water.
I preferred the ads with Kate Walsh.
The ones playing Zeppelin were more confounding for me.
Like my old school 88 y/o dad would say... 'that's just more E36 M3 to go wrong, waddya want that for'
i've never had a problem with brakes not working in heavy rains- in fact, it's probably a good thing to have a little less initial braking force when the roads are wet.
i wonder how much it affects the overall fuel economy to have the brakes applied ever so gently from time to time like that? even a quarter of a mile per gallon would seem to be a concern to the automakers that need to meet those stupid CAFE regulations.
In reply to novaderrik:
iirc it applies once every four minutes when the windshield wipers are on. definitely less than 0.1 mpg hit or, as you said, it would be a concern for CAFE.
Just more snake oil for Cadillac to sell to ignorant consumers. Let's say there really is an issue with wet brake rotors (I for one call foul on this one). So, you hit the brakes and this dastardly film of water causes slip. I'm pretty sure with 4 different tires, 8 different brake pads, 4 different contact patches the coefficient of friction would be different. This would cause one brake to lock up before the other three. When this happens ABS steps in and all is well with the world.
But, this auto-dry system has a module. This module is expensive. This expensive module is a cash cow 2 months after the warranty is out. "Sir, your auto-bs module has malfunctioned. This is part of the braking system and is safety-related. If you decline repairs we'll deem the car unsafe and you will have to have it towed from the dealership. Oh, you'll authorize the repairs? Great. We'll have that done tomorrow. Oh, no we don't usually give reach-arounds here, we just stick it to you and make you like it."
Yeah because stability control modules that have been out for decades now fail all the time. 
Have you seen the new Cadillac's??
When they can't sell them on looks or styling, they need to come up with something to advertise...
Hocrest wrote: Have you seen the new Cadillac's?? When they can't sell them on looks or styling, they need to come up with something to advertise...
Thats the first time Ive ever heard anything bad said about the new cadilacs since I saw the Matrix.
Joey
In reply to DrBoost:
dude, you're all riled up over nothing on this one. go back and re-read my post. the auto-dry applications are done by the stability control module. also, wet rotors are less effective, not more effective, so the issue being addressed by auto-dry is the issue of less effective braking, ie longer stopping distance.
DrBoost wrote: Just more snake oil for Cadillac to sell to ignorant consumers. Let's say there really is an issue with wet brake rotors (I for one call foul on this one).
Drive my Swift GT in heavy rain. You have NO brakes for the first few hundred feet. All my cars have the problem, but not nearly as bad. Your cars must be special.
Hocrest wrote: Have you seen the new Cadillac's?? When they can't sell them on looks or styling, they need to come up with something to advertise...
I have. They are spectacular cars, beat up on their rivals on the track, look distinctive(as opposed to the copycat lumps sold by others) and are built pretty damn well.
AngryCorvair wrote: In reply to DrBoost: dude, you're all riled up over nothing on this one. go back and re-read my post. the auto-dry applications are done by the stability control module. also, wet rotors are less effective, not more effective, so the issue being addressed by auto-dry is the issue of less effective braking, ie longer stopping distance.
They'll come up with another module just for that. Then they'll charge you for it. I still say this is snake oil. I've NEVER felt brakes slip due to wet rotors, NEVER. And, again. IF there is an issue, ABS will clear it up after the first application.
I've never had a car brake any differently in the rain except for tire slip. Shrug.
I do know that after a good dunking in a creek/puddle my 4x4's brakes don't work that well at first. At least until the pads get the water off the rotors.
thatsnowinnebago wrote: I do know that after a good dunking in a creek/puddle my 4x4's brakes don't work that well at first. At least until the pads get the water off the rotors.
Dunking in a creek is different than a rainy road. And, does said 4X4 have drums in the rear? I've crossed many streams and creeks. You always do a light brake application to get the water out of the drums but I've never felt a difference with a disc-braked 4-by.
It's another thing the marketing people push. It's the same reason you have 19-way power adjustable seats in a BMW, because your neighbor only has 18-way.
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