Vetch

I recently bought a '14 Cayenne to replace my '13 Cayenne which was totaled a few months ago. Both performed well in every respect. In fact, I probably couldn't tell them apart if driving them blind folded. (ha!)

But I'm noticing increased stopping distances now on long and on short drives. Pedal travel feels fine but I did a flush anyhow. No results (none expected really) from that. The pads have good thickness and the rotors look fine.

Any ideas what would cause increased stopping distance?

Kdavis61

deilenberger

Do we know what pads are in the '14? Factory or aftermarket? Some pads sacrifice stopping power for lower brake dust. Not a good tradeoff IMHO. And are the two vehicles comparable in brake configuration? There is a big difference between base, S, GTS and Turbo brakes.

RAudi Driver

Im going with brake pads must be different.

Vetch

I dont think it's the pads because for the first three to four weeks, I thought the braking performance was excellent (just like the '13 model I had). It's just been during the last week or so that I've noticed a change in the amount of effort I use to stop the car.

And they are definitely dusting like OEM pads.

deilenberger

Vetch - I think we're still missing some info - like what model Cayenne you're experiencing this problem with.

Vetch

Both are S models.

LexVan

You say the pads look fine, but what abot the inner pad that you can't easily see??

Vetch

Good point but I had the wheels off last weekend to flush the brake lines. The inside pads look as good as the outside pads.

deilenberger

OK. So you've left us with an unsolvable mystery. I think you'll have to get used to it, or take out a pad and figure out who made them. Could be contaminated pads - run through any deep water recently?

Gptoyz

Assuming the options in the car are equal - in other words the relative weight of the car is equal it would come down to the following possibilities:
- tire choice - it's the only performance/safety feature that touches the ground. The compound of the tire determines how fast you can accelerate, brake and turn
- alignment - assuming the tires are exactly the same; 2 different alignments will again determine how the car brakes, turns and accelerates and uses up tire life.
- brake pad compound
- suspension; if the suspension is blown or not performing to par then the car won't transfer weight optimally.

Btw maximum braking occurs at the moment just before the abs kicks in. If your abs is over active and engaging early, you could have a pad difference problem or possibly air in the system.

Vetch

I'm confident that this is related to only to the pads. The braking performance I was referring to is "around town with the kids in the car"... just gentle stops.

I've not driven through any deep water but it has rained like I've never seen here lately. I read somewhere else that it may help to sand the rotors and pads with 60 grit sand paper to remove any surface contaminants and glazing. I don't see glazing on the rotors though and I think it was Abraham Lincoln who once said "Don't believe everything you read on the internet."

Smitten

Have you looked at master cylinder issues yet? As a master cylinder just begins to fail, there is an almost unnoticeable softening of the pedal but a very noticeable drop in braking performance. It is so gradual that most drivers don't notice the change in pedal feel until much later. Over time, as the master cylinder degrades further, the pedal gets softer/spongier and eventually can be pushed slowly to the floor.

hotrod2448

You might try re-bedding the brakes.
https://www.essexparts.com/support/learning-center--faq

When I got my CD they had replaced the pads and rotors as part of the CPO process. It took a while for them to bite the way they should. In the BMW world guys would go through this process a lot as the factory pads were bad about transferring material resulting in a pulsing in the pedal.

abiazis

Pads and maybe rotors are shot?