Brake Pad Thickness
 

At what thickness would you replace your brake pads?

The dealership told my wife that she'd need her brakes done soon because their at 12mm and that the min pad thickness was 10mm...

Isn't the min pad thickness usually 5mm or less?

I'd replace them when the brake pad wear sensor triggers. Otherwise, you'll be subject to the emotional upsell of replacing pads prematurely.

^This. Either there's enough pad material or there isn't. I don't believe in early brake pad changes. I'll bet she runs another 10-15k km before the indicator goes on.

New pads are in the 10 - 12mm range so I don't know what the dealership is saying. I think you normally replace around 2 - 3 mm. Steve

Agreed, just typical dealership crap, trying to sell her something she doesn't need. The same day, they also tried to convince her that the Q5 needed a $250 fuel injector cleaning service at 55,000kms. She declined that too!

I assured her that there's a sensor that will tell her when the brake pads actually need to be replaced.

Dealerships...

Good for her. Women are especially vulnerable to the upsell when it comes to their cars.
I notice you have the 3.2 Q. I'm not trying to sell you...LOL but I've used this regularly to keep the Carbon-build-up monster at bay.

http://audiusaparts.com/pages/index....0&pageid=13643

People get scared by technical words like "millimeters". Last time I heard a pitch like that--and I've heard if often--my reply was something like:

"The new pads are 12mm, I've put 30,000 miles on these and I have 5mm left. That means I get about 4,000 miles per mm and since I drive 5,000 miles per year I have three years left until I reach the factory minimum spec, which happens to be 1mm on these pads. Would you like to see the service manual or do you already own a copy?"

Needless to say I found a new inspection station the next year, a crook is a crook no matter how gently he steals from you.

They work as written in: Strict maintenance operations

Attachment 78630

That's the first I've heard of using "backer and damper plate" as part of the thickness measurement. Now why would Audi include non-wear components in their wear component measurement?

This procedure has been around for awhile
 

If you look at the pictures in spijun's attachment, it's really just a depth gauge like a tire wear reader they are sticking into the caliper area. It negates need to pull wheels to check pads, especially the inside one that can be tougher to see visually--that ease of quick service check is really the driver here. Then as long as you net out the standard backplate, any (small) shim/anti-rattle material if used on the given pad, and the depth of any access hole, the spec number is arbitrary--10mm in the case of that procedure. Assuming they are looking for something like 3mm of pad, then the other 7 are allocated to the other measured materials in that document. In the 2011-2012 Q5 Quick Reference Specification book I have saved as a mini service guide absent a manual, it specs it at 7mm min for the pad material, back plate and dampening sheet, both front and rear. That appears to be a direct measurement of the overall component thickness rather than through an access port. I expect the 3mm further delta is the access hole depth.

All kind of academic to me though since I just do it visually, with a close look twice a year w/ winter/summer tire changeovers.