service due light (front brakes)

Checking thicknesses, on my car and several other cars it always ends up needing a disc change every other pad change.
If you are at -2mm after only 45000km I would double check everything with a caliper, that is not normal.

Originally Posted by Markst

Checking thicknesses, on my car and several other cars it always ends up needing a disc change every other pad change.
If you are at -2mm after only 45000km I would double check everything with a caliper, that is not normal.

I live in an area with hills and mountains.. maybe this is why.. no issues with the calipers, etc - 100%. even rears are worn about 1mm on the outer side (i did not measure the rears, just decided to replace them as well)

Originally Posted by gsnake2000

yes, I saw your post in some other thread..

the bedding procedure - did you mean using the ISTA+? (do you know how to navigate to it?)

No. I was referring to the proper speed/braking to do when pads are first installed so the pads sit correctly on the rotors. It involves a series of fast slowdowns without fully stopping. Like 50mph down to 5mph done quickly. That sort of thing.


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Originally Posted by BabyUnicornTaco

No. I was referring to the proper speed/braking to do when pads are first installed so the pads sit correctly on the rotors. It involves a series of fast slowdowns without fully stopping. Like 50mph down to 5mph done quickly. That sort of thing.


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ok, got it.. yeah, i never done this before after replacing the brakes but will keep it in mind, thanks!

Had the same issue but with the rear brakes. That was 3000miles ago and they are still fine. I purchased the Akebono pads and Zimmerman rotors just to have ready on hand. I had the rotors cut last brake change so saved me about 140$. Bought everything from FCP euro and amazon

Originally Posted by sohor1

The manual for my 991.1 C2S calls for caliper bolt replacement. For street use it's fine to re-use them a few times. If you're heading to the track, replace them or install studs into the hub. Most manufacturers do not require the bolts to be replaced, it's a money grab hiding behind a torque value/bolt stretch excuse. They're not going to back out.


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Ummm. I respectfully disagree. It's entirely possible that is the reason they use stretch bolts (money grab with little value added to user), however......
DON'T re-use stretch bolts.... EVER!
I had an O2J drop down to the subframe and rip the motor mounts apart on a mk4 VW GTI. I was going down the Jersey turnpike (at a fairly excessive speed). It could have been worse and it gave me a reason to swap in an O2M 6 speed and raxles. That's car had gone through 3 transmissions with the PO. It was an expensive lesson to learn. The trans mount bolts were stretch bolts and the P.O. had re-used them. I had the car for a week when this happened. Inspected to find the threads were not damaged. If it had been a new bolt and torqued properly, it would have ripped the aluminum threads out with it.
I've also (20 years ago) re-used the stretch bolts that bolt the pressure plate to the crank on an O2O. Let me tell you how much fun it was drilling those out of the crank shaft in a mk2 Jetta.
You can take or leave my advice and either way, I'll tip my hat and walk away. But is it ever worth that kind of trouble....? Even if you luck out a few times, it's not worth it to find out. IMO. To each, their own...

FYI, I just did fronts and tears pads and rotors on my diesel. Used hella rotors and akebono pads and love em. Tried to find textar epads but according to textar , they don't make them for the rear. Akebono s are almost as good as OE with much less dust.

Originally Posted by Diesel spectre

Ummm. I respectfully disagree. It's entirely possible that is the reason they use stretch bolts (money grab with little value added to user), however......
DON'T re-use stretch bolts.... EVER!
I had an O2J drop down to the subframe and rip the motor mounts apart on a mk4 VW GTI. I was going down the Jersey turnpike (at a fairly excessive speed). It could have been worse and it gave me a reason to swap in an O2M 6 speed and raxles. That's car had gone through 3 transmissions with the PO. It was an expensive lesson to learn. The trans mount bolts were stretch bolts and the P.O. had re-used them. I had the car for a week when this happened. Inspected to find the threads were not damaged. If it had been a new bolt and torqued properly, it would have ripped the aluminum threads out with it.
I've also (20 years ago) re-used the stretch bolts that bolt the pressure plate to the crank on an O2O. Let me tell you how much fun it was drilling those out of the crank shaft in a mk2 Jetta.
You can take or leave my advice and either way, I'll tip my hat and walk away. But is it ever worth that kind of trouble....? Even if you luck out a few times, it's not worth it to find out. IMO. To each, their own...

i agree.. $40 for 8 bolts is not a big expense.. but I figured most people (including services) don't change them..

Originally Posted by gsnake2000

I got the "service due" light message and it was about the front brakes. I looked at the pads and they still have about 3-4 mm (1/8 or a bit more) of thickness. I am wondering if this is a 'preventive' call (the car has 44500 km on it) or this is the brake pad sensor triggered. What I am saying is - do I rush and get the parts now or there is still time to do it in the next 1000 km? Or I simply reset the service due and wait for the sensor to tell me it is time?

My break service icon came on and when I took it to dealer they said it was the front break sensor , nothing was wrong with the breaks ,pads were good, I only had a bad break wear sensor,

Originally Posted by giant head

My break service icon came on and when I took it to dealer they said it was the front break sensor , nothing was wrong with the breaks ,pads were good, I only had a bad break wear sensor,

Did they explain why the sensor failed? It’s takes wear to make it pop up.


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Faulty sensor sends message to computer reporting breaks pads needs service. If you can see that you have plenty of pad material left on your pads, the service fault light is coming a faulty sensor.

Originally Posted by giant head

Faulty sensor sends message to computer reporting breaks pads needs service. If you can see that you have plenty of pad material left on your pads, the service fault light is coming a faulty sensor.

I think it depends on how many mm you have left. The sensor causes the code before they have to be replaced. It’s a warning. Not a rush and go get it done warning.


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I don't know if this is a universal statement, but stretch bolts (aka torque to yield bolts) have a specification that includes initial torque and then an added rotation of X degrees. So, when I don't see an added degrees in the spec, I assume the bolt is not a stretch bolt. Now, the bolt may have some fancy integrated locking feature that is one time use only, but that's a different thing.

All fasteners in tension - not compression or shear - stretch. Yield means that the stress goes into the plastic region of the stress-strain curve, plastic where the strain is not recovered. If the fastener does not yield then it has stayed in the elastic region and can be reused as far as metallurgy goes. Procedure is another issue. To be clear, stress units are force per area, lbf/in^2 in English. Strain units are change in length per length.

In other words..."stretch bolts" or "torque to yield bolts" are bolts that stretch *beyond* their ability to go back to their original length when removed.

TTY go into plastic region. All clamping bolts / fasteners stretch a bit, not necessarily yielding.

Originally Posted by twh

In other words..."stretch bolts" or "torque to yield bolts" are bolts that stretch *beyond* their ability to go back to their original length when removed.

Yes. To avoid engineering vernacular (no offense meant, just trying to keep it simple for posterity), think of it like a paper clip or a spring. If you bend a paper clip slightly, it will bend back. A little too far or back and forth a few times and it will snap. Think of the old suspension leaf springs in the days before independent suspension. The metal spring pack is just flat bar bound together. As you encounter a bump, the flat bar "deflects" (bends) a bit and goes right back to where it was. It can do this for hundreds of thousands of miles. Now imagine you put a small crease in the top leaf on a metal break and re-installed it. What would happen whenever you hit the next bump? Wouldn't be good. The spring would just bend at that point and no longer spread that deflection over the whole span between front and rear mounts.
Think of torque to yield fasteners as being installed to spec and then "bent" or "creased". Once they are, they'll hold what they're supposed to at the engineered spec. Until, they're removed. You can't re-use (un bend then re-bend) them because they can not be expected to hold to the same (engineered) specs. It only takes a few bends of that paper clip to completely fail.
So for safety's sake, you can (probably) re-use TTY to hold together paper, but not transmissions, pressure plates or brakes.

got all pads and rotors replaced yesterday. took a while mostly because I cleaned up the spots for the pads to slide nicely with the brush/sandpaper.
the pads had about 2-3mm of the material on them. so, the conclusion is after the service light there is about at least 1000 km or more before the pads would wear out completely.. maybe even more.
for the caliper slides - it is 7mm not 9 mm hex.

Originally Posted by gsnake2000

for the caliper slides - it is 7mm not 9 mm hex.

Bummer. Sorry...



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Originally Posted by deroy

Bummer. Sorry...



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luckily I had one no biggie