Simple stock brake pad question

[Ulysses]

I just had my car teched for a 2 day event and the tech said that the rear pads were at 25% and the fronts were at 50%. I said "huh?". His method is to compare the lining to the backing. If the lining is the same width as the backing, then it is at 25%. Is this an accurate way of telling how much life is left on the pads? I checked it and the lining on the rears is about 1.25x the width of the backing and the fronts are about 2x the width of the backing. Seems to me, since the brakes are heavily biased to the fronts, that the fronts would be down more than the rears. There is about a quarter inch left of the slant that is cut into the pad on the rears. The pads all around are the ones that came with the car when I bought it new.

 

[GTS Dean]

Hmmm...

As a 'rule of thumb,' I guess that's not a bad measure, but I would probably take issue if challenged. Thin brake pads transfer heat more readily to the caliper pistons and brake fluid than thick ones do. Better to be safe than sorry.

 

[Ulysses]

I was afraid you were gonna say that! The work never ends! I guess I better get the jack stands out.

Thanks Dean.

 

[SAM Team]

Ulysses:

If it were me and I was going into a two day event and if I did nothing else....

1. Check all my brake lines for wear.
2. Check the rotors for cracks.
3. Drop all the brake fluid including the bad stuff that is in the calipers. Put some brand new high grade "something" in your beautiful car. Make it some of the real expensive stuff.
4. Replace the brake pads all the way around and get the dust off the rotors and the wheels. When you get the used pads off compare with the new ones, then "you" can make a better decision next time. Remember once you get beyond the crack in the pad you are into the compound(glue)that holds the steel to the actual brake pad. It will not help you stop to much...Now add what Dean said to this equation.
5. Check them every time you go out and come back in, you will be surprised how quickly they can go away. It all depends upon the track.
6. Listen to what your car may be telling you while you are out there. Listen to how it is "rubbing you". Bobby Archer told me this one, good advise.
7. Make sure you take God along with you as your co-pilot, you never know when you might need Him!
8. Go get them and have some fun......

Now you can think about all the other stuff!!!

 

[Ulysses]

"1. Check all my brake lines for wear."

Replaced all lines with stainless last week. Check.

"2. Check the rotors for cracks."

No cracks (thank goodness). Check.

"3. Drop all the brake fluid including the bad stuff that is in the calipers. Put some brand new high grade "something" in your beautiful car. Make it some of the real expensive stuff."

Well...flushed out the old Motul 600 and refilled with new Motul 600. Then bled them 3 days straight. Will bleed again several times over after new pads installed. Not the priciest, but I am a beginner and won't be going too hard. It should hold up for my creampuff kind of driving. New Mobil 1 in the pan. New fluid in the clutch reservoir. Coolant looks clean and healthy. Check.

"4. Replace the brake pads all the way around and get the dust off the rotors and the wheels. When you get the used pads off compare with
the new ones, then "you" can make a better decision next time. Remember once you get beyond the crack in the pad you are into the
compound(glue)that holds the steel to the actual brake pad. It will not help you stop to much...Now add what Dean said to this equation.
5. Check them every time you go out and come back in, you will be surprised how quickly they can go away. It all depends upon the track.
6. Listen to what your car may be telling you while you are out there. Listen to how it is "rubbing you". Bobby Archer told me this one, good
advise.
7. Make sure you take God along with you as your co-pilot, you never know when you might need Him!""

Will do! Especially 5, 6, and 7 right after 4. Check.

"8. Go get them and have some fun......"

It's going to be a blast!!. Check.

 

[SAM Team]

Have a great time I envy you......remember smoother is better, be technical driver, ride with a guy who knows the track and do what he tells you....you will be 50% ahead of the pack!!!