squishy brakes, new rotors, pads, and rear calipers
#11
10-20-2014, 04:26 PM
I had the shop test the entire brake system for any weakness and they found nothing. So I went back to the beginning and checked the front pads. (Rear pads have less than 10,000 miles on them). I sanded them down to see if I could get a different feel from them and I did. The truck immediately after was worse but after a couple laps down the block it improved. Sad because the front rotors and pads only have 25,000 miles on them.
#12
10-21-2014, 10:37 AM
Not sure if you're aware, but brakes to need to be broke in. I've found that some types of pads tend to break in better than others - most likely due to pad quality. I usually use ACDelco pads, and machine the rotors whenever possible. Here is a quick video demonstrating the procedure: 2 MINUTE TECH - Burnish In New Brake Pads The Right Way | PowerBlockTV Network - Video
Personally, I don't care for how they do it. Once you make a fast stop like that, the rotors have a great opportunity to warp right around the wheel studs and can cause a pulsation - especially on new rotors. Here's my theory, when you have rotors machined, you take an already heat treated rotor that's been through many, many heat cycles. That kind of tempers the metal and makes them less likely to warp. I'm not saying it can't happen, like a high spot created by a dragging pad, but I'm saying that warpage due to heat is not as likely to happen.
So what I do, is I get out there on good flat stretch of road that you can drive for a while without stopping, and hit the brakes going from 50-60 down to about 30MPH in a matter of a couple of seconds. Don't lock the brakes, but only apply them for a short few seconds to get the rotors hot. This also brakes in the pads. Then try your hardest to drive for at least a 1/4 mile to let he moving air cool the rotors. Then repeat.
I've found that if you are really gentle on the brakes immediately after installing them, you tend to glaze them really quickly. The glaze looks like the rotors got shiny like a mirror, and the pads get a glazed look like a doughnut looks. That's fixed by machining the rotors and sanding the pads.
Hope this helps.
Personally, I don't care for how they do it. Once you make a fast stop like that, the rotors have a great opportunity to warp right around the wheel studs and can cause a pulsation - especially on new rotors. Here's my theory, when you have rotors machined, you take an already heat treated rotor that's been through many, many heat cycles. That kind of tempers the metal and makes them less likely to warp. I'm not saying it can't happen, like a high spot created by a dragging pad, but I'm saying that warpage due to heat is not as likely to happen.
So what I do, is I get out there on good flat stretch of road that you can drive for a while without stopping, and hit the brakes going from 50-60 down to about 30MPH in a matter of a couple of seconds. Don't lock the brakes, but only apply them for a short few seconds to get the rotors hot. This also brakes in the pads. Then try your hardest to drive for at least a 1/4 mile to let he moving air cool the rotors. Then repeat.
I've found that if you are really gentle on the brakes immediately after installing them, you tend to glaze them really quickly. The glaze looks like the rotors got shiny like a mirror, and the pads get a glazed look like a doughnut looks. That's fixed by machining the rotors and sanding the pads.
Hope this helps.
Thread
Thread Starter
Forum
Replies
Last Post
scott_z71
Chevy Silverado/ GMC Sierra Forum
14
10-10-2019 07:26 PM