Vibration when braking

[Khughes6103]

Hey guys, I’m restoring this 04 Sierra that my father in law gave me. From the time I got it from him, there was a vibration/surging in the front end when braking. I assumed it was rotors and or pads. I replaced the front rotors and pads and found two cracked pads. I didn’t do the from brakes on the back because he said he had them done last time he had the brakes done. I’ve only done mine once on my 03. I went ahead and put shocks all the way around because it needed them. I’m planning on replacing the front coil springs because it has that classic nose dive towards the front drivers side. While I’m at it, are there any other suspension parts I should replace? It STILL has the vibration even after brakes and rotors.

 

[Khughes6103]

Forgot to mention, it’s a 2wd

 

[Mooseman]

That's the same truck? Wow, nice work!

Did you check the front hubs for runout? Take the wheels off, put a couple of nut on to hold the rotor and give it a spin. Check for any lateral movement. For an absolute check, this should be done using a dial caliper.

You should check the rear brakes as well. even if they are newer, they could have been cheap parts and have already warped. Also check for runout and rust. Another possibility is a bent axle.

 

[Mektek]

I found new rotors with substantial runout. I even had drums turned at oreilly that were only slightly improved.
So if you still have the problem you definitely should use a dial gauge and measure it yourself. I think 6 thousandths was the limit. I had a new rotor with 4 thousandths and the brake pulsation was still noticeable.

 

[Khughes6103]

That's the same truck? Wow, nice work!

Did you check the front hubs for runout? Take the wheels off, put a couple of nut on to hold the rotor and give it a spin. Check for any lateral movement. For an absolute check, this should be done using a dial caliper.

You should check the rear brakes as well. even if they are newer, they could have been cheap parts and have already warped. Also check for runout and rust. Another possibility is a bent axle.

I found new rotors with substantial runout. I even had drums turned at oreilly that were only slightly improved.
So if you still have the problem you definitely should use a dial gauge and measure it yourself. I think 6 thousandths was the limit. I had a new rotor with 4 thousandths and the brake pulsation was still noticeable.

same truck with a little $ and tlc. Thanks for the compliment! I’ll check out the runout tonight as well as the back brakes.