P-30 Disc Brake Squeal

[Bill_Carry]

RVis 1994 Chevy P-30 with discs all round. Owned since new. Have 220,000 miles on it.

First front brake pad replacement @ 71000 miles with name brand aftermarket pads brought on lots of squeal. Someone suggested using only GM/Delco OEM pads. I changed the pads to GM/Delco right away and got rid of the squeal. Replaced the pads with GM/Delco again at 170,000 miles. No squeal.

This spring I replaced the pads at 220,000 miles, again with Delco. This time i get the front brake squeal in spades.

Anyone know if Delco stopped the OEM compound for these old brakes or any other reason for this problem. I know that the P-30 was famous for front brake squeal but thought I had the problem understood and under control.

Would appreciate any shared experience or advice.

[jyrostng]

the auto supplies have a spray for the lining to caliper contact area that is supposed to help this when you change pads.

[Gjac]

Some brake pads are also slotted, I just changed pads on my tow car and the pads had a slot in the middle of the pad.

[topflite51]

During my working days, on several vehicles I changed rotors to slotted style to eliminate disc brake squeal. (Expensive) It also wore out pads faster.

[BULLETLS1]

Some brake pads come with a pouch bag with some sort of adhesive(probbly is hi temp silicone painted blue!), its applied in the back of the pad , circular in the side of the piston, H shape in the opposite and on the edge of the fulcrum.
What happens is that the pads grab and for a fraction of a second they become stationary with the disc, thus microscopically vibrating, and slaping against metal to metal... this adhesive-lubricant keeps metalic parts to slap each other

[Gjac]

I just had my front brake pads changed yesterday after 107,000 miles and they squeal also. As a side note I had about 1/8 in of pad left on the L/H side and 1/4 in on R/H side.

[2bzy2c]

Did you turn the rotors? If not, that might be the problem.

[tropical36]

I've had a lot of squeals no squeals and such. With ours, it's usually OK with new pads for awhile. Last time I did it myself the best pads from NAPA and I think Ceramic. Now they have begun to squeal again, when they feel like it and I've decide to just let them go ahead and cry, if it makes them feel better.
If it really aggravates, try spinning the wheel without the cover installed and spraying brake cleaner on the rotor. Might help for awhile, anyway.

[garry1p]

Mine did that for a good 1000+ miles and no longer squeal!

They started squealing soon after the new pads were installed.

[rgatijnet1]

Where were they made? The AC/Delco idler pulley that I got was made in China, which could explain the problem.