Some days you just feel like a bone head...

I was convinced the squeal I heard was from the front end. Turns out it was one of my rear pads wearing out. Unfortunately I did not discover this until I returned from out of town and the kids had been driving it with this 'grinding sound' for a few days.

One of the caliper pistons would not retract and just kept digging the pad into the rotor.

After replacing the pads, rotor and caliper (from FPC), everything is just fine. However, I did discover the other rear caliper also has a piston that will not retract! But it's pads are fine.

FCP is showing 'Back order with no ETA' on the right rear caliper. IPD has them, but that's where I got the last set which only lasted 3 years and 15k miles. They're also advertised as the Centric brand like FCP, but the one I received from FCP was sprayed in gold anti-corrosion paint and comes with a lifetime warranty. The IPD Centric calipers came with a grey anti-corrosion paint which did not really prevent any surface rust and comes with a 1 year warranty.

... I'm reminded everyday there is always something to learn. That's the joy of owning and maintaining a 240.

Thanks

The plot thickens...

I cleaned things up (again) on the front, this time more thoroughly. Squealing was not completely gone, but much improved, at least in my opinion. So I left the car to the kids for the week while I was out of town and instructed them to let me know if it got worse.

I came back to the kids complaining of a 'bad noise, worse than before!'. So much for a text or anything during the week. I drove it about 10 feet and hear this awful metal on metal sound. So I hit the brakes and it gets worse, but stops.

I pull my hub caps and see metal shavings on the left rear rim. So out comes the jack and stands, pull the left rear tire and discover the outer pad is down to the metal plate. The inner has normal wear and is of similar thickness as the right rear pads. I wonder if the squealing I had in front was also coming from the back and I was too focused on the front!!

So time to fix the rear caliper (or replace it), service the rotors and get new pads. Then I'll be able to get back to the front squeal.

... it never ends.

Thanks.

Hi,

I'll go with your option of the ????.

Did you have the rotors turned or at least scrubbed the rotors with a coarse sanding, flat spiral, flap wheel, mounted on an angle grinder, before changing the pads?
You can do this while on the car while spinning the rotor.
It's Easier if the calipers were off and hanging but that's up to you and the size wheel you use to do the back side.

It's called cross contamination. Pad material is embedded in the surface pores of the cast iron.
The old pads were or are not compatible with the new material. Even if it's the same brand name pad.
This is why they try to talk you into a rotor turn. If they can new rotors by saying they will be to thin if we turn them. They get an up charge like a funeral home!

The pad manufacturers are always changing their material formulas and can vary in shape. Some add grooves where before they did not and vice-versa.

I clean mine with a nice swirling pattern and remove any ridge on the inside or outside edges that might interfere with new pad seating down. I cut the outer ridge back to almost make a chamfer or rounded edge.

I will also take sandpaper, in your case, and flat sand the pads to rough them up. There can be a glaze built up from them not wearing just as easily. Next choice is change brands of pads.

Try that.

As far as the turning and it becoming louder that the other, well, I'm going to blame that on the turning radius.
One wheel will always be faster in any of those two directions. But my motorcycle experience says you don't lean as far going to the left through an intersection and you go a bit slower making right hand corner turns!
I got pulled over once,min my twenties, by the police for going to the right too fast, by his estimation. I just shrugged my shoulders and said that how motorcycles work! If you go too slow, you fall over!
He let me go with a polite shoulder shrug too!

My disclaimer on turning is Only true here in America or where left hand driven cars are sold!
(:-)

Phil