I have some of the CRC Brake Quiet product (that red gel stuff). I know I'm supposed to apply it to the back side of the outer pad where the metals contact each other, but should I apply it to the back side of the inner pad also?

Is this a good product? I saw an aerosol brake quiet product at the auto parts store also, but I bought the gel.

I would. I believe all it does it make sure the parts don't rattle/vibrate against each other causing a lot of ruckus.

use the gel as the spray coats too wide of surface & is wastefull & it attracts debris. Yes it works well & use it sparingly only on the contact points & yes on the inner pad. the outer pad needs its ears crimped so it is solid whereas the inner pad needs some clearance to float but hit the areas(w gel) where the back of the pads contact anything

I had a couple of cars that were driving me crazy with squealing/squeaking brakes.

We put the disc brake quiet on the back side of the pads where the caliper/piston touches them and it worked perfectly!

The reason I ask is because the inner part with the rubber around it is the only area that the back side of the pad would come in contact with.

when your buttoned up ready to go the piston will be out past the dust seal making metal to metal contact

Got it