If rear pads are improperly mounted it is possible for uneven wear to occur. Pad raised stud must be aligned w/ slots on the caliper piston to prevent misalgnment. I checked the 03-06 shop manual and this was true for those years. Probably same for yours.

A careless brake installer might miss this detail, and it might cause noise.

good luck

 

The sound at the console may be from the shift lock; however, on my car, I don't hear any noticeable sound when pressing the brake while in Park.

The switching of rear caliper slide pin A and B were to help with the rear brake pad wear. It should not cause any rumbling noise, even if there were not switched. You can still check the condition of the slide pins for corrosion and re-grease them with silicone brake grease. There was no TSB for the rear brakes. The instructions were included as part of the revised Honda brake pad kits from the dealer. There was info. regarding revised rear brake pad part numbers, etc. as part of Honda service news; but, doesn't include the pin switching instructions; the monthly Honda Service News is not exactly the same as Honda's issued TSBs.

Lack of grease on the slide pins can cause some noise when braking.

 

Agreed. The tab on the brake pad should be aligned with the cutout on the piston when installing the rear pads. See attached pic. It is the same on your car.

 

I have the same year accord, with the same engine and I usually get 25-26 mpg. That is city and highway driving.

 

Goldwinger and redbull, thank you very much for your help, it's nice to know I'll actually be able to fix the problems with the rear brakes instead of just having to deal with mediocre rear brake pad wear and overall quality. The rumbling noise comes and goes, I think it might have something to do with the colder weather, not quite sure. I'll look into the examples you guys have given me, thank you very much.

Last two questions. I've established the fact that I'm not getting the right mileage. My car has 80,000 miles on it, I'm not sure if that has to do anything, I'm just trying to rule out all possible scenarious. Besides driving more conservatiely, what else can I do? I really don't want to settle with 21-22 MPG on highway. It's an Accord, not a midsize SUV.

And finally, with the switching of the pins, is this something that can be done in your own garage or do I have to drain my wallet by going to the dealership? I'm just curious.

 

The rear caliper slide pins may already be in the proper position, since you had the pads changed before. This is a copy of the instructions, normally included with each of the revised Honda rear brake pad set.



You can easily do it in the garage.

• Loosen the lug nuts; but, don't remove.
• Jack up the car and support with jack stand(s).
• Take off wheel.
• While holding the caliper slide pin with a wrench, remove the flange bolt. (Repeat to remove the other flange bolt on the caliper.)
• Remove caliper and support with a wire or something, so it doesn't hang.
• While holding the caliper slide pin, with your fingers, gently slide the rubber boot off the ridge of the slide pin and pull out the slide pin.
• Check whether caliper slide pin A and B are in proper position.
• Examine slide pin for pitting and corrosion. Clean or replace as necessary and re-lube the slide pin with some silicone brake grease.

One of our member's has a picture tutorial:
Honda Accord Premature Rear Brake Pads Wear - Replacement & Repair Guide - 2008-2010 Model Years, 2009-2010 Acura TSX - Picture Illustrated DIY Instructions