Wheel Cylinders
The fluid leakage did not show up in your earlier photo's. Are you sure you didn't accidentally hit the brake with the drum off (I've done it)? This would pop the pistons out of the cylinder bore. At a minimum, you now need to bleed the system.

Again - if you can't center the pistons in the wheel cylinder, you either have a frozen piston or a stuck parking brake cable.

Pulling the wheel cylinders may not be fun. Make sure you use a penetrant on the brake hard line (hours or days) or you may twist off the hard line. The bolts themselves are prone to rusting and "rounding off" when you try to remove them. Use a good quality box wrench or socket (if it will fit). Have a plan B if you loose the hardline or bolts.

If you replace one - do both. Wheel cylinders normally stick because of moisture in the brake fluid (corrodes the OD of the cylinder). Make sure to completely flush out of old fluid to remove any moisture. Also - do not let air get into the ABS pump/valve. There are posts on the forum on how to do this.

Drums
Your original noise was likely due to the rust on the drum groove where the backing plate inserts. As the drum rusts, it reduces the gap between it and the backing plate. Use a wire wheel/screwdriver/chisel to remove the rust from the groove. Use a respirator!

Your drums also appear to have a pretty good ridge on them. I use a abrasive wheel on a die grinder to knock this down. Many people use a angle grinder to do the same. Use a respirator - nasty stuff.

General
The rear view of the backing plate does not show a rubber plug for the self adjuster. Make sure you re-install one or your new shoes/hardware will quickly rust away again.

What year vehicle is this? London ON would definitely qualify as the rust belt (I'm in northern IN - similar problem). You're rear drum's are more rusted than my '97. Have a good look at the backing plate (use a wire brush and prime/paint) and your brake lines.

I just got through replacing all the hard lines on my '97 after a double line failure (primary and secondary systems). I was extremely lucky that 1st the line ruptured while my daughter was backing down the drive. The second line blew while I was pulling the van into the garage. I can't imagine what I would have done if someone had gotten hurt. I thought my vehicle was in good shape - make sure yours is.

 

Terrific info. Much for me to digest as a noob. I will pull up the service manual and follow your instructions to get this thing resolved.

I will get back to y'all shortly!

 

The vehicle is 2002 and i don't think it has had its rear brakes ever serviced.

You mentioned the ridge on my drums. From the diagram below which area are you referring to? I want to make sure i target the right spots. And the groove you mention i assume that is location (B); i have yet to fully inspect the drum and how it actually sits on the backing plate.

Thanks.

 

I added arrows to the "ridge" in your photo below. This is making it more difficult for you to re-install the drum.

You are correct that the "groove rust" is in area "B" in your photo. The backing plate insets into this area. Not a safety issue, but it will drive you nuts when the backing plate grinds against the rust.

I can't tell from your photo whether the shoe area of your drum is rusted or glazed. Either way it doesn't look particularly good. Clean it up with some sand paper (circular motion) so your shoes can get a good bite.

Here's a post with some photo's of grinding the ridge and sanding the shoe area. http://www.handymanlyness.com/archiv...96_Dakota.html

Alternatively, you may want to check out your local parts stores. I buddy of mine just told me that our local O'Reillys auto resurfaces drums "while you wait". Worth a shot if you don't have a grinder (or don't want to eat rust). They will probably NOT clean out the drum groove.

 

Incredible assistance you've given me IndyMike. Thanks so much!!!