Damaged Brake Backing Plate (Rear Drum Brakes) Gen 2

I have a 2006 Tacoma 4WD 6Cyl. My best guess is that the rear drum brakes have never been serviced. On the right wheel I used the bolt trick to readily remove the drum. On the left side, it took hours of effort (hammer, prying etc) to break the rust "weld" and get the drum off. In the process, I damaged part of the backing plate.

There is a flexible metal gasket that fits into the groove of the drum (see picture). It is made of a soft metal alloy and I guess it partially seals to the drum. That part was damaged beyond repair and I pulled it out. It is tacked onto the backing plate (with a few tack welds it seems). Nevertheless, it was easy enough to remove. Everything else is good and I managed to service the brakes and install a new drum with a kit from Rock Auto. The gasket thing is part of the backing plate and you can't buy it separately. I have no problem with buying a backing plate (~ $110). However, I a very worried about installing the backing plate because it is probably out of my league since it opens up the hub.

Here are my questions: Do you really need this "metal gasket"? I was thinking about buying a new backing plate to extract that piece ($110) and then removing the metal gasket and tacking it in with spot welds. Ideally, I just want someone to tell me, I can live without it.

Please let me know if anyone has recovered from this without installing a whole new backing plate. It sounds painful!

 

I tell you this, the axle, the wheel cylinder, and all the brake components have to come out to replace it. I did this once when replacing the axle seal. I wouldn’t do it again for a Backing Plate “Seal”.
Unless someone can give a REALLY good reason why I should.

That whole process was no fun at all.

 

I hear you! That piece can't even really touch the drum. They are a close fit but not a seal. So water and crud still get in there obviously. I think I am better off opening it up once a year and cleaning it out than trying to install a new backing plate. I am just hoping for some moral support and to know this is not a crazy idea. Thank you for your feedback about the difficulty of installing a new backing plate!

I know on the front disc brakes people just run without the backplate to avoid the hassle.

 

I haven't done them on my Tacoma since I haven't needed to but I did replace both on my old T-100. I would THINK it is similar. It was as 'simple' as removing the brake line, the parking brake cable and the four nuts that hold the axle flange to the rear diff. Then the whole assembly slides out.
I don't recall if that backing plate replacement required the separation of the bearing assembly, but I don't think it did. I didn't think it was too bad of a job. See if you can find some YT videos on it.
Again, as I recall, it wasn't horrible. I'd guess you could run it like it is but you're likely to get more road grime into the brake assembly and accelerated corrosion.
If it were me, I'd probably replace it. I do however, value TnShooter's opinion. He's always one of the helpful, straight shooters on this forum.

 

Not to be critical, but did you back off the brake adjustment before you forced the drum off?

If you had it would have saved you all the time and damage. It could help you next time.

 

@winkel - I will definitely check this out! Thank you for the heads up. For now I am going to order the backing plate. I will either (A) remove the metal gasket and attach to the plate I have. OR (B) just install the new backing plate if the procedure is withing my capability and pain threshold.


@Jimmyh - Yes, I did back off the brake adjustment and released the ebrake. The issue was rust bonding. The wheel was spinning freely. The truck has relatively low mileage (72k miles) for its age (15 years). It looks like nobody has looked in there in years. The picture I posted is not my truck but shows that collar/metal gasket that was damaged. Mine is badly rusted and filled with dirt and grime. The previous owner lived in Mass. (read lots of salted roads during winter) and the main issue I have found reclaiming the truck is rust.

 

Most drum brake setups don’t have that metal ring and work just fine. I’d run it without it.

 

As a side note, as your brakes wear into the drum, it forms a ridge at the top inside edge of the drum (as your drum would sit on the bench like a cereal bowl). This undercut is what makes them such a sumbich to remove. I pull my drums every couple of years and carefully remove that ridge with my angle grinder and a flap wheel disc. I know this is a little anal/ocd, but it sure makes drum removal easier for the occasional cleaning and regrease on the contact points.

 

@Bashby - This is very helpful to know. I feel better already! It may be until summer before I try anything creative. I have a backplate on order to extract that metal gasket/collar but I have to live my life too. Fixing the truck can only take up so much of my life. So no matter what I will be running without it for a while.

@winkel - I hear you! The old drums are in the bed of the truck for recycling. The new ones are on! Also, I coated all the contact areas around the hub (near the lugnuts but not on the lugnuts) with a copper anti-seize compound. I hope that helps for next time!

 

Its fine, I wouldn't worry about it

 

@Jimmyh - I do appreciate the reminder about the adjustment. And I especially like the drawing and excerpt because getting the setting adjustment right during install seems to be kind of a "feel it out" thing. I don't really have that feel yet. Now, through your excerpt, I have the 'official' procedure. Score!

 

It is always good to be prepared.

 

The weather (and my mood) finally improved enough for me to dive back into this project. Being the OCD person that I am, I purchased a backing plate, drilled out the weld points and removed the infamous metal collar / gasket. I then drilled some through holes into the collar and my existing backing plate (the one on the truck) for some #8-32 flat head screws. I used stainless "aircraft" nuts (with the nylon insert to prevent loosening) and permanent lock tight on the back side to secure the collar. I doubt this did much but if it is important, I have it back now! I wanted to use #10 bolts but the head was too big. The #8 flat head clears the drum when it is installed and there is no interference. Time to call this one done. No need to mess with the hubs. Thanks to all those that advised me on this!

PS During the time I was running without that collar, I didn't notice a thing. My guess is that there is some perfect size pebble that could work its way through during an off road situation. There is a 1 in 1000 chance that that pebble could cause problems inside the drum. With the collar installed properly maybe it is 1 in 10,000 chance. Just my guess.

 

Awesome. There’s always more than one way to do things.
You found the alternative!

My problem at times, is figuring out the alternative.