Community Forums

GDwinston · 06-04-2018, 12:08 PM

Lubing chassis on 2008 Monaco Diplomat RR8R, no backing plates in rear drum brakes is this normal. The drum and brake shoes are totally visible water and road grime could easily end up in the drum.

CountryB · 06-04-2018, 01:00 PM

It's normal.
They would not be much protection against water since they are a loose fit (think how your disc brakes are exposed). In the trucking industry they are typically found removed so the owner/driver can easily inspect the lining wear and oil seal.

If it was my coach, I would leave them installed and just remove annually for inspection. If I did not have them already installed (which I do not on my tag axle), I would not spend the money to buy a set.

zmotorsports · 06-04-2018, 02:54 PM

Yes that is normal. No backing plates, the shoes are exposed. This allows a quick visual of your shoes as well as looking for signs of oil and allows the use of a go/no go gauge without having to pull tires and drums to check.

Mike

luckyd · 06-06-2018, 10:01 AM

We did not have backing plates on our coach
when we bought it. No problem......UNTIL.
We drove through a snow storm, wet road slush.
Parked in an rv park for the night. In the morning,
fired up, aired up, released the brakes, and the coach

did not move. Touched the throttle and heard a clunk,
but the coach moved. Felt like the back brakes had locked
and then released.
Same thing the next morning.
Made it home and parked for a couple of weeks in warm

weather. Took it in to the shop and they found nothing wrong.
They then said we had no backing plates and asked if we drove through
heavy rain or snow. We told him the story.
They felt the shoes got wet, stuck overnight, and had dried out
when we got home.
He did say that there is a possibility of hitting the brakes and them
locking up when they get like that. We installed plates. ($30/plate)

Disc brakes are totally different than drums.

CountryB · 06-06-2018, 10:24 AM

When I worked as a truck mechanic in the north (many many years ago), I would come across trucks with the drum brakes frozen (the lining freezes to drum) due to water sitting in drum overnight.

But this happened whether or not there was a backing plate installed. Having a backing plate just seemed to add an extra step to the repair (the removal of the backing plate).

Since the drum generates heat during braking operation any snow or water that hits the drum/lining while in operation is not an issue - it's just the morning start up where this shows.

Now it may be true that the total number of frozen brakes was higher on the trucks without backing plates - that I don't know.