How difficult to install new brake drums

[Taffy_C]

My TT is 17 years old and I've never had work done on the brakes. It's been in storage for a few years and I'm about to bring it out, replace the tires, and do some surface restoration. My question - I figure its probably a good idea to replace the brake drums at this stage and I'm wondering how difficult that is? I'm fairly practical and can use a wrench, but I've never done any significant mechanical repairs on cars or trailers. It seems like I'll save a LOT by doing it myself too.

Any thoughts on how difficult? Any special tools required? Maybe some pointers "how to" posts or videos?

I believe that I have 3,500 lb Dexter axles with 10" drums. I'd prefer to go with self adjusting - current ones are manual.

Also, is it simpler to replace the whole hub/drum assembly vs just the brake kit assembly?

Appreciate thoughts/help.

Daniel.

[ford_truck_guy]

Agree with Gdetrailer....

There has to be something causing the brakes to not work, most probably would be wiring.. Ypu could change everything on the axles and still not have brakes.....

Once you figure out the problem and get them working, then WHEN its time to think about replacing them, I would go with the entire baking plate left sides and right sides... 4 bolts and 2 wires each... easy peasy

[Gdetrailer]

Boomerweps wrote:
IIRC, replacing the whole backing plate assembly isn’t a huge amount over new brake shoes. It’s actually easier than changing out the shoes. And you get new magnets. Apparently, the magnets wear down too.

This I will agree with.

BUT, the OP is thinking of replacing backing plate and drums, just because the brakes that USED to work well are no longer "working well".

OP obviously has had no issues before now with the brakes being strong enough.. But NOW the brakes are no longer working effectively..

Just hate to see folks throw away a lot of money at a problem without doing some basic troubleshooting and pin pointing the cause.

Very easy to throw parts at something and hope it fixes it, much better however is to learn how it works and diagnose properly without becoming a "parts changer".

Good troubleshooting means you need to figure out if electrical, mechanical or both.

You have to break it down into smaller "blocks".

Then narrow down electrical from the vehicle side to the trailer side.

Just throwing backing plates and drums at it most likely will not fix the problem if it is electrical like corroded or broken connections.

While magnets could possibly go bad electrically, they typically don't unless the magnet to drum surface has worn down to the point that the wires have been exposed and then you get shorts until the wire wears out from rubbing.. But once again, those magnets are pretty healthy and should be able to go past 100K miles..

The brake shoes will have sufficient capability for braking until they are worn to much less than the thickness of a Nickle and then possibly into the steel shoes..

I have a 1980s trailer that was originally sold in California and eventually made its way to PA.. I bought it 10 yrs ago, it had sat in a campground for round 10 yrs (have receipts to owner gave me).

I just finally replaced the backing plates 2 yrs ago when the inspection mechanic pointed out that he found one of the shoes the lining had cracked.. The brakes are twice the thickness of a nickle, worked great and as near as I can figure, they ARE the original backing plates.

I would still be using the originals if it wasn't for the lining cracking on one shoe.

Always best to replace in "pairs (left and right) so you have even drag of the brakes, otherwise you will find a "pull" to left or right.

I do want to point out to the OP of this thread.. The backing plates have a "left" and "right" side, they will have a L or R marking stamped on the plates.. When replacing them make sure you use the correct backing plate on each side or the trailer, it will make a difference..

[Taffy_C]

Gdetrailer - excellent thoughts - much appreciated.

[Boomerweps]

IIRC, replacing the whole backing plate assembly isn’t a huge amount over new brake shoes. It’s actually easier than changing out the shoes. And you get new magnets. Apparently, the magnets wear down too.

[Gdetrailer]

Taffy.C wrote:

Gdetrailer wrote:
Good chance that all that is needed is an ADJUSTMENT of the brakes folks, not the replacement of the axles brakes and drums..

Definitely isn't the adjustment because I've checked that and its good on all 4 wheels. I'm rechecking the tow vehicle and controller first and will then check for voltage and buzz on the wheels with voltage applied. Worst case I figure I'm looking at replacing the brake assemblies and the posts in this thread have had a few good links. I also found a good vid on etrailer showing the replacement procedure.

CHECK THE WIRING!!!

Check EVERY WIRE NUT CONNECTION at each backing plate.

But do not "assume" that the backing plates and drums are at fault until you check the wiring!

Bet you will find corroded connections.

If you pull the breakaway pin, does ALL wheels LOCK UP?

If they do then it ISN'T the backing plate or drum or trailer wiring pointing back to a brake controller issue on your vehicle.

Your brake shoes WILL work fine up to and including the point there is no lining on them.. Did you check how much lining you have? You can use the thickness of a nickle to determine if you have enough lining. If lining is thicker than the nickle then you legally have enough lining.

Are you SURE that you have set/adjusted the brakes CORRECTLY?

If you are attempting to set them using the little "inspection" hole on the back of the backing plate, you just might be LOOSENING THEM.

Absolute best way to adjust them is to remove the drum, adjust them then slide drum on. Drum should go on with SOME light resistance.

With wheel jacked up a properly set drum brake SHOULD have a light "drag", you should be able to hear and feel that light drag. If you spin the wheel and it keeps on spinning for many rotations then you have to brakes set way too loose..

Pull a drum off, if it falls off in your hand, you are not setting them correctly. It SHOULD have SOME resistance, otherwise the shoes will never get enough contact pressure when braking.

Drums will have several markings for the diameter and the MAX diameter, you can also measure that but in reality, the max diameter rarely becomes a problem until you have a shop turn the surface down. Finding shops that turn rotors now days is very rare, very few places offer that service. Takes a brake drum lathe, very few auto parts stores have brake drum lathes or the people who know HOW to properly use one. So Drums are considered a consumable but once again, it can be measured and verified before throwing money at the problem.

Magnets should draw about 3A at 12V each, pull the breakaway pin and measure the current, should be about 11A-12A, less than 11A and you have a wiring or magnet problem.

Others on this forum WILL disagree and tell you to replace axles or change to insanely costly pad and rotors..

The system OBVIOUSLY worked well for you at one point in time, something has changed.

Drum brakes have been around since the invention of the automobile, trailer brakes are same principle and for the most part the same parts up until you get to the magnet.. And are pretty easy to troubleshoot and should not require entire replacement of the axles or changing to rotor..

[Mike134]

Edd505 wrote:

wing_zealot wrote:

Edd505 wrote:
Thinking if you need to ask you should likely need help. Brakes are not something to mess with, everyone's life depends on you being able to stop.

Everyone, even the most experienced, has a first time. And with the internet, utube, and the rest it makes easier then ever to learn how.

Well **** I never done one before and should have asked.

The Monday morning quarterbacks would have told you not to even attempt converting to disc brakes on 7000lb axles.

[GDS-3950BH]

opnspaces wrote:
Almost any brake shop or even a Napa with a machine shop can measure the drums to see if they are worn out.

But just think about this. Most every car with 200,000 miles on it is still running the original rear brake drums.

That is if the shop can even find the specs to measure them. Then what?

The typical drums for trailers do not have enough meat to do any resurfacing, they can not be compared to a car drum, they're basically a consumable. Napa and most brake shops will not be set up to resurface the face where the magnets ride regardless. Even the shoes have little lining, Dexter's have 5/32" lining when new. They're designed to be supplemental, not primary.

The entire package can be had on Ebay, Eastern Marine etc for @ less than $200.00 for a tandem.

[Edd505]

wing_zealot wrote:

Edd505 wrote:
Thinking if you need to ask you should likely need help. Brakes are not something to mess with, everyone's life depends on you being able to stop.

Everyone, even the most experienced, has a first time. And with the internet, utube, and the rest it makes easier then ever to learn how.

Well **** I never done one before and should have asked.

[Oasisbob]

My trailer is aproaching 20 years. What you suggest is an easy job. I learned alot from Youtube. You may not need drums. If you went that long with no work I suggest your magnets are shot and drums may not have been working. Won't know til all drums are off. I replaced all four brake backing plates and two drums at a cost of $400 parts alone. Backing plate includes new magnets, shoes.

[ssthrd]

Double post. Sorry

[ssthrd]

prichardson wrote:
It is unlikely you would need new drums unless they have gotten scored by bad brake shoes. The shoes however, would need to be changed if they are worn. The easy way is to replace the backing plate and shoes as an assembly; especially if you want to upgrade to self adjusting.

X2

To answer your question, if you are good wit a wrench, and have done this before, it is not a big deal in most cases. Just remember that you are dealing with 17 years of rust.

IMHO, the easiest way for sure is to remove the backing plate and put a new on assembly; adjust the brakes and slice the wires back on. Done.

If the tires are wearing nice and even, the axles are probably good to go.

IMO of course............ 🙂

[time2roll]

Get your clamp-on DC ammeter out and check for 3 amps per wheel when brake controller is manually applied in full.

Surfaces in the drum could have some surface rust that reduces the grip of the magnet and likewise the grip of the shoes. It would be worth removing one drum to inspect.

[Taffy_C]

Gdetrailer wrote:
Good chance that all that is needed is an ADJUSTMENT of the brakes folks, not the replacement of the axles brakes and drums..

Definitely isn't the adjustment because I've checked that and its good on all 4 wheels. I'm rechecking the tow vehicle and controller first and will then check for voltage and buzz on the wheels with voltage applied. Worst case I figure I'm looking at replacing the brake assemblies and the posts in this thread have had a few good links. I also found a good vid on etrailer showing the replacement procedure.

[Gdetrailer]

deltabravo wrote:

Fisherman wrote:
I'm surprised no one said to buy a new trailer because the ash tray was full.

Or when the black tank was full.. LOL

Agreed!

Like let's "change the axles" because the brakes are not working very well???? :R :h

Good chance that all that is needed is an ADJUSTMENT of the brakes folks, not the replacement of the axles brakes and drums.. And even IF the brakes are worn enough to warrant replacement, you do not need to replace the axles, just replace the backing plates.. 4 Nuts and the plate falls off. Quick and easy job.

The drums unless the brake surface has been deeply scored can be reused and should not need replaced for a long time.

Oh well, this thread certainly has given me a lot of chuckles..