Aahhyes68
Birmingham, MI
Senior Member
Joined: 08/21/2007
View Profile
|
I had our 5th wheel in for a bearing and brake service/inspection and I have a few questions..
We have about 15K on the rig for starters.... Tandem 7K, Al-Ko axels with electric brakes.
One of the backing plates was saturated with grease.. I had it replaced but besides that the other brake sets/backings looked good. The tech pointed out that the drums were extremely "shiney/smooth" as in glass like. He scuffed them up and said they should be okay...
Is there a source of info so I can mic the drums and see if they are within spec ? I've always been told to mic the drums and turn them if there was enough metal so that's what I've always done. I do realize there are two surfaces of contact on and electric brake drum.
We are heading to the Tetons/Yellowstone in a few weeks and I want to have all the bases covered.
Thanks guys. 
2009 Cardinal 38BHQSLE
2008 GMC 3500/CC/D/A
DW,DD & two DS's. Life is good 
|
Gdetrailer
PA
Senior Member
Joined: 01/05/2007
View Profile
|
I would suggest finding another more knowledgeable mechanic to start with.
Brake drum surfaces will get shiny and smooth under normal operation.
What is a problem is if the surface has deep grooves/ridges/scoring or heavy rust and scale anywhere on the braking surface. Out of round (aka run out) also presents some issues too boot.
That scuffing the mechanic did amounts to nothing after one or two miles of normal driving.
To answer your original question, maybe.
Turning the drums depends on how much thickness is left on the drum and how out of round the drum is. The drum should have a max diameter spec on it and the machine shop must not go over that spec.
If drum is too worn or out of round then the machine shop should not turn it.
Honestly though, by the time you pay for having the drums turned you could have bought a brand new set (mechanics and machine shops do not come cheap).
You should be fine to go as is.
|
John Wayne
Long Beach, Ca
Senior Member
Joined: 02/13/2001
View Profile
 Offline
|
The drums should have the Max. diameter stamped in them. The same way there are stamped in car drums.
John & Carol Life members
01 31'Sea View single slide, F53 V-10
96 Toyota 4-Runner auto 4x4 (Remco, M&G brake system)
Security by Bentley
God Bless
KF6HCH
|
ScottG
Bothell Wa.
Senior Member
Joined: 02/25/2005
View Profile
Offline
|
There are a few shops that can do it but it's not recommended. The shoes won't properly seat against the larger dia. drums. They are probably close to or over the max spec anyway.
Drums a fairly cheap so it really doesn't pay the machine them. Check out eTrailer.com.
Scott, Grace and Wesly
2003 Dodge 3500 4x4, 6 speed Cummins (lightly bombed),
2004 Forest River 25RKS many, many mods.
H0NDA eu2000i
|
smkettner
Southern California
Senior Member
Joined: 03/21/2005
View Profile
Good Sam RV Club Member
|
For a couple $$ more just get new drums. And for just a bit more you can get the whole assembly ready to go.
2001 F150 SuperCrew
2006 Keystone Springdale 249FWBHLS
675 watts solar
Send a PM if I missed something
|
|
|
352
Oxfofd, Fl
Senior Member
Joined: 04/20/2004
View Profile
Offline
|
One of the biggest reasons trailer brakes get saturated with grease are buddy bearings. Most everyone thinks more grease is better. What happens is the more grease spins off to your drums and shoes. If you have buddy bearings on electric brakes get rid of them and hand pack your bearings.
1937(BAD BOY)pontiac,all steel,chevy 350,dyno=405hp,650 holley double pumper,ps,pb tilt wheel,heat & air,
700 r4 tranny,headers,3" exhaust with flowmasters
just a good ole southern redneck country boy
Come visit with us and swim with the Manatees
|
mbopp
Henrietta, NY, USA
Senior Member
Joined: 06/20/2004
View Profile
Good Sam RV Club Member
Offline
|
I know my Dexter drums can be turned .090" over. The problem is finding a shop that still has a brake lathe.
2013 North Trail 21FBS
2012 F-150 XLT Ecoboost ("EcoBeast") scab
|
ScottG
Bothell Wa.
Senior Member
Joined: 02/25/2005
View Profile
Offline
|
352 wrote:One of the biggest reasons trailer brakes get saturated with grease are buddy bearings. Most everyone thinks more grease is better. What happens is the more grease spins off to your drums and shoes. If you have buddy bearings on electric brakes get rid of them and hand pack your bearings.
Sadly I think your wasting your breath. People have to learn this one the hard way.
|
352
Oxfofd, Fl
Senior Member
Joined: 04/20/2004
View Profile
Offline
|
ScottG wrote:352 wrote:One of the biggest reasons trailer brakes get saturated with grease are buddy bearings. Most everyone thinks more grease is better. What happens is the more grease spins off to your drums and shoes. If you have buddy bearings on electric brakes get rid of them and hand pack your bearings.
Sadly I think your wasting your breath. People have to learn this one the hard way.
As I did.
|
Don & Linda
Western PA / Cape Cod
Senior Member
Joined: 07/23/2004
View Profile
|
If you trust the shop/tech enough to start your brake work, trust them to finish the job.
15k of normal brake use, is usually not enough use, to require drum renewal.
Above posters are correct. The "max diameter" was cast into drums, but I've seen cheap imports with the max dia. etched into drum outer surface so lightly, that a thin coat of rust would hide the max statement from view. A mfg spec sheet and an inside mic is the only way, to know for sure. Most, good techs can tell by eye, whether the drum is a go, or a no/go.
Be as concerned about the face of the drum(mag drag area)as you are about shoe contact band. The face should be smooth and ridge free, as well.
Dual machining of a elec brake drum is so high, that renewal is sometimes a better option, when needed.
|
|
|
