Them's the Brakes

[Keith Moffett]

I havent found a reference to this so here's the question.
The manual says use silicon grease to lube the brake caliper slide rails once each year.  The shop tells me that the tires must be removed all the way around to remove the bolts for the rails.  Seems like there has to be an easier way if it is done yearly.
The system is air over hydraulic with four wheel disk.  I have no record of this ever being done so I'm thinking its as dry as they look and more.
Thanks much for any input!
Keith

[Marty and Suzie Schenck]

On the 1998 Monterey I had in 2003 I had the same problem. The first year I put it up on blocks and had a tire guy come by and remove the tires and wheels. I then lubed the caliper slides and the tire guy came back and installed the wheels and tires.  For the next 3 years I blocked up one wheel at a time and then sprayed the lube through the hole in the wheel lining it up to the lower and upper slide rails. I also had to connect 3 of those little red sprayer tubes together. It was a little tough at times but it did work and I never had any brake hang-ups. Hope that helps. Marty

[Gerald Farris]

Your shop was correct when they said that you need to remove the wheels to service the brake calipers. The once a year service schedule is a worst case scenario that assumes that the coach will be operated on salted winter roads.

If the brakes have never been serviced on a 12 year old coach, you are pushing your luck, however if the coach is not operated under corrosive conditions (salted roads, salty air beach areas, or stored in very high humidity) you can probably get by with checking the brakes for wear and cleaning and lubricating the caliper slides if necessary ever 6 or 7 years when the tires are replaced. However if your brake pads are getting thin or if corrosion or rust are present, more often services would be necessary.

With the type of brakes on your coach a lack of service can result in the caliper sticking in a partially applied condition that will overheat the brake and possibly cause a complete failure of that brake, so the cost of a brake service can be money well spent.

I have full air disk brakes on my coach and I check the brakes for wear and lubricate the calipers every other year.

Gerald

[Keith Moffett]

Thanks Marty and Gerald, all that helps me put some perspective on it.  I am considering having it evaluated in Bend after the rally.  Problem is the labor is almost the same as replacing the pads so why go half way.
Perhaps Gerald can tell me how thick the pads are new so I can tell how far gone they are?  I dont want to have it go out on my way through the mountains.
Thanks guys!

 
Hey Marty, what were you using to spray them with?

[Gerald Farris]

Keith,
I have never replaced the brake pads on that particular brake system, but I would estimate the new lining thickness at somewhere between 3/4 and 1 inch.

I do not know how much the brake pads cost on your coach, but the OEM pads on my Marquis cost $175 per wheel. So do not expect your brake pads to be in the $10 to $20 range that some cars cost. If your pads cost in the same range as the pads on my Marquis, premature replacement would probably not be advisable.

The one year service interval that the owner's manual recommends is probably more for product liability lawyers than for coach owners, although I am sure that there are some operating conditions were it is advisable. The one year service interval could otherwise be known as the CYA approach to prevent law suits. Beaver Coach Sales in Bend can probably tell you how often they run into problems from lack of lubrication on coaches like yours that are used under different conditions.

Gerald

[Marty and Suzie Schenck]

Keith, I used CRC White Lithium grease in the spray can.

[Keith Moffett]

Big big help.  Thanks to both of you!

[JimCasazze]

I wish I had read this thread a week ago.  My left front caliper stuck and caused the wheel to get scorching hot.  I didn't even realize it was stuck until I stopped at a toll booth, opened the window and smelled the burning smell.   The truck repair center is replacing the caliper and pads, but now I'm wondering if they could have simply freed it up and lubricated it.

I thought it would make sense to change the other side as well assuming if one went the other will not be far behind.  I should have checked here on the BAC forum first!!!!!

Hope someone else reads this and takes note, so they won't go through the same.....

J

[Keith Moffett]

Jim
Here is the final news on the caliper slide rails.  I got the wheels removed and the calipers as well. They can be loosened and just set up off the mounting so there is no bleeding the fluid later.
When pressure is applied to the brake, the caliper and pad grip the rotor, so if the rail is badly coroded it will not release or 'float' as it should.  The resulting heat will cause bluing on the rotor and heat cracks.  Coachmasters in Bend showed me one they just fixed that disentigrated on a coach.  The wear ate right through this rotor, so no breaks and a deadly situation.
I had our rails cleaned with a wire wheel and lubed with silicone grease.  The result bas much better breaking and no drag so better fuel mileage.

Glad you are all ok and I hope someone does read this.  Thanks to Gerald Ferris for his information, suggestions and support.

Keith

[Edward Buker]

I have some reservations about trying to spray the slide rails with the wheels on given they sit above the pads and the lubricant in spray form is propelled into the area possibly getting onto the pads. The parts that need to slide are mated surfaces that are not readily greased or cleaned without being disassembled and this is certainly not an area that you have adequate access and visibility to. In addition the grease on surfaces attracts and holds dirt.

Cleaning the slides and adding a minmal amount of Hi temp caliper grease in assembly when pads are replaced would be my choice. I believe that the lubing of the brake slides is something in the Beaver manual but not a mantenance item in the Meritor Brake manual. As Gerald stated this is probably a liability prevention clause. If my coach was driven in salt or sat for long periods in a damp environment (especially after being driven in salt) then I would have the brake caliper slide surfaces/pins adequatly cleaned and lubed.

Exercising your brakes once a month even if you only move the coach a few feet will help prevent this problem. In the meantime what I do is measure the wear indicator pin on the backside of the brake assembly using a 6inch metal rule with a slide stop on it and record that value for each wheel. The Meritor air brake calipers have that feature but I am not sure if all models do. This measurement takes about 30 seconds per wheel. I also measure the rotor temperatures once in awhile when on the road with an IR gun to see if they are similar. A good time to do this temp measurement would be on a check out run after any long term storage or staying long term on a campsite. If the wear and rotor temperatures are uniform within reason per axle then the slides are functioning as they should. While this is not prevention, it does check on the current health of the brake system.

I applaud anyone trying to be diligent with maintenance and I also looked at spraying those surfaces with the wheels on but concluded that I would probably do more harm then good. If you have any doubts about your brakes performance then by all means have them adequately checked out. Hope this helps.

Later Ed

[Marty and Suzie Schenck]

So Ed, is what you are saying about spraying the caliper slides with a high temp silicon gease through a tube directed at specific surface the wrong thing to do. I have had no binding caliper problems with the 98 Beaver air over hydraulic disc brakes for the 3 years I owned it and have not had any caliper problems with my 2002 Thunder air over air disc brakes for the 5 years I have owned it. I do this once a year when I service the coach and it seems to me that it works fine. The grease is not being sprayed all over the area, it's being sprayed through that little red tube at just the area that needs to be greased!
Marty

[Gerald Farris]

Just a note of caution here. The original post to this thread was about servicing the calipers on a SMC era Patriot with hydraulic brakes, and Ed is referring to servicing the calipers on a SMC era Marquis with Meritor ADB (air disc brakes) brakes.

While the two have some similarities, there are many differences in the way that the calipers mount, the lubrication requirements, clearances involved, and the method used to check pad thickness. So any coach owner should know their brake system and develop a maintenance schedule that fits their coach an driving habits.

Gerald  

[Edward Buker]

Marty,

 I'm not saying that it is the wrong thing to do and I'm certainly not trying to tell anyone else how to maintain their coach. On my coach I looked at that job with the wheels on and it was an impossibility to effectively lube the mating surfaces on the Meritor design brakes without disassembly. That gives me reservations about most people that read your post and head out with a spray can and think they can effectively "lube the brakes".

 My caution would be to know your own brake design and have a clear understanding of the mating surfaces that need to be lubed. If you have access to those surfaces and can really inspect them with the wheels on, the rust level is not an issue, and you can effectively lube them with a spray can and tube without getting grease where it should not be, then by all means have at it. Just be sure of the technique, they are your brakes....

Marty, your knowledge and comfort regarding your braking sytem has been earned with a history of good performance, so no need to mess with success if you are happy.  Just thought it wise to throw some caution in here on the subject for most of us...

As always, thanks Gerald for your insight on this.

Later Ed

[Keith Oliver]

I want to know what car has brake pads for $10 to $20 per wheel.  None that I have ever owned.
When I was under my Contessa with the PDI guy, he told me the pads looked "nearly new"  They were about 1/2 inch thick.