Brake job

Topic: Brake job (Read 1817 times) previous topic - next topic

Brake job

September 13, 2018, 11:34:12 pm

Went by the shop doing the repairs to my brakes. The slide pins had become corroded and prevented the outer caliper from retracting. The drive axle rotors had got so hot that there are a great many small cracks in them. They may have been able to save one rear disc through resurfacing. But those cracks mean new disc's. The front rotors, Bearings & axles look great. But as the fronts had to also do the work of the rears. The friction material had also become hot and had a crack in the middle.
I told the shop that even though the fronts look fine I want new slide pins in those as well.

So far $1,300 in parts. Which includes:
Two rotors
two slide pin kits for rear axle
four sets of pads
slide pin assist springs
Shop will need to order two more slide pins kits and springs for the steer axle.

The Meritor warehouse in Spokane, Washington said that these brakes are the same as Spokane's and a great many other cities transit buses. Calipers, pads and rotors are same for all wheel positions.

Should get the coach back next Tuesday or Wednesday.

Re: Brake job

Reply #1 – September 14, 2018, 07:11:02 am

After you get your coach back, I urge extra caution on the first few drives at highway speed. Stop occasionally to check brake and wheel temps with a non-contact infrared thermometer...just to make sure everything was put back together properly, and is performing correctly. Doesn't take long, and may save you big problems down the road.

Re: Brake job

Reply #2 – September 17, 2018, 10:55:09 am

Might consider getting the shop's recommendations for seasoning the new pads. As you know it's an important step for brakes on a performance car. No idea of what's recommended on a coach.

Re: Brake job

Reply #3 – September 17, 2018, 12:43:33 pm

The Meritor pads do smoke upon first use in my experience. Whether or not my Cummins dealer did the job correctly which I think they did as I watched them most of the way through the new rear pads and rotors had a lot of smoke on first hard use.

They may not have degreased the pads and rotors adequately was my thought.

Each time in use the smells lessened and the brakes worked better and better.

I alternate between the brakes and retarder and downshifting the motor just to spread the work out and not overheat anything.

Coming down a 13 mile grade out of the la mountains Friday I got some brake smell as expected.

Just don't overdue it would be my suggestion

Re: Brake job

Reply #4 – September 17, 2018, 02:24:08 pm

Quote from: Chuck Pearson – September 17, 2018, 10:55:09 am

Might consider getting the shop's recommendations for seasoning the new pads. As you know it's an important step for brakes on a performance car. No idea of what's recommended on a coach.

Normal use after a couple medium to hard stops (but not over use) is all that is needed. Our brakes were designed for trucks weighing much, much more than our coaches. The death knell of the brakes on our coaches is one of underuse/disuse causing the slide pins to corrode and stick than being overused.

I never ever wore out the friction material on any of my class 8 tractors. (Mack CH, Mack vision, Kenworth W900) pulling doubles. When I bought each of my trucks. I simply got in them and drove them. I didn't go trough any sort of initiation ritual and I went ten years with ONE breakdown and that was a micro fracture on a turbo impeller that caused it to explode. I typically had 400,000-450,000 trouble free miles on them when traded in

Re: Brake job

Reply #5 – September 18, 2018, 11:29:45 am

When Brett inspected my coach prior to purchase, the right front brake had more wear that the rest fo the brakes. Next year will be a brake job for sure. Not sure if its something I want to do though considering the importance of what they do....

Re: Brake job

Reply #6 – September 18, 2018, 11:47:55 am

I have just under 100k and the linings are barely worn. I talked to Ron, the PO and he said with the retarder and proper use they just don't wear out.

Re: Brake job

Reply #7 – September 18, 2018, 12:16:51 pm

I agree-- unlikely to wear them out from use.

MUCH more likely to have them wear out from "lazy side" hanging up. That is why keeping slide pins in good condition is important.

Also why Meritor came out with the springs to help force the lazy side to retract (which I recommend).

Re: Brake job

Reply #8 – September 18, 2018, 01:18:24 pm

Quote from: Bob and Julie – September 18, 2018, 11:29:45 am

When Brett inspected my coach prior to purchase, the right front brake had more wear that the rest fo the brakes. Next year will be a brake job for sure. Not sure if its something I want to do though considering the importance of what they do....

When I went to the shop to check out the brakes after they were apart. I saw on the front brake that the caliper simply rotates on the second slide pin after the other was removed and gives full access to the pads. You have to deal with a very heavy wheel/tire combo and have a very robust safety stand that you trust. As well as knowing how to reset the automatic slack adjusters.

Bear in mind that I didn't see them do this procedure. I was just looking at the end result. So it may be more difficult than it appears.

Re: Brake job

Reply #9 – September 21, 2018, 09:50:31 pm

Got the coach back today.
In addition to the brakes. I figured while the wheels and rotors were off. May as well replace the seals all around. Axle bearings were in excellent condition.
$1,600 in parts and $1,400 labor.

I hope this fix it marathon I have been on slows down a bit.

Re: Brake job

Reply #10 – September 21, 2018, 11:30:06 pm

My rotors show tiny cracks thruout the pad contact area -I assumed this was a normal occurance due to the type of cast iron used as all four rotors are basically identical - cracks everywhere.

Re: Brake job

Reply #11 – September 22, 2018, 12:28:27 am

Quote from: bigdog – September 21, 2018, 09:50:31 pm

Got the coach back today.
In addition to the brakes. I figured while the wheels and rotors were off. May as well replace the seals all around. Axle bearings were in excellent condition.
$1,600 in parts and $1,400 labor.

I hope this fix it marathon I have been on slows down a bit.

Maybe at this time, it might be wise to take a deep breath, and revaluate the seals, doesn't seem like since everything is apart the vendor is giving you a discount on this work, at this point it may be to your advantage to renogiate the costs as they appear to be highly inflated based on convenience. I could be totally off base on this issue, but felt the need to respond. Hopefully somebody else can provide input.

Re: Brake job

Reply #12 – September 22, 2018, 12:35:37 am

Quote from: RvTrvlr – September 21, 2018, 11:30:06 pm

My rotors show tiny cracks thruout the pad contact area -I assumed this was a normal occurance due to the type of cast iron used as all four rotors are basically identical - cracks everywhere.

Might be helpful: Bendix (not Meritor) air disk brake rotor inspection guide:

Re: Brake job

Reply #13 – September 22, 2018, 12:44:44 am

Mine are the small ones they say are OK. thanks for posting that!

Re: Brake job

Reply #14 – September 22, 2018, 01:33:19 am

Quote from: Old phart phred – September 22, 2018, 12:28:27 am

Maybe at this time, it might be wise to take a deep breath, and revaluate the seals, doesn't seem like since everything is apart the vendor is giving you a discount on this work, at this point it may be to your advantage to renogiate the costs as they appear to be highly inflated based on convenience. I could be totally off base on this issue, but felt the need to respond. Hopefully somebody else can provide input.

Well. When i called Foretravel parts department. The cost of parts was $2,300 plus shipping on those heavy rotors and pads. that was without the new axle seals front & rear. I asked my shop to replace those seals. They never suggested it.

Re: Brake job

Reply #15 – September 22, 2018, 07:51:31 am

One year ago, discovered inside oil seal leaking. I found this while under my rv replacing the generator fuel line. I had Kaiser Wheel and Brake in Eugene, OR., complete the repair.

As I did not know the service history, of my, new to me Foretravel, they recommended taking apart the calipers, cleaning the pins, using the grey clay grease, and installing spring kits while they had everything off to replace the two front seals. I did this. They said the pads and rotors were fine. They also recommended cleaning and doing the same with the rear calipers (cleaning, grease, spring kits). I just completed that this past week, a year later. As the front was a year ago, the rear pads and rotors were fine.

I have used this shop for over 15 years, have always been pleased with their service and recommendations.

Re: Brake job

Reply #16 – September 22, 2018, 10:14:43 am

Sorry bigdog, i think i misread this as an extra $1600 & 1400 just for the seal portion.

Re: Brake job

Reply #17 – September 22, 2018, 10:40:19 am

Quote from: Old phart phred – September 22, 2018, 10:14:43 am

Sorry bigdog, i think i misread this as an extra $1600 & 1400 just for the seal portion.

Dang! That would have been hi-way robbery for sure.

And what's strange is that given my problems with the lazy side not retracting. The shop showed me my slide pins and they were fine. No corrosion and miked out fine as well. The slide pin bushings however were shot from a life of no lubrication. So all slide pin bushings were installed and clay greased

The passenger rear brakes were the worst. The outside pad had worn down to the metal. (which looked to be the steel see through stuff used on outdoors stairs) but not the actual pad mount. The opposite side still had friction material, But way less than the inside pad. Both rear rotors had lots of out of spec cracks from getting very hot. All remaining pads on the coach had two sizable cracks in them from heat.

Re: Brake job

Reply #18 – September 22, 2018, 11:34:11 am

Having gone through a major brake refurbishment ourselves not too long ago, I am always very interested in reading about "brake issues". I have noticed in numerous threads that the right rear (passenger side rear) brake is in many cases the one with the most wear/damage/problems. In our case, the right rear corner required a new rotor, new pads, and a new axel seal. The other 3 corners had much less rotor wear, and we got away with new pads. I also had new new slide pins and helper springs installed all around, but that was a voluntary preventative maintenance measure.

Anyway, I'm just wondering why the right rear corner would be so apt to have problems? I would think the front brakes would carry most of the braking load, but there must be something about that passenger side rear corner that induces excessive wear.

Re: Brake job

Reply #19 – September 22, 2018, 12:00:51 pm

This thread has me more than a little freaked out. I ASSUMED brake work had been done on Brett's/ours, but can find nothing in the files indicating so. Hard to believe in 170,000 miles NOTHING has been done!

Can the brakes be checked out by just a visual inspection, or do the wheels have to come off to get to 'the heart of the matter' ?

Re: Brake job

Reply #20 – September 22, 2018, 12:30:46 pm

Quote from: mike leary – September 22, 2018, 12:00:51 pm

Can the brakes be checked out by just a visual inspection, or do the wheels have to come off to get to 'the heart of the matter' ?

Mike,

I think the wheels will have to come off. With wheels in place, all you can really see is the inboard surface of the rotor, and the bottom slide pin. To get a look at the (critical) brake pads, outboard rotor surface, and top slide pin, you need to pull the wheels. Sorry 'bout that.

Edit: You can gauge the amount of wear on the pads by measuring the slide pin length that is exposed. (Photo below of front brake)

See Section 13, Page 53 in Meritor manual:

http://beamalarm.com/foretravel-links/PDF/brakes-maintenance-manual-mm4m.pdf

Re: Brake job

Reply #21 – September 22, 2018, 12:56:15 pm

[quote author=Chuck & Jeannie link=msg=326253 date=1537633846 I think the wheels will have to come off. With wheels in place, all you can really see is the inboard surface of the rotor, and the bottom slide pin. To get a look at the (critical) brake pads, outboard rotor surface, and top slide pin, you need to pull the wheels. Sorry 'bout that. Edit: You can gauge the amount of wear on the pads by measuring the slide pin length that is exposed. /quote]
Thanks, Chuck, sorta figured that the wheels had to come off.

Reading the manual (thank you) and going through the files again of Brett and the POAB (previous owner after Brett) I'll get more of a grip. They seem to work fine, no noises, tho have never had to 'dynamite' them. I have a feeling that using the Pac Brake a lot has plenty to do with the brake life

Re: Brake job

Reply #22 – September 22, 2018, 01:22:17 pm

The U225 and U240 have completely different brakes.

They are wedge design drum brakes. Much less problematic than air disks (and, yes a little less braking force). Lots of medium duty trucks in U.S. and Europe used that design.

Re: Brake job

Reply #23 – September 22, 2018, 01:34:21 pm

Quote from: wolfe10 – September 22, 2018, 01:22:17 pm

The U225 and U240 have completely different brakes.

Mike,

Disregard everything I said...

Re: Brake job

Reply #24 – September 22, 2018, 01:45:02 pm

Do not lube the pins

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