Approximately a month ago we had an incident on a 12-mile long steep grade (I seem to remember 9%). As a result the rear service brakes became extremely hot, one ABS sensor melted and the rotors and brake pads did not look too good. We had the initial service inspection done at I-State Truck Center in Missoula, MT. I-State recommended new pads, rotors, and seals. Their estimate was $1400 to $1500 and we were not prepared for this expense and I wanted to get a second opinion.
I contacted three senior members of ForeForums, described what had happened, what I-State recommended and asked them if they thought the diagnosis was accurate. Two of the three members responded with an in-depth response with the bottom line being: Get it done.
At the same time I contacted two members of the Escapees Discussion Forum. Both are long-term members and are known for balanced and honest answers and both have extensive technical backgrounds. Those two guys said the I-State diagnosis seemed accurate and suggested we get the work done.
Armed with that supportive information I called I-State last week and asked them to order the parts. {As an aside, I think they figured we would never come back.} I asked that they not specify next day air shipping to save us some money. They were very accommodating and, in fact, did not charge for shipping at all.
Today we drove the 103 miles into Missoula to get the work done. I was able to peek over their shoulders and answer questions. Yes -- they did use the correct clay-based lubricant detailed on Barry Beam's web site. THANK YOU BARRY! Replacement parts were from Meritor.
Both guys couldn't have been nicer or more careful. We were out in just under four hours. The price was as quoted and they even took off $150 to meet their original estimate.
I was amazed at the size and components of the brakes and drive axles. I've not been exposed to this kind of equipment and I feel we were in very good hands. The drive home was uneventful.
Believing in full disclosure because this kind of information helps all of us I discovered a defective tire while at I-State. We have Toyo M154s all the way around. I took advantage of the tires being off the coach to inspect them. One tire had two chunks of tread missing. One was almost the size of 2/3rds of a golf ball and the other the size of a large marble. The marble size chunk had a two inch split in the casing of the tread that was about 1/8th of an inch deep. After we left I-State we drove over to Charles Schwab. A replacement M154 under warranty is on order and will be installed in early September when we leave Thompson Falls and head to Yellowstone. We will not drive the coach between today and that September trip into Missoula. The bad tire is on the rear. The 103 mile trip will be made in the early morning at speeds not exceeding 50 miles and hour and I will monitor air pressure with our Pressure Pro sensors and I will stop and check the temperature with my new Mini IR Thermometer at least twice.
I hope this is helpful to others.
Hi George,
Sorry you had these problems. I am glad you are having the work done before a lot of travel. And last, that's a great price! Best of luck with the new brakes, and tire.
George.... thanks for the info. Any idea what caused the problem with the tire?
George
George,
What was the incident that caused you to have to so over use your service brakes? Don't you have a retarder? Did the retarder get your transmission fluid too hot?
As I have personally discovered, disk brakes which get seriously overheated develop cracks in the rotor. If a rotor fails you can have a real problem on your hands more then likely resulting in an accident. Glad you got it fixed promptly.
George, with the retarded and gearing how did you do that. I have driven mountains extensively and not had that occur. Also the price sounds good if it was all the way around. Make sure they installed them prperly. Many places don't work with air disc brakes. Sounds like they knew what they were doing. Lucky you looked at the tires too.
So how did it happen? Inquiring minds want to know.
Note to inquiring minds:
The brakes and the retarder were not used properly. This will never happen again.
Remember to gear down and to stab your brakes. Drop your sped that way and watch the temps on the retarded. Expensive lesson I guess.
George, did they replace all the way around? Cost?.... Jer
Inasmuch as the rear brakes do the lion's share of the braking on our coaches, these rotors and pads are barely used and did not have to be replaced.
George,
I was wondering how you liked the TOYO tires and I did not know they came in a 275/80R22.5 size?
Looks like you got a great deal on the brakes.
Safe travels and enjoy the cool weather in Montana.
Brad
Brad,
Tires are 295 not 275. I will be chastized for that. So far, so good as far as comfort is concerned. Having a defect show up at 7 months after being manufactured is not encouraging.
George, I was under the impression that our front brakes took up more of the effort and wear faster than the rears. I have replaced my fronts but my rears were ok still.
John,
The brakes are tuned to a rear axle bias, sort of like when you engage the retarder. I don't know the exact bias, if 55-45 or greater toward the rear axle(s). I'm sure James T. can amplify on this subject. A significnt % of the coach weight is at the rear and if the brakes were not biased toward the rear, it would be unstable in slipery conditions as well as "plunge" at the front when applying the brakes.
Peter,
You bring back some nostalgia on brakes. When I drove trucks, they had no front brakes on the 18 wheelers, Seems front brakes did not start showing up until 1975 when the old FMS122 (think that was it) first showed up.
Just for chuckles, and thanks for the bias facts.
Dave
George,
Thanks for posting the name and location of the service center. The price seems to have been very fair too. I have made a folder for "Repair Shops" and a sub folder for each state. Within a given state I will file a WORD doc that has cut and pasted text such as yours.
Hi Rick,
Would you share your List/Folder of repair shops? It would be great if we could go to or have a link to your "site/list" for help in locating a reputable repair shop when in need...
Thanks Peter, I thought they did that but then the question remains, how come the front brakes don't last as long as the rears. I had to change out my front brakes on my 99 but the rears were fine.
Odd, but understand what you are saying about the biases of the braking though.
John,
I was told by Wayne Musser at FOT that, despite the bias to the rear wheels, when braking, the surge/momentum places more pressure on the front end and brakes, exacerbated by the heavy generator sitting in front of the axle.
That would be my thought and also why I figured the feint brakes were working harder on our units dispute the bias in set up.
Every vehicle I have every worked on has had the front brakes replaced at least twice the rate of the rears whether it was front engine, front wheel drive, front engine, rear wheel drive, mid engine, rear wheel drive or rear engine, rear wheel drive. The front brakes work harder because of the weight transference under braking. While DPs and other rear engine vehicles have the majority of the weight on the rear tires at rest, there is far more weight on the front tires under braking. In front engine, front wheel drive cars the effect is worse because with the weight transfer almost no weight is on the rear tires. If you are wondering why front wheel drive cars don't lock up the rears is that they all have a proportioning valve to keep that from happening. Rear brake lock up most of the time will cause a spin, this is why you don't use your retarder when the road is slippery.
A motorcycle performing a "stoppie" is the ultimate demonstration of weight transfer to the front during a stop. The brakes are strong enough that the rear wheel will leave the ground and obviously cannot provide any stopping power. The harder the stop, the more weight is transferred to the front. A coach is not likely to do a "stoppie," but significant weight, and related traction and stopping power, will be transferred to the front axle.