Go Back   iRV2 Forums > THE OWNER'S CORNER FORUMS > Alpine Coach Owner's Forum
Click Here to Login
Join iRV2 Today

Mission Statement: Supporting thoughtful exchange of knowledge, values and experience among RV enthusiasts.
Reply
 
Thread Tools Search this Thread Display Modes
 
Old 08-15-2009, 08:20 PM   #1
Member
 
Join Date: May 2004
Posts: 72
Bosch ZOH T Slide pin caliper brakes

After the recall about Bosch brakes installed on our Alpine 02 the calipers were replaced with the ZOH T type. Now I see a recall notice regarding several Motor Home Mfgs. about the ZOH T calipers. Since WRV is no longer in business I would like to know what the problem is.
Reason I want to know is driving From Eagle Nest, NM to Taos, NM the road is very winding on the down hill side. When we got on the flats I smelled the brake pads overheating. This has never happened before even under more severe braking conditions. Would appreciate any comments as to what the recall is about and what is the remedy.
__________________

__________________
doug ABQ is offline   Reply With Quote
Join the #1 RV Forum Today - It's Totally Free!

iRV2.com RV Community - Are you about to start a new improvement on your RV or need some help with some maintenance? Do you need advice on what products to buy? Or maybe you can give others some advice? No matter where you fit in you'll find that iRV2 is a great community to join. Best of all it's totally FREE!

You are currently viewing our boards as a guest so you have limited access to our community. Please take the time to register and you will gain a lot of great new features including; the ability to participate in discussions, network with other RV owners, see fewer ads, upload photographs, create an RV blog, send private messages and so much, much more!

Old 08-16-2009, 06:24 PM   #2
Senior Member
 
Join Date: May 2004
Location: Auburn, CA, Havasu, AZ & Mulege, BCS
Posts: 5,217
Doug- hop on over to the Workhorse forum here on iRV2 and don't even bother w/a search. Just start reading the threads that have "brake" in the heading, and you will learn all about the recall. There is a link, in the sticky threads @ the top, to the Workhorse recall notice that gives more info on symptoms.

The problem appears to be in a bakelite lining of the Bosch caliper pistons on their pin-slide style calipers. The plastic lining absorbs water over time, and when the brakes heat up the lining can expand, stick in the piston bore, and lock the brakes on. W/additional heat you can boil the brake fluid, leaving the brake pedal spongy or maybe go all the way to the floor. Symptoms include smoking brakes, a wheel end fire, loss of braking, stuck brakes causing drag, anger, road rage, and liberal political attitude. The new calipers are not yet commercially available, but Bosch is "working" on them. Rumors say maybe October or November, tho rumors are not specific on which year (that's a joke, presumably that will be this year). Workhorse has something like 47,000 motohomes in their portion of the recall.
You could try contacting Bosch to find out if there is recall relief for owners of defunct chassis designs, as the brakes are the same on the early Alpines (zops or zoht pin-slide brakes are both in the recall).

In the mean time the best thing is to immediatley and fully flush your brakes w/fresh DOT3 brake fluid, then maybe do it again in about 2 months. This will eliminate most of the accumulated water in the system (brake fluid is hygroscopic- absorbs water from atmosphere) which will minimize possibility of recurrence. No guarantee as how much water may be in your brake system is not possible to determine; also there is some random amount of recurrence per the WH postings even with flushing altho most seem to go along nicely after the flush. I'm wondering if maybe part of the problem is a bad Bakelite formulation, but that's all academic.

Later Alpines that have Meritor quad-piston disc brakes are not involved, and it does not involve the Bosch HydroMax master cylinder common to all Alpines.
__________________

__________________
Baja-tested '08 2-slide 36'
Alpine: The Ultimate DIY'er Project
EngineerMike is offline   Reply With Quote
Old 08-17-2009, 07:49 AM   #3
Member
 
Join Date: May 2004
Posts: 72
Bosch ZOH T Brakes

Thanks for the info from "engineer mike". Now the question is do I get the brakes flushed and keep on driving. After the initial overheat the brakes acted normal. Any opinions appreciated and will not be taken as "so and so said it would be ok"

Doug 01 Alpine MDS 80,000 miles enjoyed.

__________________
doug ABQ is offline   Reply With Quote
Old 09-16-2009, 07:23 PM   #4
Senior Member
 
Join Date: May 2005
Posts: 163
I have had the brake lock up issue on my 01 Alpine as reported in the Workhorse chassis thread. I have had the pins lubricated on a regular basis, but had not had the brakes bled and new fluid in about 3 years. I did not loose my brakes, but on pulling into a rest area the brakes were obviously hot, smoking and lost the ABS sensor, fortuneately no fire. I had been going down a steep stretch of the Icefields parkway into Banff and had geared down lower than 4th so I was not riding the brakes, but the left rear still locked up. After a half hour I proceded on our trip, 2000 miles more, and was very ginger with the brakes by downshifting even more and had no more serious problems.

Today I talked to NHTSA concerning the Recall Campaign 09V110000 on this issue on the Workhorse Chassis. I was told that I would have to contact Workhorse for relief on the WRV chassis under the current recall. Fat Chance that they have any interest on working on an Alpine. Therefore, I have filed a complaint relative to my rig on the same issue. They will have to open a new investigation as the one above is closed. I suggest that anyone with an older rig that has had these problems with the Bosch brakes contact NHTSA at (888) 327-4236. I talked to Cynthia.

I also talked to Bosch today. They said that they "HAVE NO RESPONSIBILITY". The position stated was that they have no control on how a manufacturer uses their product so they cannot be held responsible. On the one hand I understand their stated position to protect themselves, but I am dumbfounded that they have no interest in even following up on the situation. The representative suggested I take it to a shop to have it repaired. I would bet they would have a very different reaction if a major fire or accident happened as a result of a brake failure when a recall is in place on another RV, which I assume they are standing behind Workhorse on.

Bottom line if others have a problem with Bosch Brakes suggest you call NHTSA at the number above.
__________________
2001 36 MDDS
03 Honda Pilot toad
jetar is offline   Reply With Quote
Old 09-16-2009, 08:59 PM   #5
Senior Member
 
Join Date: May 2004
Location: Auburn, CA, Havasu, AZ & Mulege, BCS
Posts: 5,217
Jet- Bosch is correct that when a mfgr specs their brake component, it is the responsibility of the mfgr to see the usage is correct. Bosch claims, probably w/some fact based reasoning, that the recall is a use-based problem (i.e. motorhomes where the coach may sit for long (~5 month) periods not used have the lock up problems, and that the same brakes in delivery vans that drive all day every day have no such problems. Workhorse makes both types of chassis'.

IIWY, I'd hang tight till the Bosch recall calipers are in use (probably take till spring next year w/the backlog) and you can order rebuild kits w/the new pistons or order whole new calipers (depends on cost ut the door IIWM). In the mean time, bleed your brakes regularly, and drive the coach every month for 50 miles at least to a fabulous resort where you can order tropical drinks with little umbrellas (but paying closer than usual attention to brakes & braking) (and of course, don't consume those umbrella'd drinks while driving, since they interfere with cell phone usage).
__________________
Baja-tested '08 2-slide 36'
Alpine: The Ultimate DIY'er Project
EngineerMike is offline   Reply With Quote
Old 09-17-2009, 07:39 PM   #6
Senior Member
 
Join Date: May 2005
Posts: 163
Good suggestion on the tropical resort. We do do this and have less than 50 miles to go, more like 2 blocks to the beach from the FL condo, but that means the coach is in storage for the winter - 4+ months. If I a remote control device I could move it!!!

I hope some other Alpiners file complaints. Bosch knew who was buying their product and how it was used, I was involved in mfg and purchasing too long to know that their excuse doesn't work. Furthermore I will bet Bosch is standing behind Workhorse for the recall costs. The Bosch excuse wouldn't stand up 5 minutes in a court of law!
__________________
2001 36 MDDS
03 Honda Pilot toad
jetar is offline   Reply With Quote
Old 09-21-2009, 11:39 AM   #7
Senior Member
 
Lindenberg's Avatar
 
Join Date: Aug 2006
Posts: 281
EngineerMike - What is the reasoning for driving 50 miles a month?
__________________
Tom & Laurel

2000 Alpine Coach Limited 36FDS
Lindenberg is offline   Reply With Quote
Old 09-21-2009, 12:47 PM   #8
Senior Member
 
Join Date: May 2004
Location: Auburn, CA, Havasu, AZ & Mulege, BCS
Posts: 5,217
First- the coaches that have recurring problems "tend" to be those who set for long periods w/out use. This is not absolute, but is a pattern Bosch &/or Workhorse noted in their investigation. Could be contributory issues of rust accumulation on the rotors, dry spots on pin-slide rusting, or (this was the official explanation but I have a hard time seeing how this works ITRW) water accumulation in the brake fluid that is not driven off by periodic heating of the fluid during normal operation (I can't visualize where/how this water escapes from the caliper bores where the swelling of the Bakelite takes place, but whado I know). So the 50 min. per month de-rusts the rotors & exercises the brakes.

Second, because of the specified destination, even if your brakes give you a hard time, you wind up w/higher quality of life visiting tropical resort destinations and the hassle of the brake issues fades to insignificant after the 8th or 10th umbrella.
__________________
Baja-tested '08 2-slide 36'
Alpine: The Ultimate DIY'er Project
EngineerMike is offline   Reply With Quote
Old 09-21-2009, 01:48 PM   #9
Senior Member
 
Alpine Owners Club
Join Date: May 2008
Location: Vancouver, WA
Posts: 2,226
EM - What is conisdered "late model"?

Now with that said, I'm sure there is maintenance needed on the Meritor Brake units? Does the manual say what that is?

My coach is only two years old, it sat quite a bit on the lot before purchase and now even sits more than used until later this year. Should I have the brake system power flushed? And what are these pins that need to be lubricated?

Does the coach have to leave the ground, or be raised up so the wheels come off on the front or rear? If that has to happen, I don't have the equipment or location to work on it now. I will have to pay someone to do it. Thank you in advance
__________________
Monty & Janet - 2007 Alpine APEX 40 MDTS
S/N - 75715 - Retired - Master Certified RV Tech
Old Rv'er is offline   Reply With Quote
Old 09-21-2009, 04:08 PM   #10
Senior Member
 
Join Date: May 2004
Location: Auburn, CA, Havasu, AZ & Mulege, BCS
Posts: 5,217
Monty- I use the term "late model" in reference to the particular subject matter, so for brakes it would be those using the later brake configuration. I.e. Meritor 4-piston calipers with the HydroMax mounted ahead of the firewall in a left-right orientation constitutes the latest model setup. Earliest had the Hydromax under the driver's seat by the steering gear. There was one model change having to do w/return spring for the brake pedal if my ordinarily lousy memory isn't stuck on its usual scramble setting.

Meritor maintenance- I didn't see regular lube req'mts in the manual, but I wasn't looking. Gerry Smith tells me he had his lubed and eliminated some noise.

Your coach was a 2006 build, so fluid in the system is 3 years old. Time for a flush. Shouldn't go more than 2 years on a system that has to stop 15+ tons. Brake fluid pulls water out of the air and water drops the boiling point of brake fluid. Most of the quality degradation is done in the first 18-24 months, hence my recommended interval of yearly but not more than 24 months.

You don't have pins to lubricate, that is on the Bosch 2-piston, Pin-slide brakes in the earliest coaches (1997-2000 or so, maybe somebody can pin down the model year change on that?).

Its hard to do a full brake check w/the wheels on, though you can do a full brake bleed w/them on. Maybe w/a borescope for the inspection?
__________________
Baja-tested '08 2-slide 36'
Alpine: The Ultimate DIY'er Project
EngineerMike is offline   Reply With Quote
Old 12-12-2009, 12:38 PM   #11
Senior Member
 
Join Date: May 2004
Location: Auburn, CA, Havasu, AZ & Mulege, BCS
Posts: 5,217
There is a Workhorse Technical Document on their Bosch pin-slide brake recall in this thread. This issue may or may not affect early model Alpines w/the Bosch pin-slide brakes (see above in this thread & below for further discussion). The document discusses the actual brake mechanics and source of their current recall problem. Early Alpines may experience this problem, but there is no coach manufacturer to perform a recall. Whether NHTSA would extend recall liability to Bosch itself for brands with defunct coach mfgr's is entirely speculative and at least dependent on whether there are complaints and/or accident reports. Also, Alpines used the larger 73mm piston calipers of similar design; whether 73's are found to act the same as the 66's is yet to be resolved.

I expect as a ratio that Alpines will experience less stuck calipers than Workhorse's gas engine fleet due the prevalence of the PacBrake feature on early WRV rigs. However the extreme importance of regular brake fluid change cannot be overlooked. And if anybody is changing or considering changing brake calipers, IIWMI'd wait to see if the new Bosch design (apparently now in manufacture for the 66mm calipers but not yet available on the street till some time next year) addresses this problem in the 73mm calipers used on Alpines. This new 66mm design should address the sticking of the phenolic piston in the caliper. Nothing will address accumulation of moisture in brake fluid outside of regular brake fluid change (I'd suggest every 12 months on all Bosch equipped rigs).

Also in the above thread link you will find a Workhorse document on mountain driving. The document is written for gas engine rigs, and mostly for those w/out any additional form of drive-line brake feature (PacBrake, Jake, or transmission grade brake). However it is very useful as a starting point for anybody driving a big motorhome safely down steep grades.
__________________
Baja-tested '08 2-slide 36'
Alpine: The Ultimate DIY'er Project
EngineerMike is offline   Reply With Quote
Old 02-06-2010, 10:26 AM   #12
Junior Member
 
Join Date: Feb 2010
Posts: 6
Engineer Mike:
Where is a good reliable place to take my coach to have the break system bled?
Thanks,
George
__________________
GSMcDowell is offline   Reply With Quote
Old 02-06-2010, 01:16 PM   #13
Senior Member
 
Join Date: May 2004
Location: Auburn, CA, Havasu, AZ & Mulege, BCS
Posts: 5,217
I see you are in Michigan, and haven't a clue about the mid-west. Hopefully others in the clan will chime in on other locations.
If you have the Bosch brakes discussed here, any Workhorse center that is equipped to do brakes has experience (probably a lot of it) bleeding Bosch brakes, as their 66mm disc brakes are under a substantial recall involving 50,000 rigs.

On the west coast, I'm familiar personally or by well known reputations w/the following (listed north to south):
Brazel's Centralia, WA
Guaranty RV Junction City, OR
Carrier & Sons , OR
Henderson's Line-Up Grants Pass, OR
Sacramento Truck Center Sacramento, CA
Colton Truck & RV Colton, CA
Redlands Truck & RV Redlands, CA

You can google any of those for more particulars.
BTW, welcome to iRV2 and hope to see you around regularly. Also, you can add your coach data, location, and a smattering of meaningless hubris to a "signature" that will appear automatically at the end of all your posts using the UserCP feature at the top left of the page so folks will get to know you and your rig better without having to explain it each time you have an inquiry.
__________________
Baja-tested '08 2-slide 36'
Alpine: The Ultimate DIY'er Project
EngineerMike is offline   Reply With Quote
Old 02-06-2010, 03:28 PM   #14
Senior Member
 
Refuse1's Avatar
 
Alpine Owners Club
Join Date: Dec 2009
Location: Des Moines,Iowa
Posts: 222
E Mike,

In an earlier post (9-12-09) you stated that the brakes can be bled with the wheels on. That is contrary to other posts I have seen that state that the wheels must come off to get to the outside caliper. which is it?

Thanks,
__________________

__________________
2001 Alpine 36MDDS
Refuse1 is offline   Reply With Quote
Reply



Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
SFT Full Slide Operating Tips LewF Monaco Owner's Forum 7 07-14-2009 10:27 AM
Full Wall Slide Top Awning Problem Lukeaa Monaco Owner's Forum 27 05-19-2009 10:34 PM
Newmar Rear Slide Rollers fsowerby Newmar Owner's Forum 2 05-17-2009 08:20 PM
Slide topper woes...adjustment needed? Boris and Natasha Winnebago Industries Owner's Forum 8 08-28-2008 04:15 AM
Demco Glide Ride Pin Box Notice! wrongway Excel Owner's Forum 14 01-25-2007 08:22 AM

» Virginia Campgrounds

Reviews provided by


Copyright 2002- Social Knowledge, LLC All Rights Reserved.

All times are GMT -6. The time now is 01:01 PM.


Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2017, vBulletin Solutions, Inc.