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JCGibson's avatar
JCGibson
Explorer
Jan 05, 2015

Used DP Reliability

In our quest for a Class A our options are a used DP that is about 6 years old or older or a newer gasser. What I would like to know if how the used DP reliability would be. I know it would depend on how maintenance was performed and how often, but even with that systems can and will fail. These items I am most concerned about since I don't have experience with them:

1. How long will the air suspension last before it starts to have problems and what maintenance is necessary?

2. Air brake system. How long do the shoes typically last and are they like the old days when cars had drum brakes and they have to be adjusted periodically, unlike disc brakes?

3. Does the air suspension and brakes use the same compressor system?

4. I am familiar with Cummins since we have one in our Dodge pickup, but what things are there to look for with a Cat engine?

5. Does anyone know if the Cummins in a Class A has the same or similar maintenance requirements as the pickup version?

6. What required maintenance is necessary for the transmission and is there anything to look out for?

7. I usually do most of my maintenance work, is the engine area easily accessible within reason?

8. Is there a chassis/owners manual that has recommended maintenance schedule?

9. Are parts readily available if something needs to be repaired?

10. Anything else I should be concerned with or need to watch for?

I know this is a quite lengthy list, but just want to be prepared.

Thanks everyone. You have been very helpful so far.

John
Class A

16 Replies

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  • Pogoil's avatar
    Pogoil
    Explorer
    Jan 05, 2015
    Reliability, now there is a word. You see problems in brand new coaches as well as older coaches.

    Ours is 20 years old and we have had a hydraulic pump failure. Other issues were minor and all fixable. At 20 years old no leaks from any component on the MH. It is a Beaver and seems to be built well.

    Do expect extra costs as mentioned in filters and larger amounts of fluids. Try if possible to find a unit with new tires or negotiate price based on tires if possible to avoid initial sticker shock at purchase.

    Do your own work and save a bundle plus it is rewarding.

    Pogoil.
  • wolfe10's avatar
    wolfe10
    Explorer
    Jan 05, 2015
    Slobber tube is the open crankcase breather on all diesels before the EPA tightened up specs, after which they all had to go to closed crankcase ventilation.
  • JCGibson's avatar
    JCGibson
    Explorer
    Jan 05, 2015
    oldmattb wrote:
    Brett's advice was what inspired me to do my own maintenance, aside from my just being a cheap-ass. His opinion counts.

    Matt B


    Doing it cheaper and not paying someone else for what I know I can do is my goal. I work on everything else I have; Corvette, Cobra replica, my wife's car and the Dodge pickup.

    One other thing. What is the slobber tube? I have read some comments about that, but have no idea what it is.

    Thank you both for the quick responses.

    John
  • oldmattb's avatar
    oldmattb
    Explorer
    Jan 05, 2015
    Brett's advice was what inspired me to do my own maintenance, aside from my just being a cheap-ass. His opinion counts.

    Matt B
  • oldmattb's avatar
    oldmattb
    Explorer
    Jan 05, 2015
    Do you MIND doing maintenance? Our DP has a two AC filters, an air intake filter, an oil filter, two fuel filters, a coolant filter and three hydraulic filters. There is a lot to keep up with. I rather like the discipline of it.

    We had to order a hydraulic pump from out-of-state. Second day delivery was reasonable.

    Engine access is surprisingly difficult. There is a lot of stuff jammed in there. I recently removed a hydraulic thermostat for inspection. I could see it and touch it. The back bolt required clearancing the part with a hacksaw and grinding a socket paper-thin on one side to get the bolt removed. Probably more a symptom of modern design than DP problem.

    Our air bags are in decent shape after 16 years of use. I plan to replace them this summer as a preventative. Shocks are on the list too - 50K miles according to records, though some look original. Brakes are original and are fine. Previous owner taught me to use the exhaust brake!

    Most DPs will likely come with a maintenance schedule, or one will be readily available. You will always be doing a bit of web search for quantities, methods, etc.

    Matt B
  • wolfe10's avatar
    wolfe10
    Explorer
    Jan 05, 2015
    John,

    Answers in SOLID LETTER CAPS.

    JCGibson wrote:
    In our quest for a Class A our options are a used DP that is about 6 years old or older or a newer gasser. What I would like to know if how the used DP reliability would be. I know it would depend on how maintenance was performed and how often, but even with that systems can and will fail. These items I am most concerned about since I don't have experience with them:

    1. How long will the air suspension last before it starts to have problems and what maintenance is necessary? AIR DRYER SERVICE/REPLACEMENT IS ABOUT THE ONLY MAINTENANCE ON AN AIR SYSTEM. MOST USE THE ENGINE MAIN AIR FILTER RATHER THAN A SEPARATE FILTER.

    2. Air brake system. How long do the shoes typically last and are they like the old days when cars had drum brakes and they have to be adjusted periodically, unlike disc brakes? SOLD OUR FORETRAVEL WITH 170,000 MILES AND STILL 50% OF SHOES LEFT. SURE, IF ONE DOESN'T KNOW HOW TO DRIVE A DIESEL AND DOES NOT USE THE EXHAUST/ENGINE BRAKE, YOU COULD WEAR OUT BRAKES.

    3. Does the air suspension and brakes use the same compressor system? YES.

    4. I am familiar with Cummins since we have one in our Dodge pickup, but what things are there to look for with a Cat engine? NO SIGNIFICANT DIFFERENCE. BOTH CATERPILLAR AND CUMMINS MAKE EXCELLENT ENGINES.

    5. Does anyone know if the Cummins in a Class A has the same or similar maintenance requirements as the pickup version? I DON'T KNOW PU MAINTENANCE, BUT CUMMINS HAS RECOMMENDED MAINTENANCE SCHEDULES IN THEIR OWNERS MANUALS AND PROBABLY ON-LINE.

    6. What required maintenance is necessary for the transmission and is there anything to look out for? ALLISON HAS RECOMMENDED FLUID/FILTER CHANGE RECOMMENDATIONS ON THEIR WEBSITE. BIGGEST VARIABLE IS SYNTHETIC FLUID VS DEXRON.

    7. I usually do most of my maintenance work, is the engine area easily accessible within reason? MORE SO ON SIDE RADIATORS, BUT EVEN REAR RADIATORS PROBABLY NO WORSE THAN MOST GASOLINE C'S AND A'S.

    8. Is there a chassis/owners manual that has recommended maintenance schedule? YES, GENERALLY EACH MAJOR COMPONENT COMES WITH A MANUAL AS WELL AS A GENERAL ONE FOR THE COACH.

    9. Are parts readily available if something needs to be repaired? YES, MOST COMPONENTS ARE COMMON TO TRUCKS AS WELL AS DP'S. SURE, IF OVER 20 YEARS OLD, MAY FIND PARTS SOURCE ISSUES.

    10. Anything else I should be concerned with or need to watch for?

    I know this is a quite lengthy list, but just want to be prepared.

    Thanks everyone. You have been very helpful so far.

    John

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