Forum Discussion

Empty_Nest__Soo's avatar
Empty_Nest__Soo
Explorer
Jun 05, 2013

Diesel engines -- low miles?

I have no experience with Diesel engines.

In reading this forum, I’ve seen a number of cautions regarding potential problems and expensive repairs because of Diesel engines sitting unused too long.

We’re looking to buy our first motorhome and I am attracted to models with Diesel engines. I find a number of Diesel motorhomes in the neighborhood of 10 years old that seem to have been lightly used, maybe only 30,000 to 40,000 miles.

I realize that I want to see service records and make sure that service was performed at the appropriate intervals, etc.

But at what point should I consider the mileage on an older Diesel to be so low as to be a red flag of problems from sitting unused too long? How low is too low?

Thanks!

Wayne
Class A

10 Replies

  • Empty_Nest__Soo's avatar
    Empty_Nest__Soo
    Explorer
    Jun 06, 2013
    Macktee wrote:
    Proper maintenance is definitely the key. Here is the best way to ease your fears. Take a look at the equipment on a farm. Most of them have Diesel engines and yet many only work a few weeks each year. If kept up properly, they don't miss a beat. I know from first hand experience. Macktee

    Makes sense to me. I live in farm country and lots of folks nearby have Diesel tractors, etc., that are used heavily in season and not so much other times of the year.

    I had an acquaintance who had a Diesel auxiliary motor in his sailboat. It was used so little he would buy fuel every couple of years. No problems that I'm aware of.

    Thanks, everyone! This has been very helpful!

    Wayne
  • JimM68's avatar
    JimM68
    Explorer
    Jun 05, 2013
    I would not worry about high or low mileage on a diesel motorhome engine or drivetrain.

    I would more worry bout the coach systems, and the tires.
  • BarbaraOK's avatar
    BarbaraOK
    Explorer
    Jun 05, 2013
    Tires would be a concern. That low mileage would probably mean they sat a lot, which means UV degradation. So plan on replacing the tires. 10 years old, have the belts and hoses checked CAREFULLY. You would be doing that if getting a lot of travel time having normal service but there are a lot of people who go by mileage instead of time for servicing a DP and if only 3-4 K then might only be doing service every 2-3 years instead of every year. Has the refrigerator been checked to see if it was on the recall, etc.?

    Take your time and really look it over. But that is good advice for any rig.

    Barb
  • gatorcq's avatar
    gatorcq
    Explorer
    Jun 05, 2013
    A 3126E, C7 are 300K engines. It seems some people who own MH travel from point A to B. Low mileage.

    The mayor maintenance is change oil every year, fuel filter 1 to 3 years, and air filter every 2 years. And somewhere in the 3 to 5 years change the dryer filter. Speedco Lube and Truck charges less then $200 for lube, oil and fuel filter.
  • ScottG's avatar
    ScottG
    Nomad
    Jun 05, 2013
    The problems with a diesel sitting a long time are associated with the fuel going bad and/or growing algae in it. This can cause all sorts of problems that will arise no matter what kind of maint. the PO did.
    But 3~4k a year doesn't sound to bad and if it has fuel issues you'll either have driveability issues or the filter will keep clogging - which is just an inconvenience IMO (BTDT).
    If it were me, I would take it on a good test drive and if it runs good I'd go for it. If it's rough, cuts out or falls on its face I'd skip it.
  • SCOMP225's avatar
    SCOMP225
    Explorer
    Jun 05, 2013
    Macktee wrote:
    Proper maintenance is definitely the key. Here is the best way to ease your fears. Take a look at the equipment on a farm. Most of them have Diesel engines and yet many only work a few weeks each year. If kept up properly, they don't miss a beat. I know from first hand experience. Macktee

    Nail on the Head !
    Look for one that has Not been sitting for long periods of time. They are built to be used and will have far less issues. If you find one you are hot on I would strongly suggest that you have an Oil Analysis done before the purchase.
  • discovery4us's avatar
    discovery4us
    Explorer
    Jun 05, 2013
    I bought a 1999 DP two years ago with only 19,000 miles on it. My biggest concern over the low mileage units that I saw wasn't the engine as it was the coach itself. Most low mile rigs were not moved and had been lived in and appliances and furniture showed wear. Ask for maintenance records or have a mechanic look it over and enjoy. Also check to see if it has an hour meter along with the odometer. Mine had been in storage but based on the hour meters the previous owner did run the motor and the generator periodically.
  • Macktee's avatar
    Macktee
    Explorer
    Jun 05, 2013
    Proper maintenance is definitely the key. Here is the best way to ease your fears. Take a look at the equipment on a farm. Most of them have Diesel engines and yet many only work a few weeks each year. If kept up properly, they don't miss a beat. I know from first hand experience. Macktee
  • paulcardoza's avatar
    paulcardoza
    Explorer
    Jun 05, 2013
    While some will panic over low mileage, my view is that if properly maintained, there are no concerns whatsoever. Diesel engines can sit for years and then function with no ill effects for many years afterward. AGAIN, proper maintenance is the key.

    If you are presented with a solid set of service records, don't let low mileage concern you one bit.

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