Forum Discussion

dalenoel's avatar
dalenoel
Explorer II
May 16, 2021

New Serpentine Belt?

With some long trips, 6500 miles, coming up and all the posts regarding serpentine belts I think I should have a spare with me.

I already keep tires less than 5 years, TMPS, Silverleaf for data, fluid changes and test regularly have roadside assistance in case of emergency, and keep extra filters with me but have no idea what size belt to get.

Is it better to measure the one on the coach or to ask Cummins what is needed.

2003 Neptune ISB300, 36'

Thanks for for the help.
  • agesilaus's avatar
    agesilaus
    Explorer III
    May 16, 2021
    If you have the ability and tools to change it on the side of the road then carry a spare. If not why bother?

    You can call an ERS and get them to change it. I have one in the back of the truck I'll get a mechanic to swap out next time we are at the home port. I changed all the fluids and at the 10 year point I fuigured it can't hurt to replace it.
  • monkey44's avatar
    monkey44
    Nomad II
    May 16, 2021
    Just blew an A/C belt sitting in my driveway, idling, at 60K miles. Will replace it now, and add the serpentine belt and regular service. Will save the one off, and carry it with us. We plan a cross-country trip soon, and would be NICE to have the proper belt as a spare, even a temp spare.
  • CA_Traveler's avatar
    CA_Traveler
    Explorer III
    May 16, 2021
    dalenoel wrote:
    Is it better to measure the one on the coach or to ask Cummins what is needed.
    If the labeling is gone take it off and buy the exact same one.

    Cummins may not know what belt you have due to Monaco added equipment.
  • time2roll's avatar
    time2roll
    Nomad
    May 16, 2021
    Roger10378 wrote:
    If you have the ability and tools to change it on the side of the road then carry a spare. If not why bother?
    Sometimes it is easier to find service help than parts. Especially at late hours or holiday etc.

    For the OP: Have the belt changed at your next service. Save the old as a spare. Then you know it fits.
    Generally I believe minimum life on these is 10 years and 100,000 miles. So unless you are approaching that I would not have any concern yet.
  • Roger10378's avatar
    Roger10378
    Explorer II
    May 16, 2021
    If you have the ability and tools to change it on the side of the road then carry a spare. If not why bother?
  • theoldwizard1's avatar
    theoldwizard1
    Explorer II
    May 16, 2021
    If it gives you peace of mind, carry spare. I have NEVER lost a serpentine belt in over 40 years of driving.
  • Dusty_R's avatar
    Dusty_R
    Explorer
    May 16, 2021
    Many years ago a good Ford machanic told me that Ford said not to bother changing the Serpentine belt until ti started loosing rubber from the inside of the belt. Many people worry about them when the stare to crack on the inside. He said don't worry about those cracks.
    I've never lost one.

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