Forum Discussion

joraz's avatar
joraz
Explorer
Jun 07, 2016

LP vs. Gas

I'm thinking about buying another rig (sold ours six months ago). This rig is a GMC (1976) with an Olds 455. It's low mileage and has only run on LP. I've got a couple of questions:

1. Other than it being less efficient are there any negatives associated with running on LP?
2. In that this rig has been running only LP, other than rotted gas line, what other problems might I encounter?

Thanks.
jor
  • dougrainer's avatar
    dougrainer
    Nomad
    Jun 07, 2016
    I have never seen a Motorhome that runs ONLY on LP. Especially a Vintage GMC. They were built on Gasoline and conversions to run Dual LP/Gas were common back then. Are you positive that it has been outfitted to ONLY run on LP? There is NO Gasoline tank? What about the slide drawer 6.0 Onan? Does it run on LP also? The problem with running on LP ONLY is simple---You would need an extremely LARGE LP tank/s to go just 100 miles. That is why dual LP/Gas were the way to go. Doug
  • romore's avatar
    romore
    Explorer II
    Jun 07, 2016
    You may have problems with the heads, engines of that vintage didn't have hardened valves and seats. Valve guides didn't last long either, LP is very dry and caused the oil to break down.

About Technical Issues

Having RV issues? Connect with others who have been in your shoes.24,228 PostsLatest Activity: Apr 04, 2025