Dodge Ram 6.4 Heavy duty V-8 gas
Says premium gas is recommended?.. What is the downside if regular gas is used? Some folks are telling me nothing other than a slight decrease in power?.. Ram dealers in my neck of the woods ar...
Forum Discussion
Mortimer Brewster wrote:
From pg 542 of the manual:
STARTING AND OPERATING 6.4L Engine
This engines is designed to meet all emissions regulations and provide satis- factory fuel economy and performance when using high quality unleaded gaso- line having a posted octane number range of 87 to 89 as specified by the (R+M)/2 method. The use of 89 octane
“Plus” gasoline is recommended for optimum performance and fuel economy.
While operating on gasoline with an octane number of 87, hearing a light knocking sound from the engine is not a cause for concern. However, if the engine is heard making a heavy knocking sound, see your dealer immediately. Use of gasoline with an octane number lower than 87 can cause engine failure and may void or not be covered by the New Vehicle Limited Warranty.
When I run 87, i get the knocking sound and less power. I just end up running 89 all the time. the cost isn't that much more and the engine runs much smoother.
