Originally Posted by mcgrosjr
I have a 2005 Georgetown 325s with a Ford v10 and a Onan Marq Gold 5500 gen, I used to run 10-w-30 in v10 and hd30 in gen but now I run 15-w-40 in both. I am questioning this again because I hear so many different applications, by the way I live and frequent South Louisiana so it is hot most of the time. What do you run in this type of application? Thanks in Advance! mcgrosjr
Use what the manufacturer suggests.
I wouldn't run 15w40 in anything but a diesel.
Most likely 5w30 in the v-10 and 10w30 in the gennie.