I have read the these motors are prone to sludging. I have the 5.9 with 80,000 miles on it, I have been using Penzoil 10w30 and changing it every 3K to 4K. I am considering what oil would be a good fit to keep the sludging to a minumum and considering a High Milage or synthitic.
I am in Utah so it's cold in the winter and gets up to about a 100 in the summer.
Thanks,
Jeff
I am in Utah so it's cold in the winter and gets up to about a 100 in the summer.
Thanks,
Jeff