Originally Posted by Jon_Celia
I own a 2001 Dodge 3500 4x4 with 175K miles on it. I have owned it since new. 12 years now. I have had my Cummins upgraded from Dynamite Diesel over the years. They race their trucks. Lenny (the owner) told me to use dino oil,not synthetic. Diesels add carbon to your oil as they run, so at some point with too many miles, you end up with the oil not doing its job and wearing out your valves.
I change my truck oil more than recommended since I think it is cheap insurance for wear.
I would recommend you google synthetic oils in cummins and see what other people say.
Hope this helps.
I'm running a 2006 Cummins 5.9. Been changing out the dino oil (Shell Rotella T) every 10000 km (6200 miles) since I've owned it. I bought the truck with 61000 km on it 3 years ago, now sitting at 175000 km.
The reason I've went with Rotella T is that I can get it (usually on sale) in a 20 liter pail (truck takes 11 liters) and it's more cost effective to buy the pail.
But by changing out at regular intervals (10000 km) I keep fresher oil going in/coming out of the engine. I'm hoping that it will be cheap insurance to keep the Cummins running for a very long time.
I would like to think that if you didn't do as many km's over the course of the year, somehow someway there is still a way for condensation to get into your engine throughout the year and dilute the oil. My hunting buddy who had virtually the same truck as me doesn't put on the same amount of km's as I do, but still does a spring & fall oil change, whether it hits the km mark or not...
At the price of replacing an engine, I would say that changing oil twice a year (at a minimum) is cheaper; best not to take the risk?
Good luck on your decision.