My dads 05 3500 is using oil. Its also smoking. I just figured it was smoking a little cause it was broken in now at 125K well I drove it today its smoking more than I thought almost as much as my 97 could make and its STOCK. Any ideas on what it could be he said hes also noticed a drop in fuel mileage. But the biggest thing is the oil and smoke. Any ideas?

 

Have a EOA run on oil to see if fuel contimination or wear. Sometimes changing brand of oil will reduce. Don't recall, but does it have a vacaum pump? A vac leak will cause pump to pressurize the crankcase. JMT's

 

How many miles between a quart? What mods done to it?

 

Its stock with a southbend clutch. ill find out about the oil change and quarts added.