Oil changes

[Rapidz]

The Ford garages naturally say change your oil evey 3,000 miles in the Diesel. I've heard some of the newer rigs' manuals say 5,000 to 7,000. Is that true?
I'm a stickler for changing the oil when needed. Any thoughts?
Rapidz

[BroncoHauler]

From the 6.0L Diesel Supplement (3rd printing)

Maximum oil change interval
? Normal schedule: 7,500 miles (12,000 km) or 6 months, whichever occurs first.
? Special Operating Conditions: 5,000 miles (8,000 km), 6 months or 200 hours of engine operation, see appropriate schedule.



SPECIAL OPERATING CONDITIONS
Towing a trailer or using a camper or car-top carrier [Every 5,000 miles (8,000 km) or 6 months]

Extensive idling and/or low-speed driving for long distances as in heavy commercial use such as delivery, taxi, patrol or livery [Every 5,000 miles (8,000 km), 6 months or 200 hours of engine]

Operating in dusty conditions such as unpaved or dusty roads [Every 5,000 miles (8,000 km) or 6 months]

Short trip in cold operating conditions [Every 5,000 miles (8,000 km) or 6 months]

[Ford_6L_E350]

My van never sees short trips. It is really only used to travel. So, I see no problem running 7500 miles between changes.

The same engine in International trucks goes 10,000 miles between changes.

With 7500 miles oil changes, I chose to use synthetic 5W-40 oils.

Mike

[Rapidz]

Thanks for the info. After 3,000 miles the oil in my 350 Ford Diesel looks really good.
Rapidz

[WVvan]

Consumer Reports [...] released the results of an extensive test on oil brands and oil changes, as well as other issues regarding car care. In the process, the test demolished much of the conventional wisdom regarding car lubrication. The two most surprising results: the frequency with which oil is changed doesn't matter after the first few oil changes on a new engine, and the type or brand of oil used can not be shown to make any difference.

The testers placed freshly rebuilt engines in 75 New York taxis and then ran them for nearly two years, with each cab racking up 60,000 miles, placing different brands and weights in different cars and changing the oil at 3,000 miles in half the cars and 6,000 in the other half. At the conclusion of the test period, the engines were torn down, measured and inspected. The conclusions: Regardless of brand of oil or weight, no measurable differences could be observed in engine wear. Furthermore, there was no difference among cars which had oil changed at the shorter or longer interval.

In July 1996, Consumer Reports published the results of a two-year motor oil test involving a fleet of 75 New York taxi cabs and found no noticeable advantage of synthetic oil over regular mineral oil. In their article, they noted that "Big-city cabs don't see many cold start-ups or long periods of high-speed driving in extreme heat. But our test results relate to the most common type of severe service - stop-and-go city driving." According to their study, synthetic oil is "worth considering for extreme driving conditions: high ambient temperatures and high engine load, or very cold temperatures."

[daveb]

I think diesels are a different story though. I use AMSOIL and twin filters and still replace the oil at 7K. I do feel any good synthetic will do. But at work our fleet trucks use oil tests and standard Delo oil. Most go about 10 to 12K before changes. The testing system seems to work fine.

[joey2cool]

Originally Posted by BroncoHauler

From the 6.0L Diesel Supplement (3rd printing)

Maximum oil change interval
? Normal schedule: 7,500 miles (12,000 km) or 6 months, whichever occurs first.
? Special Operating Conditions: 5,000 miles (8,000 km), 6 months or 200 hours of engine operation, see appropriate schedule.

SPECIAL OPERATING CONDITIONS
Towing a trailer or using a camper or car-top carrier [Every 5,000 miles (8,000 km) or 6 months]
...

Ford's owner manual for gas vans has the same basic requirements for oil changes as the diesels do. My dealer thought I was being too cautious when I insisted they treat my van according the the SPECIAL OPERATING CONDITIONS - specifically for HEAVEY LOADS (see above). Although the manual only cites towing and car-top carrier examples, I think the 3,000 plus pounds added for RV conversion qualifies. The main thing for me is u-joints inspection and lubrication every six months along with oil changes.

[LenS]

Vehicle out of factory warranty period.

Mobil I 5w-30
Gasoline engine
12k miles or once a year which ever comes first.

Vast majority of miles are highway miles.