ULSD Fuel additives

[Pete Masterson]

Try to get some info about the recommended service interval for your engine. Diesels do not need oil changes as frequently as do gasoline engine vehicles. 

The manual that I have with my DD Series 60 suggests oil changes at 1 year or 15,000 miles. (With a filter change, it takes 40 quarts!) The DD Series 60 manual also suggests that using 1 qt per 1000 miles is "normal." (I actually do quite a bit better than that.)

Since you have a Cat 3208, I'm sure the manufacturer recommendations may be different, but 6000 to 9000 miles on the oil is probably not unreasonable. I'd change the oil at least once each year, no matter what the mileage. It might be best to plan the oil change just before putting the coach "away" for the winter.

Oil test samples are usually obtained at the time you change the oil. It's hard to make any specific determination about an engine based on an isolated (one-time) oil analysis. Generally, you need to make repeated analysis from the _same_ laboratory so you can see trends in the chemical composition. Of course, if you're about to have a catastrophic failure, and oil analysis might warn you ... but then a few more miles and such a failure will become self evident anyway. (If I sound less than enthusiastic about oil analysis, well, it's because, I'm just not sure what use it really is.)

I will observe (in my days working for a railroad) that the diesel locomotives had their oil tested regularly with a liquid chromatography system. The analysis was used to determine what additives to add to that particular locomotive's engine. Oil was almost _never_ changed -- only chemically treated to bring it back into spec. Of course, the locomotives generally had 200 _gallons_ of oil in them, so oil changes would have been incredibly expensive -- it was cheaper to modify the oil with chemical additives. But that's not the case with _only_ 21 quarts -- or even the 40 quarts I have to deal with.

Pete Masterson

'95 Blue Bird Wanderlodge WBDA 42

El Sobrante CA

"aeonix1@mac.com"

On Jun 10, 2008, at 12:44 PM, bubblerboy64 wrote:

In this same vain.  I have had my FC for one year now.  I've put 6000 

miles on the oil and filters. I've got some drips of oil and I likely 

burn some as well. In that one year and 6000 miles I would guess I've 

added at least 5 qts of oil (maybe more) .   Typically I would change 

oil and filters at this time but the ole girl holds 21 quarts.  I do 

next to no short runs and the oil as visible on the dip stick looks 

clean (for a diesel) I am thinking of waiting until winter and 

changing oil before I put her away.  I might run her another 3000 

miles to that point.  I would not want to give her anything but the 

best but it seems in this situation a waste to me. My heart is not 

set on this so if you fellows with experience think I should go ahead 

and change oil at this time I would certainly do so.  It just seems 

like a bit of over kill considering all the "new" oil added and the 

use for which this bus is put.  I know this is asking for opinions. I 

just don't want to be wasteful. Or should I have the oil sampled?  If 

so how do you get a sample? I can see crawling under there and trying 

to get a couple ounces and getting the hole 21 quarts on the drive. 

Or will the truck service centers do this for me? 

John Heckman

central Pa

1973 FC