Mtngoat,
I am curious about the oil analysis technique as well. The key seems to be getting a good sample from oil that has been well mixed and warmed before sampling. In the Fall 1995 TDR, they reprinted an article from the Sept 1995 "Owner Operator" magazine (big truck mag?). The article was called "Unlocking the Mystery of Oil Analysis" and had a fairly detailed description of the process.
Here are some interesting quotes from that article (I have it right in front of me here):
'Dennis Boggs, Phillips 66 lubricants technical director says, "You can use oil analysis to determine whether or not you are able to increase or must decrease oil drain intervals. That is one of the main purposes of oil analysis. "
But, the Detroil Diesel engine lube requirements manual says, "Since an oil analysis cannot completely assess the lubricating oil for continued service, it should not be used to extend oil drain intervals. " Don Carver, Cummins' wily director of petroleum products, recommends using the company's charts to set your change intervals rather than analysis. He says you can come up with intervals based on analysis, then experience a change in operating conditions, and compromise engine protection before it's even time to use analysis again.
These objections from engine manufacturers offer proof that increasing oil change intervals is a risky business, and must be approached very cautiously. But, don't ignore the need to use oil analysis on a regular basis. A good program pays dividends. '
The article has a sidebar on the "super filters" or what people refer to as bypass filters I guess, the users and test labs reported very good filtration results but the article cites several oil and engine manufacturers who expressed concern since while the super filters removed fine particulates better, there might be problems with sludge buildup on pistons etc from antiwear additives that have given up the ghost over long drain intervals - zinc and phosphorus being singled out.
They list a bunch of different analysis companies, and close the article with a section that is titled "Develop a Program for Extended Drain". Their recommendations were:
1. Use a premium oil with extended drain capability and proven performance
2. Use analysis along with other means of evaulating stresses on the oil, to determine the change interval. It says that over-the-road trucks getting 6. 5 mpg or more with less than 25% PTO and idle time are the best extended drain candidates. Translated to Ram usage, this would likely correspond to a truck that is worked on the road a lot with minimal stop-n-go traffic.
3. Don't take on the risk alone. If under any kind of warranty, get manufacturer approval for extended changes. If the engine manufacturer won't warrant it under these conditions, the oil manufacturer might - but you need to get their approval on the extended drain.
4. Use premium filters. A guy from Wix Corp. said, "Standard filters may not be suitable for extended drain. " He recommended using one of the fiberglass media type filters since they are supported with a metal screen and not as subject to media "blow out" as the standard paper elements.
Number 3 makes you stop and think.
There were several other blurbs on oil in that issue that offer some good advice too. One of the readers had corresponded with the Chief Engineer for the Premium Blue oil that Cummins sells, asking about the use of thinner oils in the CTD, specifically 10W-40. The engineer recommended against it, expressing concern that the 10W-40 would be too thin at start-up, and specifically mentioned that the synthetic oils tested by Cummins tended not to protect the engine at start-up temperatures above about 0 degrees F because of poor adhesive properties. The engineer apparently recommended staying with the oil recommendations in the owner manual as determined by Cummins.
In the next issue, Spring 1996, there was a TDR Review on Oil Analysis where the writer was able to meet with Ms. Shirley Minges from Lubricon Labs, a division of Fleetguard. (This is a great article, it would be useful to the members if Robert or somebody scanned it and put it on the board in the archives. )
Here are some quotes from the article:
'Inevitably our conversation turned to the subject of oil change intervals. She cautioned about using analysis results alone as the basis for extending the interval between oil changes. To explain the logic behind her caution, she agreed to instruct our readers in how to interpret the results of an oil report.
Shirley commented, "If you're considering an extended change interval, at a minimum you'll need three things: the support of your engine manufacturer, the support of your oil company, and a person on staff dedicated to monitoring the conditions between oil changes. Using analysis alone to look at the condition of the lube oil doesn't tell you any more than, say, a picture of a mountain climber. At the time of the picture, the conditions were OK. The next step may have been the one where the climber fell off the cliff. It's the same way with oil. In the next 500 miles the additive package in the oil, which consists of an anti-wear component (zinc, barium, and phosphorus), an anti-foam component (a silicon polymer), and detergents to hold contaminants in suspension (calcium and magnesium) may deplete. You won't know this until the next sample - which may be too late. "
"Further complicating any oil change extension is the addition of oil to keep the oil at the acceptable level. New oil replenishes the existing sump. Depending on an engine's condition, some trucking firms simply continue to add oil to the sump without ever making a complete change. You've got to ask yourself, how did the engine reach a condition which would seem to justifiy such a practice? Chances are it's an old engine or one which has been neglected. "
"For the average fleet, it's best to stick with the manufacturer's advice on change intervals. Oil analysis is best used to analyze trends and to catch a small problem before it turns into a big one. " Let's take a look at what an oil sample can tell you via the typical Lubricon report. ' (. . followed by chart. . )
'It was strongly suggested in Issue Ten's "ShadeTree" article to stay with the published manufacturer recommendations for oil changes. Shirley has the same recommendation: "For the Turbo Diesel engine with its small oil capacity (3 gallons compared to a 11 gallon "big rig" engine and a 50 gallon Cummins 50 liter engine) the oil and filter change is cheap insurance. " "Oh yeah," she adds, "use the Fleetguard LF3552 microglass filter for your Turbo Diesel, it's additional filtration insurance for your engine. " Thanks Shirley!'
Too much typing, fingers hurt
The article concludes with a bunch of info on the different wear metals, their probable / possible source, and "normal" ranges for our type of engines. Really good stuff!
Maybe somebody can scan the chart and the description of wear metals into the computer...
Attention: TDR Forum Junkies 
Are there any other companys that do this a little quicker? 
My sample was completed on the 10th. 
