Back to the extended oil drain interval thingie again, some new information ....
Shell Oil achieves INDEFINITE oil drain interval: Shell Oil has utilized GCF By-Pass filters and the GCF P/M Program on their engines within the Gulf of Mexico for over eight years. After two years of rigorous testing and extending oil drains further and further, Shell Oil now only performs an oil drain when laboratory analysis deems it necessary. Some of their equipment have not had a “routine” oil drain in over eight years. Shell personnel now service By-Pass filters and sample their equipment with the portable oil analysis units on a routine basis. Complete laboratory analysis is performed on a quarterly basis. Extending lube oil drains by the use of UF By-Pass filters and this P/M Program has streamlined their lube oil maintenance operations, drastically reduced their downtime, and shown dramatic savings on new oil purchases and disposal cost of waste oil.
http://gulfcoastfilters.com/understanding_lube_oil_and_its_j.htmSource of this tidbit comes from the following Gulfcoast Filters source, a bypass filter mgf who is pushing the boundaries on oil life through better filtration, removing all the soot which Retread mentioned as the source for his oil requiring 10,000 mile replacement.
Interesting that oil analysis equipment is now hand-held, wonder how much it costs to purchase these days.
BTW, THE USA ARMY believes in infinite oil life now, and tests rather than replaces by rote.
Things can sure change on you when your back is turned, count on it.
NAME: Jeff
LEAD FROM:
DATE:
UNIT ID: JEFRN#1
COMPANY:
NOTES: CAT C15 in Western Star
10-7-03- Miles 319366 (copy not mailed) everything normal.
11-18-03 Miles 330,850, mailed copy.
1-30-04- Received report, mailed copy, normal.
2-25-04- Rec’d report, normal, Miles 361,000
3-12-04- Rec’d report, normal, miles 370,481, mailed copy.
4-20-04- Rec’d report, normal, miles 380,490, mailed copy.
5-14-04- Rec’d report, normal, miles 390,056, mailed copy.
6-22-04- Rec’d report, normal, miles 400,302, mailed copy.
8-1-04- Rec’d report, normal, miles 412, 000, mailed copy.
8-18-04- Rec’d report, normal, soot at 0.3, miles 420,231, mailed copy.
9-21-04- Rec’d report, suspect coolant leak, high copper high sodium, Jeff is suppose to take truck to Cat dealer to try and find problem, Changed OIL – 1st in 430,000 miles!!!!!!!!!!!!!11-17-04- Rec’d sample, 1st since engine was repaired for coolant leak. Sample is normal, soot at 0.0. Mailed copy.
12-13-04- Rec’d sample, normal, soot at 0.2, mailed copy.
1-15-05- Rec’d sample, normal, soot at 0.0, mailed copy.
2-15-05-Rec’d sample, normal , soot at 0.2, silicon at 22
3-17-05- Rec’d sample, normal, soot at 0.2, mailed copy.
4-22-05- Rec’d sample, normal, soot at 0.2, mailed copy.
5-19-05- Rec’d sample, normal, soot at 0.2, mailed copy.
This above is "relatively normal results", for best in class on a dino oil see below.
http://gulfcoastfilters.com/1,000,000%20MILES.htm
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