This report is from my '92 YJ trail rig. I am still running the oil and only sent in a sample. The oil filter is a Motorcraft FL300. I had a light wheeling season this year due to the passing of my brother back in April. I really didn't get out on the trails until summer and have only been on three runs. The rest of the mileage is from joy rides around central/western Mass and hauling the Kayak to the lake every weekend. The sodium (and silicon) from last years UOA was thought to be from the salted/dusty New England dirt roads that lead to some of the trail heads. I'm usually the "tail gunner", so I really get all the dust. I'm very pleased that it has cleared up.
Blackstone's report:
Sodium all but dropped out in this sample. We are no longer worried about a coolant leak. Thanks for the note about the type of operation that this engine sees. The low speeds and idling explain the trace of fuel we found, which is hardly a problem. The fuel lowered the viscosity slightly but this oil has obviously been working well for you so the low vis isn't a problem. No other harmful contaminants were found. At 42,000 miles wear looks great and reads well below universal average levels. We think you could easily run this oil another 2,000 miles.
EQUIPMENT MAKE: Jeep
EQUIPMENT MODEL: 2.5L 4-cyl
FUEL TYPE: Gasoline (Unleaded)
OIL USE INTERVAL: 1,144 Miles
OIL TYPE & GRADE: Castrol GTX 10W40 (SL)
MAKE-UP OIL ADDED: 0 qts
------YJ--Universal Avg.
ALUMINUM 2 3
CHROMIUM 0 1
IRON 4 28
COPPER 2 4
LEAD 1 2
TIN 0 0
MOLYBDENUM 33 43
NICKEL 0 1
MANGANESE 0 0
SILVER 0 0
TITANIUM 0 0
POTASSIUM 0 1
BORON 1 6
SILICON 7 12
SODIUM 2 8
CALCIUM 1479 2398
MAGNESIUM 3 32
PHOSPHORUS 646 844
ZINC 730 1032
BARIUM 0 0
SUS Visc @210*F 62.8 65-76
Flashpoint 370*F
Fuel TR Should be Antifreeze 0.0%
Water 0.0%
Insolubles 0.3% Should <0.6%
Blackstone's report:
Sodium all but dropped out in this sample. We are no longer worried about a coolant leak. Thanks for the note about the type of operation that this engine sees. The low speeds and idling explain the trace of fuel we found, which is hardly a problem. The fuel lowered the viscosity slightly but this oil has obviously been working well for you so the low vis isn't a problem. No other harmful contaminants were found. At 42,000 miles wear looks great and reads well below universal average levels. We think you could easily run this oil another 2,000 miles.
EQUIPMENT MAKE: Jeep
EQUIPMENT MODEL: 2.5L 4-cyl
FUEL TYPE: Gasoline (Unleaded)
OIL USE INTERVAL: 1,144 Miles
OIL TYPE & GRADE: Castrol GTX 10W40 (SL)
MAKE-UP OIL ADDED: 0 qts
------YJ--Universal Avg.
ALUMINUM 2 3
CHROMIUM 0 1
IRON 4 28
COPPER 2 4
LEAD 1 2
TIN 0 0
MOLYBDENUM 33 43
NICKEL 0 1
MANGANESE 0 0
SILVER 0 0
TITANIUM 0 0
POTASSIUM 0 1
BORON 1 6
SILICON 7 12
SODIUM 2 8
CALCIUM 1479 2398
MAGNESIUM 3 32
PHOSPHORUS 646 844
ZINC 730 1032
BARIUM 0 0
SUS Visc @210*F 62.8 65-76
Flashpoint 370*F
Fuel TR Should be Antifreeze 0.0%
Water 0.0%
Insolubles 0.3% Should <0.6%
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