93 Grand Cherokee, 1st 100k original owner dealer serviced every 3k. I have used M1 10W30 since, avg about 5k OCI. It has intake leak since I bought it and have also used K&N replacement filter in stock airbox for the last 100k. Switched to M1 10W30 HM last time so this is second 6k on HM. My first oil analysis on the Jeep. Looks pretty good to me with 209k. Blackstone says go 7500 miles.
MI/HR on Oil 6,155
MI/HR on Unit 209,460
Sample Date 11/22/08
Make Up Oil Add 1 qt
ALUMINUM 4
CHROMIUM 2
IRON 23
COPPER 3
LEAD 1
TIN 2
MOLYBDENUM 77
NICKEL 1
MANGANESE 0
SILVER 0
TITANIUM 0
POTASSIUM 1
BORON 118
SILICON 10
SODIUM 7
CALCIUM 2450
MAGNESIUM 21
PHOSPHORUS 686
ZINC 893
BARIUM 0
SUS Visc 210F 64.3
cST Visc 100C 11.43
Flashpoint F 385
Fuel % Antifreeze % 0.0
Water % 0.0
Insolubles % 0.3
TBN 5.3
MI/HR on Oil 6,155
MI/HR on Unit 209,460
Sample Date 11/22/08
Make Up Oil Add 1 qt
ALUMINUM 4
CHROMIUM 2
IRON 23
COPPER 3
LEAD 1
TIN 2
MOLYBDENUM 77
NICKEL 1
MANGANESE 0
SILVER 0
TITANIUM 0
POTASSIUM 1
BORON 118
SILICON 10
SODIUM 7
CALCIUM 2450
MAGNESIUM 21
PHOSPHORUS 686
ZINC 893
BARIUM 0
SUS Visc 210F 64.3
cST Visc 100C 11.43
Flashpoint F 385
Fuel % Antifreeze % 0.0
Water % 0.0
Insolubles % 0.3
TBN 5.3