Popular Mechanics had an article about the GM Oil Life System. To sum up:
- Works by counting crankshaft revolutions and recording engine parameters such as hot and cold engine temps as well as a number of other
factors depending on the engine
- The purpose of all this is to predict when the ZDDP (zinc dialkyl dithipphoshate) in the oil is exhusted at which point engine wear accelerates.
- Unfortunately the algorithim can't account for a leaky air cleaner, coolant weeping into cylinders, bad gas excess crankcase condensation from a stuck theromostat etc.
- Oil contaninated with dirt, water coolant, bypassed exhust gases or unburned fuel accelerate engine wear.... none of which can be accounted for in the algorithim.
- Mercedes uses a sensor that determines the dielectric content of the oil (a measure of the oils ability to resist electrical fields). As the oil is contaminated with dirt, wear particles water and partially burned hydrocarbons.
It has no bearing on the capacity of the oil to protect your engine
- Works by counting crankshaft revolutions and recording engine parameters such as hot and cold engine temps as well as a number of other
factors depending on the engine
- The purpose of all this is to predict when the ZDDP (zinc dialkyl dithipphoshate) in the oil is exhusted at which point engine wear accelerates.
- Unfortunately the algorithim can't account for a leaky air cleaner, coolant weeping into cylinders, bad gas excess crankcase condensation from a stuck theromostat etc.
- Oil contaninated with dirt, water coolant, bypassed exhust gases or unburned fuel accelerate engine wear.... none of which can be accounted for in the algorithim.
- Mercedes uses a sensor that determines the dielectric content of the oil (a measure of the oils ability to resist electrical fields). As the oil is contaminated with dirt, wear particles water and partially burned hydrocarbons.
It has no bearing on the capacity of the oil to protect your engine