How reliable are the oil monitors on GM cars?

I use them on my small fleet and I trust it. 02'Impala 3.8,03'Tahoe Z71 5.3, 08' Impala 3.5, 15' Traverse 3.6, 15' Caddy XTS4 Platinum Vsport. Most hover around 5 to 6K miles when due

Usually change around 10-15% remaining. The older ones might get run with the light on for a bit, but not long.

 

Well you know what they say, when all else fails, read the directions lol -

 

I hit 8,000 km on my GM or Ford and they both still say 30-40% left.

 

I’ve gone by the monitors on my last 3 company pickups. All had 230k- 250k miles when they were turned in. Always Mobil 1. Some went over 10k and and few as 5k before the light came on. We have never had any engine issues (knock on wood). And I’m not exactly “kind” to the company truck....

Let the car warm up (even for 2 miles) and use good oil. The monitor will do the rest.

 

Yes it has an algorithm that looks at many factors, including short drive cycles and idle times.