How reliable is the "change oil" indicator?
 

I use a Valvoline synthetic blend and it's been about 4500 miles or so since I changed my oil. I reset my indicator at the time of the oil change.

I'm just asking, because it seems to be taking longer this time than last time. Should I go ahead and change the oil or wait for the indicator?

if u change a little early,when u feel like it, on a day its not raining??, it mite cost u a hundred bucks xtra in 120,000 miles,sooo,,,just du it! best way to waste money.

i ignor the "computer"

I have a cousin who's a mechanic at what used to be our local Hummer dealership and he says that they'er real accurate. It's funny because I asked him the same question a couple of years ago. The synthetic especially seems to go a long way.

I used to do it as I felt necessary because the time frame started to make me nervous waiting for the computer. Since then I have read posts from a number pf people I consider knowledgeable here and elsewhere that all say they go by the computer. At the very least, if anything happens you followed manufactuers recommendations.

Mine goes off at 7500 miles in my 08 Alpha. I keep a log of all oil changes but stick to the 7500 mile theory with full synthetic Amsoil. Never had an issue with the sensor or onstar calling me to tell me its time to change the oil. I change the oil in my mower daily though. I bought six quarts to see how long it would last and taking a little less than half a quart I figure I am good for the duration.

Mine always says it is time between 7500 and 7900 miles, I use Mobile 1 with the AC Delco Filter.

Thanks guys. I'm not used to my vehicle telling me when to change the oil. I've always followed the 3k/3mo rule and used conventional oil since it was the cheapest.

I decided to use a synthetic blend this last time, but I think when the change oil light comes on finally, I will switch to a full synthetic due to how long this blended oil has been working.

Great informative thread, something I had been wondering about. I didn't keep my H3 long enough for a single oil change - I was waiting for the oil change light to come one, but traded it for the T it after 4k miles of ownership. Our Avalanche (that we just got rid of a few days ago) had oil life % vs. no feedback and an eventual change oil light on the 3/T. I'll wait for the oil change light and use synthetic.

Carefull when changing from normal oil to synthetic!
The synthetic oil has a better cleaning effect and if there is some residue somewhere sticking inside your motor it may loosen with changing to synthetic oil what then can result up to a motor damage!
Ask your dealer for advice!
The risk increases with more miles driven on normal oils...

Guys there is no sensor and the computer doesn't know if the oil is synthetic or not. The oil change light comes on based on a computer computation based on how the vehicle has been driven since the last reset. There's a good read here: http://assets.cobaltnitra.com/teams/...145efa6b30.pdf