[twenty5719]

So I have a 2011 Terrain and I have a question. How often do I get the oil changed?!?!! I do mostly highway driving - 150 per day (125 hwy) - I'm not sure if that effects it or not. My problem is I thought it was every 3500 miles... but then I heard more like 5500-7000 since I probably have synthetic. OnStar sends me the diagnostic report monthly and says I don't need to have any maintainence until I hit 14000 miles!! I know that can't be right, but I am assuming it is adjusting because of the oil life/miles driven already.

OnStar states no maintenance required - in their maintainence schedule it says this:
"Maintenance I Service Package
• Perform when Change Engine Oil light comes on or within
10 months since vehicle was purchased"

If I still have 55% oil life what do I do?

Any and all help would be great.

 

[rutger1413]

If you read on the site you will find a TON of information on oil change intervals and such. General consensus is that you SHOULD NOT go by the oil life monitor. 5,000 - 7,000 is about what most of the DIY group in here go by.

Now this is assuming you are using full synthetic or a synthetic blend. Regular oil should be done at a sooner interval.

There are more complicated responses to this, but please search and read the other threads to get a complete understanding if that is what you are looking for.

 

[GARYD]

:ditto:

If you don't know for sure what's in it, change it at 1k if it is the original oil. After first change, I'd go with full syn and change at aroud 5k to 6k miles.
Personnally, I do not go by the OLM, some have more confidence in it.
I've been changing my own oil for over 50 years and I'm starting to believe the old addage "You can't teach an old dog new tricks". ;D

 

[dwendt44]

With the I4, oil changes seem to be more important to do at reduced intervals.
The problems with Direct Injection, particularly on the I4, result in at least some fuel in the oil.
While highway miles are easier on oil generally, I'd still think about changing oil at 4000 to 5000 miles.
A brand name synthetic and a quality filter should last you 'till the 5000. But keep a close eye on, as in smell for,
fuel dilution.
A 'gassy' odor on the dipstick or at oil change time means talk to the dealer, and shorten the miles between changes.

My 2¢