Do you trust the Oil Life System w/Full Synthetic oil? In this case either 2001 LS1 & 2002 3800 Camaro. My assumption is that it is calibrated for conventional oil and it states that it does not detect particulates. The wild card could be the quality of the oil filter and how well it hold up and continues filtering... So what is the recommended approach when using full synthetic? How many more miles can you go? The change oil light came on around 4k mi. this time.

 

When using full synthetic, you don't pay attention to the life monitor which is based on conventional oil, go by the odometer. Conventional oil starts its viscosity breakdown almost right away, synthetic goes a lot longer before it breaks down. With combination driving (city/highway) there's nothing wrong going 6k miles between synthetic changes. I'd also take the color of the oil into consideration to decide how spent it looks.

 

The color is pretty challenging to use as a determinant - very subjective if you ask me.
In my immediate case, the usage is ~75-80% city driving.


Also, when using full synthetic oil, what oil filters are you all recommending for longer intervals?

 

Oh really. If you have say 5k miles on the oil and it looks almost as clean as the day you put it in, what would you determine from that?

 

i would stay away from anything that doesnt claim that it was designed to be used for an extended drain

I gave this little study a lot of weight when considering which filter to use, maybe you have seen it
Oil Filter Comparison Study - GM Truck Central

I am in the process of extending my drain interval and so far i have gone 7,000 miles with the all clear from the oil analysis company i send my oil to

 

I use Mobil one or Royal purple filters. The main thing is to avoid the low end ones. They are all pretty much made on the same line with the same specs.

Color is a tuff one because as the motor ages you get more blow by and that will darken it oil faster but a good filter makes sure you are not getting any build up. GM policy on oil color was simple, it does not matter. If a new car owner complained that oil was dark after only 500 miles after an oil change the response was, “that is normal”.

How you drive plays a big part as to how often you change your oil. I do 6-7K but that is all highway miles right around 2500 RPMs the whole time. If you used an hour meter (which is how it should be done) I put 60+ miles per hour. That is a little less than 120 hours of running between oil changes. Let say I was averaging only 35 MPH you would be closer to 4000 miles between oil changes.

Going by hours is a lot better then miles. I wish cars had hour meters instead of odometers. It is a much better way to think about your motor. I know guys that drive ½ the miles I do but through Philly every day and I would bet they put twice the hours on their motors compared to me.

I use the 120 hour with a constant speed in clean air. If I had a lot of stops and starts, if I pushed the car hard in the heat, if I was driving dirt roads or if I was towing (yea right in a unibody) I would most likely drop the 120 to 100ish. I am very conservative I am sure you could put more hours on it without hurting anything.

 

Synthetic oils do not break down as fast as the ones made of dinosaur pee, but both collect particulates at basically same rate. So if you plan to go for extended periods before changing your synthetic oil, you need a top of the line filter to get rid of the abrasive stuff before it slowly grinds up engine parts. I go about 5K miles between changes but is mainly highway mileage with most trips over 45 minutes, which gives enough time to boil off all condensation from inside the engine.

 

in cars I drive with regularity (doesn't count the racecar that gets an oil change after every race)

I've always sent samples at varying mileage to Blackstone Labs to have my oil tested to see when it officially breaks down. May be something you want to look into if you don't trust it

 

Thanks for the inputs guys. Gorn's hours tracking makes a lot of sense, as does his color comments, hence my reservation on color alone.

Of late I have been using either AC Delco or Purolator (SuperTech too but they seem discontinued now) and don't usually buy extended life filters, but that I may change that. The thing about filter studies is if it is not current, it may not be accurate, some of the rebranded filters change manufacturers year to year, and that study is from 2011 v64thgen posted. This is another reason I can't wait for a new car that has the permanent oil filter container and I just change the media -- at least it will not be so hidden as it is in cans today!!!

The 3800 wants 10-W30 preferred in the Owner Manual but I have been recommended the 5W-30 year round by a mechanic. On the flip side the LS1 recommends 5W-30 year round. Both with minor exception due to temperatures.

I erred on the side of caution and just did the RS oil change, also due to this issue:
https://camaroforums.com/forum/93-02...ne-cold-76054/

I had a bit more particulate at the drain plug magnet and on the face of the filter mount than usual.

 

It would be great if you could share some results with details about mileage, oil used, filter used and driving style... We may learn a few things.