I've been trying to adhere to GM's reccomendation of following their Oil Life System. However, I just ticked over 4K miles with no "Change Oil" or such message. In my previous vehicles, I've changed oil every 2500 miles, so I'm itching to drop the oil out. I called my dealer and got his take on it, and he said I'd be better off just changing it like I normally do. I plan on switching to synthetic, changing it every 5K, and changing the filter every 2500.

My question is, does anyone know the parameters that the Oil Life System takes into account? I've heard everything from engine load, to average speed to the number of times that the engine ist started, but I was just curious. Thanks.

-Adrian

 

I use Mobil 1 Extended Performance 5w-30, 15,000 mile oil. 5qt jug from Wal-mart, for about $27, and Wix oil filter from a 4.3, cause it's longer, lets oil flow better, not so packed.
I change my oil every 12,000 mi, and the filter and rotate tires every 6,000mi. Beenrunning syntheticsforalmost600,000 miles, and never had an engine apart, nor one leak. Been running the Mobil 1 EP since it came out. That's when I went to 12,000mi oil changes.
Conventional oil has been around since forever. Step into the 21st century and use todays lubricants in todays vehicles.
My Onstar oil life monitor tells me I should be able to go 20-30,000 miles between changes.
Hope this helps.

 

wayne you seem to know what your talking about when it comes to synthetics. sorry to throw this thread off topic but is there anything i should know if i'm going to switch to synthetic? i've heard things about having to change your oil again in a shorter period when switching as the transistion makes the oil get dirty faster till you run it through a few times..

 

I always flush the oil system before switching motor oil, unless it's new.
I don't synthetics in my trannys, as I haven't seen the difference. Trans' don't have combustion gases to deal with like the motor does, nor have I seen any manufacturer make any major claims nor warrantys. I DO believe that they are every bit as good or maybe even better than Dextron III, but NO service tech had EVER tried to convince me that there is something better, unlike synthetic motor oils.
I personally believe that Royal Purple is the best motor oil out there, but they don't have a warranty. Fact is, NO BODY does but Mobil 1. I use their 15,000 mile product. Doesn't make cents to me not to.
I rotate tires every 6,000 mi, and that determines the frequency of oil and filter changes.
FYI: the Chevy dealer charged me almost $13/qt on the last filter change! Not again!

 

http://www.quakerstate.com/pages/programs/warranty.asp

 

So Quaker State says there oil is good for 4,000 miles WOW!. I'll stick with my 15,000 mile Mobil 1 EP oil, thanks.
But thanks for showing me that Mobil isn't the only company with a warranty, but there's is strict.
Are there any others? Any with a better warranty than Mobil? Is so, I'd be interested in trying it.
How 'bout trans' fluid?

 

good full synthetics are good for 10, 20 and some evern 30k miles.

It really depends on the type oil and driving condtions.

The oil life monitor makes an estimation based upon driving conditons, driving styles and various engine factors such as O2 sensor, MAF, MAP and IAT readings. It also knows the difference between stop and go traffic and crusing on the highway. For the most part its farily good and very conserative if using the type and grade of oil reccomended in the manual.

If your looking to maximize your oil life it really has abslotuly nothhing to do with number of miles. A more accurate measurement would actually come from number of hours your engine runs. The key factors for oil life are particulate counts and acidity (known as TBN). What is done in commercial applications (and what I do for the first year I own any car or truck) is I get a few oil analysis kits and send samples in at measured intervals. After a few cycles I can come up with a degradration curve that I use to estimate oil life. On a broken in engine (30-50k) using good synthitic (I use AMSOil) I go between 15,000 and 20,000 miles on average. On a newer engine its important to check more regularly as your cam(s), crank and other metal wear components will give off higher levels of metals as they settle in.

If you are using dino oil I wouldnt go more than 4-5k miles as the organic nature of the oil tends to result in higer acid levels very quickly even with modern acid inhibitors.

Finally get a GOOD filter, even if using cheap oil, your filter is the best way to protect your engine. Aside from acid, metal particles will wear on moving parts and can create long term damage. Make sure you have a good filter that filters out particles measured in microns and even when running oil for long periods (8k or more) change the filter at regular intervals (I change my filter ever 5-7k). Be sure to check the flow rate as well, some filters have really great filtering properties but do so at the cost of flow pressure. Low oil pressure can cause all sorts of problems.

In any case oil intervals of 2500 or even 3000 miles are antiquated and based on assumptions from almost 30 years ago. Technology has changed much since then. Unless of coure you are using the JiffyLube special oil, that crap isint fit for any modern engine and barely qualifies as oil.

For more information see: http://www.bobistheoilguy.com/

 

We've had great oil threads here.

The general concensus isthat no matter if you you use dino or synth, alow-life oil filter will negate all your efforts.

Hope this helps.

 

OK, so what brand filters are good? I used to strictly use Fram, but now I hear that they are not any good, so what should I use?

Thanks,
John

P.S. My SS purchase has been delayed, I was actually able to sell my trade-in this weekend, so I'm taking care of that first, and looking at a couple of other SS's before I make the final decision.Got a lot more for the sale than the trade-in price, so that helps too...

 

I typically use K&N or AMSOil

What you are really looking for is some preffered desgin properties such as:

Metal, spring loaded bypass valve
high density, good flowing filter element
Strong support for filter element (better filters have support that goes for the lenght of the filter. Some only support the top and bottom causing the filter to collapse with age)
Solid gasket desgin as part of the filter not just glued on top
Well machined thread bore that decreses cross threading.
Rolled (as oppsed to pressed) lip on the end of the filter.

Also for all 95+ monte carlos (with the excpetion of the DOHC and the 3.9 60v6) go for the filter for the 4.3 v6 found in Blazers and many other v6 GM truck engines. The size and thread are excatly the same. The filter is longer helping with heat dissapation and providing a larger filter element.

On 2nd gen w-bodies (particuallry the 3.8 equiped cars 00-05 SS's) the clearnce for the larger filter is close but it will fit.