When do I change the oil?

Hi. What type of oil are you using. What dose the package say. Follow it!

To the OP, change it at 5K miles if using dino oil. Just my opinion.

Regarding the soap comment, I raced a 1987 Dodge Shelby CSX for 6 years using soap, specifically Mobil 1 15W50 racing oil. That was some great soap. I never had an engine failure (car ran perfectly when I totaled it).

Change the oil every two years or so and have fun.

New 2015 Toyota Highlander owners manual (and fill cap) specifys 0W-20 full synthetic oil for 3.5 liter V6, with suggested 10,000 mile oil change intervals. This was new to me.

My 6.2L F350 gets Mobil 1 0W-30 every 7500 miles. That's when the monitor starts telling me to change.

I'm through with all that every 3K, 4K, 5K stuff.

gmcsmoke wrote:
if you want to know for sure get an oil analysis; other than that it's all conjecture.

That's very true, but for $35 it's just as easy to get a good filter and fill 'er up with some soap.

if you want to know for sure get an oil analysis; other than that it's all conjecture.

davehultin wrote:
I'm coming up on the first oil change on the new (to me) 2009 Suburban. What do I believe ... the odometer which has 5000 miles since the last oil change, or the computer that says there's still 43% oil life yet?

Thanks,
Dave

By some estimates, the GM OLM is conservative by up to 50%.
Not suggesting you double the service interval but you are quite safe in using the OLM to judge the oil changes.
GM designed, developed and warranted your engine - they would not provide oil change recommendations that would jeopardize it.
Back when the OLM was developed, the oil companies were up in arms as they sensed a loss of business - hence the continued recommendation of 3000 mile changes (which my GM dealer has only just discontinued!).
GM's response back then was pretty much along the lines of my second paragraph. Following the OLM recommendation could not void your warranty.
Now that GM is including the first 4 service visits in the price of a new vehicle (I drive a GMC Acadia everyday) the dealer that was pushing 3000 mile changes will not carry out the "free" service unless the OLM shows less than 10% remaining. FWIW I get about 7500 miles before I'm down to less than that 10% remaining.

I use Mobil1 and I run my oil to 4000 miles then change the oil filter and top off the oil and run another 4000 then change.

According to my edge insite at the first oil service I am about 60 percent and by the time the second change comes up I am at about 20 percent give or take.

This was always done with a/c delco oil filters. I just changed to wix oil filters on this last change and seems to be holding up a lot better. Not sure but maybe the wix does filter better. I am going to run them for a bit and see.

The 3000 mile oil change was important in the 70's, when engines were far less efficient, and oils were closer to crude. Modern engines are designed with closer tolerances, and far less blow by, so the oils are absorbing less crud as the engine runs. The oils are also made far better then 30 years ago. The people that designed the engines know far more about their engines then most people typing on the internet, so in almost all cases you are better off going with their recommendations. For most of us all you are doing by 3k oil changes is spending more money then you need to, and causing more waste oil and filters to be processed then actually needed. If you want to get some stupid long oil life, get secondary oil filtration, run a good synthetic oil, and get analysis every 3k until you know how long it lasts, then go to 50%, 75% and 90% on the analysis. Some people are getting upwards of 50k on the oil, only changing the filters and adding make up oil (for what is consumed in the engine and lost in the filter changes).