: Oil change timing



Larry05
08-27-05, 09:59 AM
The readout on the oil change says I have 53% left on 4,700 miles on this oil change. That would indicate 11,000 miles between changes. Do I believe this or go with the 7,500 mile recommendation?

What about the new Mobil 1 oils that have a 15,000 mile oil change interval?

louisn
08-27-05, 10:58 AM
I would follow the monitor but never leave it in for more 10-12 months per the manual. All the objective data proves that synthetic oil and even the new dino oils are so much better that early oil changes are not necessary and a waste. The data shows that synthetics are still good even after 10,000 miles and more.

addison_ii
08-27-05, 11:11 AM
I would follow the monitor but never leave it in for more 10-12 months per the manual. All the objective data proves that synthetic oil and even the new dino oils are so much better that early oil changes are not necessary and a waste. The data shows that synthetics are still good even after 10,000 miles and more.I agree with louisn and here is a link with some more info for you.http://www.gm.com/automotive/vehicle_shopping/suv_facts/300_env_emissions/6_oil_life_system.html

john d
08-27-05, 09:41 PM
I would follow the monitor but never leave it in for more 10-12 months per the manual. All the objective data proves that synthetic oil and even the new dino oils are so much better that early oil changes are not necessary and a waste. The data shows that synthetics are still good even after 10,000 miles and more.

louisn - I called Mobil and asked how and why their Mobile 1 lost its lubricating abilities after 12 months.
Did it go sour like milk?
Did it crystilze like honey?
Did it lose its detergent?
Why change at 12 months?
What if I only drive 7,000 miles a year?
The guy told me Mobil is just going along with the manufactures 12 month recommendation and doesn't want to get cross ways with the manufactures. He said using the oil life monitor was the only thing i needed to obey on
Mobil 1 changes.

djfcars
08-28-05, 12:14 AM
I guess I'm wasting money but its cheap insurance. I change all my cars oils at 3,000 miles. I will say that it takes us about 5 months to put 3,000 miles on our cars so it seems its been a long time when I change oils.

My 2 cents,
djfcars

louisn
08-28-05, 09:33 AM
djfcars, MANY drivers feel the same way you do; but the facts prove otherwise.
Also johnd, I tend to disagree with Mobile on the necessity to change after a year even in low mileage situations. I've never seen any data reflecting the low mileage extended time situation. I did read somewhere that in that situation the engine doesn't get hot enough often enough and condensation occurs creating water in the oil. But i think after 10,000 miles or a year or when the monitor directs is proper course. In my experience the computer is usually right.

Smokin' SRX
08-28-05, 02:30 PM
louisn - I called Mobil and asked how and why their Mobile 1 lost its lubricating abilities after 12 months.
Did it go sour like milk?
Did it crystilze like honey?
Did it lose its detergent?
Why change at 12 months?
What if I only drive 7,000 miles a year?
The guy told me Mobil is just going along with the manufactures 12 month recommendation and doesn't want to get cross ways with the manufactures. He said using the oil life monitor was the only thing i needed to obey on
Mobil 1 changes.

:) Hi! All engines produce small amounts of back pressure into the oil pan, by exhaust gases getting past the rings , on combustion. (when it's real bad, we call it "blow-by" and the PCV valve gets soaked with oil!) Some of the gas/mixure has tiny amounts of gasoline in it! this I've read acts like a corrosive, on bearings and rubber seals! Add to this the natural absorbsion of water (like brake fluid does!) and 1 year is a good time to change even synthetic oil, with only 5-10,000 miles on it. Any longer and the "additives" cause harm.
Made sense to me! Good luck!

miked
08-28-05, 03:17 PM
When BMW first went to extended oil intervals, where you could go up to three years without an oil change, the problem was not the oil lasting this long, but the oil *filter*. They had problems where the filter would disintegrate, and land up in the engine. So now they recommend oil changes every X months (either 12 or 24, can't recall), regardless of what the oil life monitor is telling you.

MortnCyn
08-28-05, 04:31 PM
Depends a lot on driving conditions. If mostly highway miles compared to dusty conditions, short trips etc.10,000 miles plus on synthetic is not a problem. Synthetic lubricants withstand heat much better than mineral based oils. The key words in industrial applications for lubricants used in air compressors and other industrial equipment is "normal operating conditions". That is, not running over recommended temperature ranges and clean air intake conditions. We changed at just under the 12,000 mile mark. I did have them fill a small sample bottle that I labeled with the date and mileage.

DVC-Don
08-28-05, 08:35 PM
I had the wifes first at 3,000 and now follow the monitor. When it gets below 10% I bring it in.

miked
08-28-05, 11:07 PM
It seems that the SRX's monitor (AWD V8 at least) is geared towards a change every 10K miles, which goes up or down based on your driving conditions/ambient temps. Based on how we're going, our first change will probably be around 9K miles . . . .