C1Forged

Yes, and no. The pollutants that get into the oil is gas during blow by, and when gas mixes with oil it breaks it down. Synthetic oils have additives to soak up the gas and slow the break down, but if pollutants get into the oil it will break down due to the chemical reactions that take place. The only pollutants oil can pick up without breaking down are metal shavings, and at that point you have bigger issues than what oil interval you're draining at.

Mr. D

I'm referring to people that run synthetics 30K miles! I'm no chemical engineer, but I couldn't sleep at night with oil that old in my Mustang! In My GT below I go 6K miles with Mobil 1 because of the way I drive it, & with the new Edge I may go 10K! We have a Toyota with over 300K that runs great using Walmart Tech 2000 full synthetic.

Coosawjack

Mobil I and Motorcraft filters every 5,000 miles (EASY to remember) and currently have 266,000 miles on my Supercharged 2004 Mercury Marauder with ZERO oil usage between changes!!

FORD engineers their vehicles for a 300K mile life span with reasonable care!!

User 92421

For the love of Ned, your oil can far outlast the filter, very few filters can run more that 5k before they go into bypass many will be in bypass much over 3k. As least change by 7 k or you can do like I do, change the filter and add a quart full synthetic at 5 k then a full LOF at 10 k

C1Forged

I've seen a number of guys who have been brave enough to run a high mileage drain interval. On one occasion it was a 50,000 mile change interval before the oil no longer tested as "recommended for another 5,000 mile use". Granted other factors have a lot to contribute in that oil change. Filters were changed every 7,500-10,000 miles, oil was tested every 5,000, and I believe it had a secondary external bypass filter. Topped off for the amount used in the test every 5k, I believe the result was 1 extra quart being added during the entire 50,000 mile test.

It really comes down to careful monitoring. A lot of people don't feel comfortable running more than 5,000 miles on an oil change, but then again, a lot of people don't feel comfortable standing on a reinforced glass balcony over the Grand Canyon. With the proper testing and monitoring, you would be surprised what could be accomplished.