Fifthwind

I'm meticulous about oil changes and because of this, almost every car I've owned has made it to near 200k miles with no problems. However, I've always been a dead-dinosaur Mobil-1 kinda guy.

My current mustang (05 GT) has 75k miles and everyone keeps telling me that synthetic is definitely the way to go once you get into the higher mile range, (Obviously it would also be good from day one)

Anyway, I hear that you can get away with a little longer interval between oil changes with synthetic. Some say that as high as every 10k is okay... but I'd be too obsessed to try that. How about every 5k miles? That would double what I'm currently doing and would make the added expense a wash.

Who has been using synthetics for a while and has some opinions, and dare I say "facts" about this.

Some info on my usage:

<1> Daily driver, used 7 days a week.
<2> 60 miles a day average commute / 20k miles a year.
<3> 85% highway / 15% city
<4> I play a little hard on acceleration and highway on-ramps, but that's about it.
<5> Winter 40's Summer 105+

mk70ss

I've had my '08 GT since July and put 2000 miles on it since then. I don't know what oil the previous owner was using (the car has 21000 miles total now), but when I put it away for the winter, I did an oil change using Mobil 1 synthetic. I'd appreciate any info on the subject as well.

Nuke

I've been using full synthetics for years on my SUV's and now the Stang. I typically go 10k miles or 1 year; 8k miles if I consider that to be severe duty such as excessive towing on the SUV.

Our Stangs come from the factory with synthetic blend which is good for 7500 miles according to Ford. I'd change that at 7k miles unless I did a lot of city/stop-n-go driving. The g/f's '06 pony gets changed at 5k miles due to her previous city driving but now that we're more rural we're going with 6-7k miles on her blend.

I've had multiple vehicles that have gone well beyond 150,000 miles; a few of which past 200,000; prior to my selling them with no engine related problems. No oil consumption, no burning oil, no performance issues. I've had oil analysis training in the past and had some very lengthy discussions with the instructors. There really is a lot of old school mindsets preventing people from taking advantage of what synthetics have to offer; mainly longer change intervals. 10k miles is very conservative but the only way to know if your engine is healthy (regardless of what oil you use) is to perform oil analysis. Unfortunately, it 's a financial toss up whether to change your oil or do the analysis.

But you need to educate yourself and make a decision that suits YOUR comfort level. But based on your usage info, I'd definitely feel comfy at 10k miles.

Dean Martin

I did my first oil change at about 1K miles, and then switched to synthetic at about 8K. I drive similar to you and have 156K currently and typically change mine at about 12K intervals. Not using any oil between changes.

siggyfreud

In reality, even todays conventional oils are good until past 3k miles. The old "3 month/3000 mile" recommendation hasn't really adapted to how oils have changed. Your conventional should be good for 5k miles, and synthetic will most certainly be.

D'prived

I've been using Mobile 1 for many years now in every car I own. I change oil and filter every 6k miles or 6 months, which ever comes first.

mtyson227

Every 5,000 miles for me using full synthetic. I'm less worried about the oil and more worried about the filter. I drive about 18,000 a year.

Siber Express

I still change my oil and filter around every 4000 Miles using full synthetic Valvoline.
Even if you go to Mobil 1 or Valvoline's web site they do not recommend going over the recommended oil change intervals.
On a side note I switch my 5.4 in my F150 over to Mobil 1 at 65,000 miles and it started using oil, went back to Motorcraft Synthetic blend and it stopped. Talked with a couple of friends that had the same problem and went to Valvoline without any oil consumption.

JAMAMAN

I use the recommended oil grade that is mentioned in the manual. I change it every 3k miles and never had a problem and my cars have always lasted forever. My car is a daily driver in all kinds of weather (rain,hail,sleet,snow, you name it) and I drive the **** out of it all the time with no issues. My main issue is changing the filter, I find oils can last a while but I don't like to play games or cheap out on filters. Oil brands is a subjective matter and choice, because people will swear by their particular brand. Main thing is that if aint broke don't fix it, I mean if your method has worked for you then don't change it.

ffk_pennywise

Mobile 1 every 10k miles for me. Standard Motorcraft filter.
Daily Driver - 70 miles per day/ 5 days per week.
Car has 92k miles on it and runs like new.