Proven habit? In an era when extended oil change intervals (using high quality oil) have engines lasting a half of a million miles, what do short intervals (as in shorter than factory recommended) prove? Nothing.

 

The great debate continues....just want everyone to know this is a highly debated topic and at the end of the day there are only two things we'll agree on.

1. Check the oil level on a regular basis
2. Change the oil and filter......the debate is when to change it.

 

X2.

Exactly.

 

Full synthetic is better for a lot of reasons. It lasts longer, cleans your engine better, and has more protection. The only good reason to use conventional anymore is for old school cars.

Remember that not all oil is the same either. It is worth it to spend the little bit of extra money on the more expensive stuff. Same goes for oil filters.

Also, if you live in an area that gets below 32 degrees, use 5W-20 instead of 0W-20. The first number refers to temperature rating. The 'W' stands for winter, not weight. So 5W wont turn into sludge in low temperatures.

As far as change intervals go, I wouldn't ever wait longer than 5k miles. Some new oils say they can last up to 15k, but my car is worth more to me then the 20$ it takes for an oil change every 5k miles. I wouldn't go past that. Change your oil filter every oil change too. Its 5$. Why risk it?

 

I have an 03V6 (no maintenance minder). The owner's manual gives 3,750 miles for severe interval, and 7,500 for normal conditions. I don't do all stop and go, but most of our driving is short trips (less than 5 miles). I've been changing the oil and filter at 5,000 miles. Should I go longer? People keep saying "you can go longer intervals with synthetic oil" but that's not what the owner's manual says. I use synthetic, because I think it's better, I don't use it because I want to change it less often.

 

I wouldn't go any longer than 5,000 miles but thats just me. Synthetic does last longer because of the additives in it. Owners manuals dont take into consideration the quality of oil you are using.

If you use penzoil then you need to change it every day until you change your brand of oil choice.

Mobil 1 and Valvoline are the way to go.

 

The owner's manual does say this: "When using synthetic oil, you must follow the oil and filter change intervals given in the maintenance schedule". In other words, using synthetic doesn't change anything.

 

Ummm, no, you have it backwards; 0W-20 oil will outperform 5W-20 in all temperature ranges, and the colder the temperature gets, the more 0W-20 will outperform 5W-20.

A few comments:

1. I'm thinking you have somehow arrived at the 5,000 mile OCI using some old school metrics. The thing is, Used Oil Analysis proves quite conclusively modern synthetic oil run in a relatively modern engine will be good for at least 10,000 miles.
2. Changing the filter every oil change is also of dubious benefit. Believe it or not, a used filter with 10,000 miles on it will keep the oil much cleaner than a brand new filter.
3. Funny thing, if you look in the Owner's Manual to my 2001 Honda Accord EX, you will see that Honda recommends an oil filter change every 15,000 miles.

 

Using synthetic changes a lot of things actually.

Also, I didn't say anything about synthetic or conventional having to do with OCI. I said quality of oil has everything to do with it. Once again, if you use crappy cheap oil, the additives in it are going to wear out a lot faster than better quality oil. Thats why the general rule of thumb is about 5,000 miles. I change my own oil every 3,000 miles, but I recommend to anyone else every 5,000 because:

1: I dont know what brand of oil they are using
2: I wouldn't recommend to change their oil at 15,000 miles if they are using oil with parafin wax in it (Penzoil) or other cheap oils

 

Have you never seen what an oil filter actually is? Its a paper filter. So to say that the more clogged up that paper filter gets, the better it will filter oil isnt correct. If that were true, why not just never change your filter and it will filter out the oil better and better with more miles?

Eventually that filter will get so clogged that it will run through the bypass and not be filtering at all.

The bottom line is, I am going by what ASE recommends. The difference between 0W-20 and 5W-20 is next to none. 10W-20 does give you about a 1% increase in gas mileage though!