Synthetic Oil

[cruiser69]

I have an 02 GT 3.8 with 100k on the engine right now. Would I see any benefit to changing to synthetic oil? This is my daily driver to work and anywhere else we go to keep the miles off my wife's car for now. I change the oil and filter every 3k miles and would probably change the synthetic every 5k miles. I think I would have a hard time going longer than that without an oil change. Thanks for you opinions.

[GTP Dad]

There is no bad time to change to synthetic oil. At the present time with your 3K oil changes your engine should be clean so synthetic will work well. If you intend to change it at 5K miles though it may not be worth the extra expense as synthetic will run for 7.5K easily with no issues. Just make sure to use a quality filter like a Wix or other name brand. Stay away from Fram (aka Orange can of death). One drawback is that you may see some leaking around the valve cover gaskets as the stock gaskets may leak with synthetic oil. Check ZZP for a good set of synthethic gaskets and change them if the stock one start to leak.

[JonJon68]

I changed over with high mileage full synthetic Mobile One at 100,000 miles. No problems, no leaks and engine seems happier....Of course, like GTP Dad I'm also using the Wix filter.

[cruiser69]

Are the Wix filters good for the entire 7,500 miles or do those need changed in between oil changes?

[GTP Dad]

Yes, Wix is one of the best filters on the market. Amsoil recommends them for use with their oil that has extended oil changes up to 12,500 miles.

[rickisrad]

I use full synthetic with the k&n oil filter and a bottle of synthetic lucas additive. I change mine every 5k but I could easily go 7+ with it. I push mine a bit performance wise so I change mine a little more often than I should. I figure every 4 or 5 months I can afford the extra protection and piece of mind.

In your case I would use a good high mileage semi synthetic oil and you could get 5k out of that with a good oil filter. once in a while I will put seafoam in the oil a week before I change the oil to clean out gunk and keep the lifters moving smoothly

[Stealthee]

You are not going to see any benefit by changing to synthetic now. If you are religious with your oil changes it is not going to be that dirty at 5,000 miles so all you will end up doing is spending more money on oil.

[JonJon68]

cruiser69 Also had a question on whether to change the oil filter at about 3,000. I always go 7500 between changes however I also change my filter about half way through. Is this a good idea?

[Stealthee]

No. Actually the more the filter is used the more it filters. It used to be recommended to do an oil change every 3000 miles, but only change the filter every 6000 miles.

[FISH96]

It used to be recommended to do an oil change every 3000 miles, but only change the filter every 6000 miles.

formally recommended by whom? oil companies, filter companies, engine manuufactures?
this procedure would place the volume of contaminated oil in the fresh oil added to the oil pan. could be as high as 20% to 25% contaminated oil contained in the filter left on the engine


Fram (aka Orange can of death)
Why is fram named the orange can of death?

[Stealthee]

You obviously have a misunderstanding of how filters work.

How is it going to place contaminated oil into fresh oil?

Look at an owners manual. Car manufactures recommend it because as it filters the contaminates are caught in the filter. The more contaimates caught, the better the filter works.

And Fram is called the orange can of death because it is orange and its a crap filter.

[FISH96]

I am now ediified.