Synthetic oil

[Flashmn]

If a mechanic said that I'd go to someone else.

[darcsyde]

i've used royal purple as well

[htoler]

he didn't say it would hurt the engine just that there is no way it could protect the engine for 25 thousand miles between oil changes he said it was because of the heating and cooling of the engine and the production of moisture from that. for the reason it would not last that long.. he said 7`500 miles would be really pushing it..if a synthetic was used..

[tnmk]

His opinion. not based on any facts what-so-ever. Go to bobistheoilguy.com and read some of the results of used oil analisys. There are many that are over 10k and the oil is still fine. Though you won't find many over the 15k mark, they are there.

In other cases where people use premium air filters and by-pass oil filter systems there are people that go over 100k doing periodoc UOA's.

[Flashmn]

I change the oils every 10,000km on the benz. Service states 15000km.. I think its too much, why risk it.

Ok so did drive 38000km on some shit oils in my nissan. They stank to high heaven when I took them out. No other damage was present... Still, I dont think its that good.

[htoler]

tnmk how many miled do you go between oil changes??

[wantin150]

Originally Posted by Flashmn

If a mechanic said that I'd go to someone else.

+1 here. Bad, bad, advice from the "mechanic". There are some situations where synthetics can cause issues (leaks). These are usually on older engines with a sludge problem. The synthetics will "clean" the engine a little and a leak could develop in an area previously blocked by sludge. This is not an oil issue, per se, but an issue that previously existed and was brought to attention by the synthetic oil. Some brands of synthetcis seemto be "consumed" more by some engines.

The bottom line is: Run what you want to. Change every 5-7.5k. If you want to extend OCI's, get UOA's done until you find the max life of that oil for that engine.

[Flashmn]

There are some situations where synthetics can cause issues (leaks)

Yeah and even then its a matter of old gaskets, etc. Also older engines burn synthetic oil more, because the oil finds its way past leaky seals to the combustion chamber...

Didnt happen to me and I have a 1990's corolla.

[tnmk]

When I used Mobil One once b4 I changed to Amsoil I went about 12,000. Now with the Amsoil I'll go a year which for my family is about 18,000. That's alot of hwy miles.

Cars run great.

Prior to using synthetic I would go 5-6000 on old dino oil. I've never had any oil related probelms.

Many probably think I'm nuts, but I know my cars will still go 200,000 miles easy. I won't keep them longer than that.

Call me new school.

[20XRS06]

Amsoil 5-30...