I know this seems pretty trivial, but I just bought a low mileage, 2004 element and I really like this little car and want to baby it. Honda recommends 5-20 oil and I’ve read discussions on Honda owner discussion boards that 5-20 is preferred because of the tight tolerances of Honda motors. I think the original owner used synthetic oil, to boot. My mechanic, who has always given me great service, said once you use synthetic oil you’re committed to it because if you switch back to regular oil the seals may start leaking. He thinks it’s a waste of money. He also used 5-30 on the oil change. So, 2 questions: Anybody else heard of leaking seals after using synthetic oil? and Does it matter if I use 5-30 instead of 5-20?
You can switch back and forth between synthetic and regular oil anytime. The urban legend on synthetic oils was if it was used in an engine that had a lot of miles and was run on regular oil the seals could leak.
As far as using a 5W30 oil instead of a 5W20 oil, that’s okay too. Honda recommends a 5W20 oil because it saves fuel. That’s because it takes less energy to pump a 20 weight oil through the engine than a 30 weight oil once the engine is up to operating temperature.
Tester
As tester wrote, your mechanic is well behind the times when switching could cause seals to leak. It is also right about the weight. Unless you have some reason to use the 5W30 I would stick with the 5X20. It will save a little fuel, and it will protect your engine just fine.
Joseph is right; however, we do not know where you live and drive. If you fill the car with cheap 5W20 non-synthetic oil and drive across Death Valley in July fully loaded, you will cause considerable engine wear. This is of course an extreme case.
If this was my car I would use 0W30 full synthetic (such as Mobil 1) which is good all year round in any part of the US, including Alaska. This will give you both good mileage and maximum engine life!
As others pointed out, the CAFE mileage standards are largely driving the oil recommendations. Honda sell a lot of trucks and SUVs and has to start worrying about fleet average fuel economy. My Toyota is a 2007 and the recommended oil is 5W30.
Agree your mechanic needs a refresher coures inn modern engine lubricants.