I have a 2004 Honda CRV, auto, AWD, LX with 138,000 miles. I talked to my shop about getting it serviced and what oil should I use. I was thinking Synthetic but he recommended sticking with conventional oil. It calls for 5-20 and he said maybe I should consider changing to 10-30 weight. What do you think?
Stick to the manufacturer’s recommendation.
why do you need to change oil viscosity?
It was a conversation at the repair shop I take my car to and he suggested the change from 5-20 to 10-30 engine oil. And before I do I wanted a second opinion. He said it was better for an older engine. I'm not so sure.
if it's not leaking or burning oil then I see no reason to change. I also don't understand the need to use conventional oil when synthetic is superior in every way (except cost).
My first thought was synthetic until he said that. I have no leaks or oil use. I just want to do what's best for a very good running 138,000-mile engine.
It all depends on where you live and the winters you have there for the "winter" weight (xxw-xx). You want the oil to flow very easily and quickly during really cold winters, meaning you want a lighter weight for the winter part. As for the normal operating temperature weight, you can switch to 30 and it won't damage anything. If it's really hot where you live, you want a slightly heavier oil like a 30 weight instead of 20 to prevent the oil from "thinning" out quickly due to the heat.
I live in Southern California and run 5w-30 in my BMW 428i, even though they recommend 0w-20. Nothing is noticeable whatsoever between the two, it's just my preference for where I live.
I would stick with the manufacturers recommendations in the owners manual based on ambient temperature. Older vehicles like yours were not really designed to take advantage of synthetic oils. There are lots of opinions about this, but I have seen too many people put synthetic in older engines and severely regret it when their seals start leaking that expensive, synthetic oil.
ostensibly, this was an issue with the first synthetic oils that came on the market. Something that has since been rectified.