Davesmit

Just curious what engine oil folks use in their 17+ year old Accords and the oil change interval.

For instance, I drive a 91 Accord LX w/ MT and I use conventional (cheapest) 10W-40 engine oil I can find that meets spec and I do so all year round (I live central/south US) and I change it every 3k miles or 6 months, whichever comes first.

davexnet

According to the driver handbook, my 2000 Accord SE prefers 5W-30, although it does say
10W-30 is an acceptable second choice if the temps in your area do not go below 20F

Perhaps you should check your handbook

Davesmit

My 91 handbook spells out 10w-40 as an option for warm/hot climates.

I've noticed that when the temperatures are at least 70F my car is supple with both the engine and the stick shifting. IMHO, 10W-40 definitely works best in the mid spring to mid autum time frame here in AR. I used to do it briefly way back in the days, to change the oil twice a year always in April and theb again in October, such that 10W-40 was used in the warm/hot time frame and "5W-30 energy conserving" during the cold time frame. I'm now incresingly convinced to go back to that schedule.

Dave

Aradin

10w30 Supertech with a basic Fram on the daily. It's got high miles and cold piston slap so it needs a little extra viscosity on startup. Winter time I might add half a quart of Lucas oil stabilizer to shut it up a bit more. I change it twice a year.

5w30 Castrol conventional in the turbo car. Usually run a Bosch filter. Change it twice a year also even though it barely gets any miles put on it.

Davesmit

Aradin, what do you think about the "adage" that high mileage engines could benefit from higher viscosity oil compared to when the engine was newer? Thus, transitioning from say 5W-30 when the engine is newer to 10W-40 after let's say 140k miles. I ask this because I noticed that you don't go higher than 30 grade on the hot viscosity numbering convention even though your daily driver has very high miles. I would've thought that higher viscosity on the second number set would be better since a "worn engine" as in high mileage would have higher clearances in the internal components from all that driving wear so higher viscosity would lubricate best?

Someone told me one time (or should I say that's what I understood) that low viscosity is what you want since then more oil can flow when the engine clearances go up with high mileage. But I've also heard the opposite of this which is that higher clearances due to engine wearing calls for higher viscosities.

Dave

Aradin

Honda allows for a lot of different weights from the factory. If you take a look at the FSM they have pretty much every oil weight you can use and the acceptable temperature ranges for use. As long as you're not running a 20w50 in below freezing weather or something, it should be fine with whatever your preference is.

Honda builds good engines for the most part. The F22 series is a tank of an engine and they last forever with basic maintenance. I don't really see where it's necessary to change oil viscosity due to an arbitrary mileage number. Once the engine is broken in (within the first the first few thousand miles) there will be very little, if any, bearing wear assuming the engine is cared for properly. Ring wear is a bit of a different story but generally these don't start losing ring seal until beyond the 300k mark.

Personally I just like to run the thinnest oil the engine was designed for, most of the time. Running a thicker viscosity "just because" is just going to hurt your fuel economy and performance. MotorTrend/Engine Masters did a video about this with a dyno and test engine. Short version: unnecessarily thick oil seriously robs power and so does an overfilled sump. There's a reason why most all newer vehicles are running 0w-20 or thinner. In the case of my daily the oil pressure is fine and the piston slap is just caused by skirt/bore wear. Common with high mileage in these cars. Once the engine is up to temperature the piston/sleeve expand enough to take up the clearance and stop rattling so a heavier warm viscosity isn't necessary for me. I put a little bit of Lucas in during the winter in hopes that it will stick to the cylinder walls a bit and help cushion the slap on cold starts.

Davesmit

Good stuff Aradin. Thanks for the insight!

It's interesting that thicker oil robs performance from the engine but it does so without harming the engine. This begs the question, if using the vehicle for normal driving (to and from work) is there any advantage to thicker oil? Better lubrication, but probably not even that.

Dave