Hey guys. About to get an oil change soon and I have 5qts of Mobil 1 full synthetic 5w-20 but I was wondering if there's other oil that is best for my car with high miles. It's currently running 154k miles. I'll be using an OEM Honda Toyo Roki oil filter as well.

 

For an Accord, that is not really "high mileage" but I would run some regular oil in there unless you changed all your seals. Synthetic is more slippery and might leak if you have worn seals. Get some high mileage valvoline maybe in 10w30 viscosity. Its not winter time so you don't really need that thin of a oil in there.

 

Run what the OEM recommends. Which i think is 5w20. If you want to run full synthetic, I wouldnt have a problem with it. Some guys say it makes older seals leak...but Ive never seen it.

The only difference between mineral and synthetic, is the size of the oil molecules. Mineral oil...has differing size molecules(Which occurs naturally) synthetic...is chemically changed...and all the molecules are the same size. The theory is, that this allows the oil to last longer...not break down as quick. But it costs more. Me personally...if the engine has a pile of miles on it...I wouldnt spend the extra money on synthetic. Just make sure you change the oil regularly.

 

^x2 on the regular oil changes!

As far as regular vs synth goes I would run whatever you want to pay for. As far as oil weight, use what the manufacturer recommends, 150k is not high millage for these engines. If the engine is still running strong run what Honda recommends for weight/time of year and driving conditions. I switched to full synthetic @ 150k and didn't have any issues.

Now, if it is burning up oil or leaking, my suggestion is to fix the part that is leaking. There is no snake oil to fix an oil leak or prolong the life of an engine! If you do regular oil changes you shouldn't have to worry about that.

 

run 10w30 conventional for that J30A1 with those miles on it

 

The OP does not have the V6 Accord. He has the I4 F23 model.

There really is no difference between a 10w30 and a 5w30 in the summer time.... They both have an operating temperature viscosity rating of 30. The higher number before the w (winter) doesn't mean it's thicker and stops leaks. If you want to run a thicker oil to try and boost oil pressure due to worn bearings you want to go by the second number..... you would want a 10w40..... I do not recommend anyone run a thicker oil in an engine with tight bearing clearances like our Honda engines. Unless you have proof that your oil pressure is low and running a heavier oil will bring it back up!

 

445,000 miles and I'm still using conventional oil....5w-30.
Go figure.

 

Wow thats amazing. How did you manage to keep the engine running that long?

 

it's easy to get a lot of misinformation when asking a question like this. to make sure you have all of your facts straight on oil specs and properties check out Bobistheoilguy dot com. to take it to the next level, have a qualified and verified lubricant lab like Blackstone Labs do a used oil analysis for you for about $25. they'll also be able to recommend the best oil change interval for the oil you chose to run based on how much it has broken down. you may find that you're changing it too often which wastes money.

good luck.

 

Preventive maintenance.