I have a 1996 Honda accord EX with a 2.2L engine. I’ve always been using conventional motor oil for my car, but I heard that synthetic oil is a lot better oil than conventional. Now I’m wondering if I would be able to use synthetic to get the engine running cleaner and less frequent oil changes?
I asked this because I have heard that using synthetic oil in old engines may cause oil leaks, but I really don’t know if this is true or not?

 

Sure you "can," but it might cause problems. I only tried full synthetic once (some sort of Pennzoil super duper something or another) at about 200k, and it ran out of every opening it could find in my crankcase. I should never have tried it, but a friend swore by it.

I use Castrol GTX High Mileage 20w50 Synthetic Blend (in the green jugs) and get good results. Except for that one time, I have always put 20w50 Castrol GTX in this Honda.

 

But, if you think that I may have problems with it, it may not be a good thing. My engine has over 200K and I have been always using conventional motor oil. I use Castrol GTX 10W 40. I originally used 5W 30 as the engine requires, but I put in a thicker oil because of the higher mileage. I was considering using full synthetic Mobile1 5W 30, but I wasn’t sure if this was going to improve the performance of the engine or would it make it worse and have issues with it as I may have leaks that I have heard about.

 

stop the spread of misinformation- read all of this. understand it.

use the right oil (5w20 for your F23Ax) unless you have good evidence that something else is better suited. Causation vs. correlation: synthetic doesn't "cause" leaks but it may be correlated with an increase in leakage in certain situations.

 

Synthetic won't cause oil leaks on any modern engine.
What it may do is find leaks, but that's something that needs to be fixed anyway.
Higher mileage does not equal thicker oil.
Now what your climate may be would be more indicative of the oil you should use.
It gets hot here in Calif during the summer, so I switch to 0W40 for better high heat/load protection. But when it starts getting cooler, I switch back to 5W30 for those cold mornings.
I'm a Mobil1 fanboi so I just use that stuff and the filters.

Synthetic oils are made from a better more stable base stock. This allows the oil to be more durable and sheer resistant than regular dino oil, everything else the same synthetic will last longer and add better protection.

Only real way to tell if the oil you are using is fine for your application is to have a sample sent off to an oil analysis lab and see what the results are.