My 2002 Accord has 79k miles on it. I bought it used w/ 38k miles on it, and have changed the oil and filter every 5k (or so) miles using conventional oil w/ no problems. I was wondering if I would benefit from changing to a "high mileage" conventional oil or a synthetic, or just sticking with what has worked fine so far. Is a "high mileage" conventional oil just a sales gimmick? Seasonal temps here range from the 20s to 90s.
Thanks for the input!

 

i wouldnt say 79k is high milage, i put synth in mine at 52k and i love it, it feels like your car runs better, im stickin with synth till it bleeds.

 

I don't think 79K is high miles, either....It just seems like most high mileage oils are aimed at vehicles with 75k and up.

 

synthetic would prolly be ok for the amount of miles on your car but i have a 97 accord with 177k miles i used conventional for ever then decided to try synthetic....worst mistake i ever did now it leaks through the rear main seal alot.i'd stick with what works if you want extra protection try adding lukas to your oil.lukas will give you more benifits than any oil except maybe AIMS oil.

 

Synthetic only leaks because the molecules are uniform size, unlike conventional, and much smaller.

 

Synthetic is some serious stuff and worth ever penny if you plan on owning your car for the long haul. Changing regular oil every 5k is not a good idea, that's how often I change my synthetic. Engines with high mileage that have been running synthetic from the start won't leak or burn oil. Look up the study they did with NYC taxis and synthetic oil. If I remember correctly after 200k or 150k miles and changing every the oil every 5k the engines show little to no wear. I don't remember the exact numbers, but it was a lot of miles, and virtually no wear. Hell I even run full synthetic 2 stroke oil in both my boats, full scale and R/C.

 

My car started leaking oil after going from conventional oil to castrol synthetic blend. Had some gaskets replaced for about $50 and the leak stopped. It's up to you but there is a chance your car will start leaking once you switch to synthetic. I've been told by many mechanics that the two aren't too different and that the best thing is to change the oil on time. I would say 5k miles is kind of pushing it if you spend most of your time in traffic. Personally, i would just stick to conventional oil and change it every 3k miles or 6 months. Clean oil also keeps the seals and gaskets happy.

 

An engine with small leaks will leak more oil with synthetic, however on a sound engine, synthetic is better.

In an earlier post, "AIMS oil" was mentioned as a good additive. Amsoil is IMO the best synthetic with Royal Purple in a close second to tieing status .... I still have some concern about moly.

In that same post, Lucas additive was mentioned. This is excellent stuff. I use their stuff for fuel and tranny treatments and I've used the oil treatment, but for oil I prefer Marvel Mystery Oil.


EDIT: Regarding the post above this, conventional oil should be fine for 5000 miles and synthetic for at least 7500 miles. The best method is oil testing to be sure, but I've personally run Amsoil Series 2000 0W-30 for a full year interval, two years consecutively, with a filter change and top off at the half year mark and it was fine. That particular oil is good for 35k or a year. This was done on an '89 Z24 Cavalier and the car was sold with no engine problems whatsoever.

 

Thanks for the opinions, folks. I think I am going to stick with the dino oil that has gotten me this far. My next (new) Honda will get the synthetic treatment for sure. Are the alleged additives in a high mileage dino oil worth it, in your opinion?

 

I've owned cars for lots of miles. Had my 89 Saab for 220k miles & never used that high-mileage oil. I think I would only consider it if the car started having high-mile problems like leaking seals or loose rings.