About to change my oil and wondered what would you all recommend for a '92 Honda Civic VX? What will be best for my engine long-term, and what will allow the engine to work the least, still protect it, and maximize my fuel efficiency? Synthetic? Standard? Any advice is greatly appreciated.
I'd say use whatever has been used in the car for the past 20 years. 20 years is a bit too old to try and switch now. If you go to synthetic this late in the game, the oil can loosen up a bunch of gunk in the engine all at once and cause problems.
I've used regular and synthetic in many different cars. And used to keep fuel records for years. One thing that stood out was that synthetic oil gave better gas mileage. Don't recall the numbers but it showed up on average.
There is no difference between regular and synthetic really. Synthetic has more stable formulation because of more even length hydrocarbon chains, therefore it is able to hold additives in suspension longer and will be more stable through heat cycles and extreme temperatures. Outside of that, there is ABSOLUTELY NO difference between synthetic and regular. You can change between the two of them any time you want. If you were to use a high quality conventional oil, it would have the same effect as a good quality synthetic on your engine, aside from the fact that the synthetic will perform more consistently throughout the range of operating temperatures.
Visit bobistheoilguy.com for more oil information and discussions. They myth that you cannot switch between synthetic and conventional is just that, a myth. I always switch my cars to full synthetic oil when I get them because synthetic has a longer service life, and therefore will cost me less time in maintenance. I have NEVER experienced a problem with switching a vehicle over to synthetic, and most of the vehicles I buy are pre-OBDII vehicles.
Heck, I put full synthetic in a 52 pontiac chieftan the other day that hadn't had its engine rebuilt since some time in the early 80s. Works just fine. Your engine can't tell the difference, and without an electron microscope, neither can you.
I use mobil 1 5w30 in winter. I used 0w20 this summer but will go with 0w30 if I can find it this summer.
I use it because it is available locally at advance (unlike amsoil or honda genuine). It's a middle of the road product, perhaps not as good as ams but at least as good as stock. It's synthetic, so you get all the benefits that FIND pointed out.
I change it every 10k. That works out to about twice a year for me. That's the real reason I use synthetic. Long change intervals. The oil looks about like conventional oil looks at 4500 miles. Not really dirty even at 10k. The manufacturer says it will go that long, so, why not? I do keep an eye on how it looks periodically when I put some on a clean rag from the dipstick.
With my underbelly paneling, anything to reduce the frequency of removing the panels is worth it to me.
Castrol makes what I feel is a close quality product, in fact, it's often on sale. I'd go with that if the oil and filter deal was cheaper than mobil one's.
I've tried tried 0w-20 in the Prius, and did see an improvement in mileage, but you can't get the mobil 1 in the big jugs. Under the factory warranty, I was sticking to the 5000 mile change interval which left buying individual quarts too pricey. I think 0w-30 mobil 1 can be had at wal-mart in those jugs now. If you are switching between 0w- and 5w-, use the 0 during the winter.
Whoops, that's what I was thinking. 0w 20 in winter, not summer!
Yes, not getting it in the big jug is a problem. Advance would let me buy 5 quarts and their filter for $32 at one point. Castrol's "fully synthetic" product with the bosh filter is more like $27. Of course if I buy the 5 quart set I have to throw 5 jugs in the trash instead of one, which makes me sad.