Moderators: Please, please do not move this thread. This is the most active Forum you've got, most active among the Car-specific Forums anyway.




I know this gets discussed many times, and maybe if this thread gets some decent action, it should be sticky'ed. Anyway...here goes my thoughts, based on a conversation with a friend, who I dearly trust as a mechanic and many things read about synthetic oil.


My friend who is currently a BMW mechanic (and I think he also works on Toyotas at the same-owned dealership), told me this when I questioned him on the value of synthetic-

He said that in every engine they've torn down that has a verifiable history of running only synthetic (mostly BMW's serviced there), the internal components are very clean, like new, compared to an engine that has only had conventional oil. He said there is no varnish build up, no sludge, no nothing. He said even the best maintained engines ( I'm taking that as someone who probably goes 3,000 to 4,000 miles between oil changes), there will be a small amount of varnish and at times, some sludge. He did say you would have to look for it.

Him? He said it it usually 6-7,000 miles before he changes his oil. He drives an old 1990-something Camry Station wagon to work and runs full synthetic in it.




I have never used synthetic. I have used Pennzoil, Havoline and currently use Valvoline. I will say that the best results for the oil staying the cleanest is when I was using Pennzoil 10W30 in my 1990 Mazda B2600i truck. I was also changing it at 2,000 miles. It would almost look like fresh oil.

So....what brings up this thread is my pondering whether to switch to full synthetic on my vehicles, which I currently have three, and probably will have three until our 8 year old reaches 16 or 17.

One car is a new 2005 Accord 4 cyl. It has 2400 miles on it and yes, I dropped the new oil too early, but I'm not worried about it. It's on it's 2nd oil change. I will probably drop the current oil in it at 4,500 miles or so. Looking at going synthetic then, but Valvoline 5w20 Syn is tough to find. About the only Syn I've seen around here is Mobil 1 5w20, which I'm not afraid of, just wanted to stay with Valvoline. Heck, I may even go back to Pennzoil.


Next car is my daily driver, 1995 Accord 4 Cyl. 135k miles on it. I bought it about a month ago, engine was nasty inside. Nasty as in I changed the oil in it the minute I got home with it and within 25 miles on it, it was very visibly dirty. I changed it 500 miles later and have about 1200 miles on this fresh oil and it is much, much cleaner. I'm thinking a couple more oil changes before even thinking about going synthetic on this one.

Other vehicle is a 2000 Chevrolet Silverado with the 5.3L engine, 94,000 miles on it. It's always had Valvoline 5W30 in it, changed regularly, although it has probably seen some 5,000 mile oil change intervals (maybe 2 or 3.)

I'd like to sell the truck and buy a smaller, 1990's model truck to have as a yard work truck. But I may also just keep the Chevy. It needs some repairs, but runs like new, has been a good truck, and rides like a dream.




So....

Let's talk about the VALUE of synthetic. If you change your oil at less than 3k mile intervals, don't run around like a mis-guided 20 year old, and maybe drop an additive in the oil every now and then, is synthetic really a good move? Even if you stretch the intervals to 5,000+ miles on it?

Longest I've kept a vehicle is 100k miles, but I'd like that to change. I'd like to start keeping them until...



What say ye?