If I resided in Alaska or Cali deserts I would be using synthetics for sure.
I'm still thinking about it once my ride gets over 5K miles on it.

You can get Syn cheaply these days (21.00 for 5 quart jug). There is no excuse not to use it.

I totally agree.

I use real oil. So far, put about 65k miles on the runner and 120k on the civic. Both look great under the valve covers. Cam lobes still look nice and shiny. No sludge in oil pan either. Used to run syn in my other cars, but was told by an experience engine rebuilder that changing more often is better than running syn with a longer change interval.

This brings up a good point ......... My old man would run the cheepest oil and filters you could get and never had any problems with sludge or excessive wear. He would always change it every 3 months or 3k on the dot and live by it.

He would always get 200 to 300K out of all his cars or trucks without a hitch.

I think we all worry about the best oil or the best filter to much just drive the darn thing and change it often it will last a long long time.

I agree with the last two posts changing oil often is the key. You read about people going 15,000 to 20,000 on one oil change. Right now I use 3,000 for dyno oil and 5,000 for synthetic. My old Honda has 222,000 miles and still gets good mileage.

I feel a lot of the problems with people getting into trouble is going too long in the changing of oil. To me changing often is more important than the type of oil or filter you use.

I also consider how much time the oil has been in the engine.

I use M1 syn/Puralator PureOne filter and I go about 8000 miles or 9-10 months whatever comes first and my Runner now is a shade under 140k and just had a t-belt/water pump,compression check and a few other maintenance items and fully inspected by Toyota and it's in perfect health for it's age;the only thing that doesn't work is the power antenna which went at 130k.

I drive my 4Runner hard and it sees intermediate trails about 10 times a year and it's been surprisingly trouble free......knock on wood.

Contamination is one thing, breakdown of polymers and lubrication properties is another.

The oil filter should get rid of any solid contaminates

Its believed that synthetic oil will "break down" less at a molecular level.

I have a V6/2000/4X4/LE and have about 172000 miles, I've been putting M1 Syn Oil since 90K miles on it. I changed oil/oil filter regularly between 7500-8000 miles. Never have problem with pinging, except my gas mileage been about 16/19mpg city/highway. Not sure if this is the norm gas consumption. Muffler and cat converter still original.

You sir are 100% correct. How can synthetic not get contaminated the same as conventional oil? It can't! It will be just as contaminated as the regular oil and will need to be changed like regular oil needs to be changed.

PERIOD!

I could say something directly but not being an engineer I'll keep my trap shut or this becomes a cyclical shouting match of "who's right"

Here's three articles to check, the first two short and too the point, the third a longer more indepth look at synthetic vs dino oils.

MANY of the myths about synthetics, some which USED to be true many many years ago have been once again brought up in this thread - but are not understood, take a few minutes to read these or search for yourself and find the truth. Toyota now sells full synthetic (a large sales sign in my local stealership service dept last week) for your runners - if Toyota NOW says it's good does that make it so? Of course not BUT then if they say NO, that then is also not true..

Both have their place, and it's owners that decide what they prefer.

Three "random" articles I picked of a quick search

Synthetic Oil VS Regular Oil

Synthetic Oil Vs. Natural Oil | eHow.com

Synthetic Versus Conventional Oil- Car Craft Magazine

Okay you can flame the skin off me now my .02