synthetic oil

What is the maximum mileage recommended in your operators manual for a standard [not severe] duty cycle? Go with that. Anything more has no safety attached, though some of us like a hint of adventure. Most grades of Mobil1 are not suitable for extended drain intervals over those for any other API SL oil in an equivalent application.

Huw

nobody wrote in news: snipped-for-privacy@giganews.com:

I run Mobil 1 also and change oil and filter every 5,000 miles. Is it safe? I think so because it's slicker than conventional oil. I have a dirt bike (2 - stroke) that I run synthetic premix in. Usually I have to put a new top end (piston & rings) in once a year (yes, this is normal for a 2 stroke bike). Using synthetic premix I can easily go a year and a half on a set of rings. I verified this checking the ring gap not just by checking the compression.After this I was sold on synthetic oil.

I've been running 5000 miles between oil (Mobil 1) & filter changes on my cars, and had no problems with that.

My old Toyota gave me 240K miles of service on that regimen, didn't smoke or use any oil and _easily_ passed CA smog testing when I sold it to a friend. He put at least another 60K on it before he sold it to someone else.

Tom S

Sorry but I'm from the old school of thought and prefer the idea of changing it often. I like the 3k to 3.5k mile changes so I don't bother with synthetics tho I'm not against using them but don't like the idea of leaving oil in the auto longer than 3.5k miles per oil change. I've seen arguments pro and con about my thoughts so no flame wars need to start again but this is just my opinion based on my experiences. I do NOT claim to be an expert just a daily driver.

I've seen some earlier posts on 5k mile intervals for the synthetic and my guess is thats okay but regardless of my idea or others, it really depends what you drive, how you drive and where you drive.

Seems most synthetic oil manufacturers recommend a different (more expensive by 2-3x) filter when you use sythetics. Assume it captures smaller particles --- or is it just hype --- you paid more for the oil so will spring for a costlier filter. If you use synthetic oil but a cheap filter seems you should not extend change period?

You don't say what you're driving, the engine condition, your driving conditions, driving style, length of trips, weather, etc. All these make a difference.

Anyway, you can go the full drain interval shown in your owner's manual. Synthetic oil is good for longer drain intervals mainly because the oil itself doesn't break down as soon. Most of the contaminants in used oil (excluding fuel, antifreeze, etc.) are from breakdown or consumption of components in the oil. No need to worry about high priced filters; use any good quality one (probably doesn't come in an orange box).

If you have a lot of miles on conventional oil you might find increased oil consumption with the synthetic. That will go away after an oil change or two. Any and all oils leave some deposits in the engine. A premium oil with a superior detergent package will remove these deposits that in some cases may be doing some sealing. It'll take a short time for the new oil to begin it's own sealing process. If you have a heavily sludged engine (which you probably don't using Havoline @3k) you need a better engine cleaner. I've had good results with Auto-Rx

Ken

Ugh. Sorry. '99 Taco, 4 cyl, 5 speed. 80K miles. 90%+ freeway miles w trips being 50 miles+ round trip. Florida truck. Driving style: defensive.

Any info appreciated.

Mobil 1 10W-30 will work fine. You'll be good for the max length oil change interval shown in your owner's manual, and probably more after the first couple of oil changes where the new oil is cleaning things. If you do get some increased consumption on your 80k engine, add a quart of Mobil 1 15W-50 as make up oil until the consumption has returned to normal--then back to

10W-30 or maybe 5w-40 or 15W-40 in the Florida heat. Mobil 1 0W-40 is one good choice, as is Kendall or 76 5W-40, or Mobil Delvac 1 5W-40--"fleet" oil for gasoline and diesel engines.

Your oil filler cap probably says to use 5W-30, and your owner's manual probably recommends 5W-30 with 10W-30 allowed. Generally, 10W-30, having a lower content of viscosity index improver polymers, tends to shear down to a lower viscosity more slowly. You'll have slightly better engine protection toward the end of your drain interval with 10W-30. If you know the designation of your engine--four or five letters and numbers--you can look at the oil recommendations Toyota gives for other countries. Look at Australia's listings, because it has both English language and similar climate to your's (the U.K. listings are good for those in cool climates). You'll probably find that the same engine will have 15W-40 or 20W-50 recommended there. Other things equal, a higher viscosity oil will have a stronger oil film thickness. Too high viscosity will waste hp and way too high viscosity will not flow correctly into the bearings. Usually, an xW-40 is the maximum effective viscosity for most of us, with xW-50 for racing and certain engines that specify it.

Ken