I personally gained a few miles per gallon when I switched to synthetic in both of my 4runners. so the difference in price was worth it to me.

 

I had some engine chatter, sounded like knocking or valve slapping, not sure what it was bc the switch to full syn stopped it within 75 miles. that was in my Xterra, havent done the switch in the runner yet, gonna seafoam the hell out of it when i change it.

as for amsoil, i recommend using it only for tranny/gear oil, and i recommend redline for the engine, though i still use mobil even though it only a group 3 motor oil, it readily available, and while amsoil is a group 4 and redline a group 5,
they are more $ and in most cases must be ordered. ive priced redline at 8.99 a qt and as low as $7.49qt

 

amzoil is suppose to last 30,000 miles. and be the best there is out there

 

That is true, but it's more expensive than M1 and you can't get it at AutoZone or WalMart. Convenience is important to me.

Rob

 

I'd never go over 15k on any oil period since I wouldn't trust it. If I waited to 30k miles it would take me about 3 years and by then the oil will have accumulated alot of garbage and will become acidic over an extended period of time.
Amsoil is good but not that good and IMO it's not worth the hassle to obtain when M1 is available 5 minutes from me.

 

Royal Purple is supposedly better than Amsoil. But again, I don't think anyone's done a complete, long-term analysis between them.

 

I've preached on this subject for years! I'm going to guess that due to the year of your vehicle, you have 130k or higher miles. My Taco has 131k! Anyway, the main purpose of synthetics is to remove and bind to any and all harmful deposits left behind by engine friction (basically, clean things up). Also, due to the age of your runner, the seals may not be the best either, and the lighter synthetic oil may leak? This is on a case-by-case basis, and doesn't happen to everyone who may make the switch. A lot of people don't like having to change the oil every 3k, so they go with a higher mileage synthetic or dino, and wait to change it every 5k-10k. I personally keep a record of oil changes in my glovebox, and when I'm at 3k, it get changed without question or delay. I use Valvoline 5W 30 in my 2.7L, and have since I've owned this truck (4 years - second owner). If it ain't broke, don't fix it! The long and short of it is, just keep the oil clean, change it every 3k, and you can't go wrong.

 

amzoil recommends to change it at least once a year

 

I figured there was a time interval.

I switched to synthetic on both my '97 Runner ( 86k in '03) and on my '99 (97k in '04) and while I don't know what's up with the '97 my '99 has had nary a leak and is perfectly fine and uses a negligible amount of oil every 9000 miles and I've got 130k on the truck now.

 

IMO, not worth putting in a 22RE or the 3.0. Regular old Castrol GTX and regular changes are perfectly fine for it. Full synthetic if I had a newer 3.4 or V-8.

 

I switched my 3.0 over to partial synth about a year ago, right about 153,000 miles. Never have had a leak. Asked my shop (they only work on Toyotas) about full synth, they said stick with the partial. They said there is a benefit to using it for high mileage but to switch to full synth wasn't worth the extra cost. My .02.

 

A quote direct from the Mobol 1 site:

"Conventional oils come from crude oil that is pumped from the ground. Crude oil is made up of a twisted and jumbled mass of carbon atoms that form chains and rings of different sizes and shapes. Long chains of carbon atoms produce a thick viscous fluid that flows slowly. Shorter chains produce fluid that flows more readily.

In an oil refinery, crude oil is separated into various stocks. These become the basis for lubricating oils and fuels. Thick tangled masses of carbon chains become asphaltic materials used in roofing tar and road work. Very short chains and ring compounds of carbon are volatile and can be refined to produce gasoline and other solvents.

While petroleum refining is an advanced science, small amounts of contaminants, such as sulfur, wax and asphaltic material cannot be completely removed from petroleum, and may end up in motor oil base stocks.

More than 30 years ago Mobil began looking for lubricants that would flow easily at extremely low temperatures. This search led to the development of synthetic base fluids free from the waxes and contaminants that cause conventional lubricants to solidify in extreme cold. The result was the development of Mobil 1, a fully synthetic motor oil created, initially, from two synthetic base fluids – polyalphaolefins (PAO) and esters combined with a unique additive package.

PAOs are made by chemically knitting molecules of ethylene into carbon chains of uniform length and shape. These carbon chains can remain liquid and slippery under the widest range of engine conditions possible. The PAOs are combined with an ester – a compound formed from the reaction of alcohol and certain acids. The resulting synthetic fluid provides the optimum performance properties for engine lubricants.

Ultimately, Mobil developed an additional synthetic base fluid – an alkylated aromatic – that is especially effective in protecting engines against wear, sludge formation and piston deposits. This new formula has been incorporated into Mobil 1 Tri-Synthetic™ motor oil, which was introduced in 1999."

 

Even though this subject has been discussed countless times, I had to stop and think about the obvious.

If synthetics can last longer, tolerate higher and lower temps, and have proven to provide more protection under such extremes then it should be evident which is better at lubricating.

The only question left after that is does one consider it worthwhile to spend the money on their vehicle.

15w-50 M1 (extended life/15k mi) is $6.99/qt x 5 (a complete oil change)=$34.95
Plus, three (must change them at intervals) WIX oil filters (let's use a good one) at $5.29ea = $15.87
Plus, three extra qts. to top off when necessary = $21.07
Total=$76.89

O'Reilly house brand 20w-50 = $1.79/qt X 5 = $8.95
WIX filter...again...=$5.29
Plus, extra qt.=$1.79
Total (complete oil change)= $16.03

BUT, multiply that times 5...the amount of times you have to change to equate with the M1 drain interval = $80.65

So, M1 = $76.89
O'Reilly dino = $80.65

I'm going by a healthy motor (barring repairs, accidents, etc.) at what the average typically consider maintenance.....like me! One can also count in odd variables which cost would then have to be adjusted, but as you can see there's really not a big difference in price.

 

Nicely put!

I've thought about the whole synthetic thing and would probably do it on a new 4-runner if I was lucky enough to get one but I've made it with no problems through 170,000 miles religiously changing the oil at 3k sometimes 2.7k! So I'm gonna stick with if it ain't broke, dont fix it.

 

There is no question that synthetic oil is a better lubricant than conventional oil. It's a fact actually. Weather you would actually need it or not should be the question. For the average person who drives on the freeway for long periods of time, synthetic (while a better lubricant) is unnecessary and would be costly. For the average soccer mom who drives in stop and go traffic constantly and starts and shuts off their engine a lot of times in the day and is neglectful on their oil change interval, synthetic would definantly be a better choice. I guess you really need to figure out where you fit in and decide what's better for you. I like the fact that synthetics withstand high temperatures and oil break down better than conventional oils. I am not easy on my engine by any means. I go to the 115 degree desert on a regular basis with a 280K 22RE on Mobil 1 10W/30. I would never ever dream of letting the oil go for 15K without changing it. I don't care if it is designed for it or not. I usually don't even make it 1500 between oil changes. I am extremely anal but my odometer doesn't lie and internally, the engine is beautifully clean with the valve cover or the oil pan off.


For all the 15W/50 and 20W/50 users:
Where is the advantage of using molasses? I am just curious on what would posess someone to use a thicker oil than 10W/40. If the rods knock, replace your engine. Thick oils do more harm than good.

 

I used 20W-50 for over 6 years, with no discernable harm. If you run the engine hard in high heat conditions, it will keep your oil pressure up. I've read that higher viscosity oil is better for bearings/lower end due to it's higher shear strength, but doesn't lubricate the upper end as well. However, my cams were in outstanding shape during my recent rebuild @ 218,000 miles (Head Gasket). In fact, the entire engine had practically no wear, including the cylinder walls.

 

Well I just changed the oil in my '86 recently and I used Valvoline 10w-40 and a motorcraft oil filter for an older ford 5.0 (its a bigger filter) and I've been doin that for a long while now... I get the filters fo' free from my uncle since hes a dealer or whatev he gets so many extras.. I've heard all the rumors about synth. oils but I think engines can last 300k on dino oil so why ☺☺☺☺ with it.

 

5 qts plus 1 for good measure of M1 syn at wallyworld = $28
Puralator PureOne filter = $6

$34 every 8-9 months for me plus I spend only a half hour of my time doing it in that time frame. I'll never go back to dino oil period.

 

That's assuming a used oil analysis shows you can really go 15k miles. I would NEVER take any of these manufacturer's word about the interval. The ONLY way to justify extended drain intervals is a UOA. (same thing applies for dino oil too BTW)

 

I couldn't go 15k even if I put it those miles on quickly. I usually change it by 8k but procrastinating for another 500 or so doesn't worry me with synthetic.