I just bought a new 2003 Pathfinder, and can't help wondering why the owner's manuel recommends that you not use synthetic oil? Every thing I ever read says that synthetic oil is superior to conventional, fossil fuel oil. Does anybody have any information on this? Will synthetic oil damage the engine or something?
I just bought a new 2003 Pathfinder, and can't help wondering why the owner's manuel recommends that you not use synthetic oil? Every thing I ever read says that synthetic oil is superior to conventional, fossil fuel oil. Does anybody have any information on this? Will synthetic oil damage the engine or something?
There are many reasons to recommend or not recommend synthetic oil. Nissan knows that synthetic oil is simply not necessary with a vehicle such as a Pathfinder. The vehicle probably has an oil cooler, which REALLY negates the need for the high temperature resistance of synthetic oil. You'll never get your oil hot enough for a quality conventional oil to start thermally breaking down. There are also other factors, such as seal material. Some seals are not really compatible with synthetic oil (meaning they may fail or leak). Some of the seals in your engine are probably prone to leakage if you run synthetic oil. I'm not privvy to the details with the design of the engine, but that statement was added to the owner's manual for a reason. I'm just throwing out possibilities.
Doesn't the VQ35DE have variable valve timing? A premium domestic brand switched to recommending Mobil 1 oil (and changed the engine seals to match the new recommendation) after switching to VVT because the synchros in the VVT like the slightly more stable synthetic oil. They went from recommending AGAINST synthetic oil (because of the incompatible seal material and the unnecessary cost of the synthetic oil) to recommending ONLY Mobil 1 synthetic with the redesign of the valvetrain. I'm surprised that Nissan specifically does NOT recommend synthetic, especially if the engine has VVT, but there's a reason for them recommending against it and I'd certainly follow the recommendations if it were my vehicle.
that's interesting... after reading your post I freaked out and looked through my owners manual again since I have used Mobil 1 since 5k miles and it says no where in my manual about not using synthetic oils... in my frontier manual it just says to use mineral based oils (which even synthetic oils are mineral based) and my nissan dealer has yet to say otherwise since I take it to them and provide my own 5 quarts of Mobil 1 (you can get it the cheapest at Wal-Mart).
Yes JadCock the 3.5 motors all run CVVT (continuous variable valve timing) but I agree with you that since the cams switch phases it would demand a higher performance oil like a synthetic. I would definitely ask the dealer. If take the car with synthetic oil to them and they refuse to put it in, I wouldn't.
Later,
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Black Knight - 2004 Crew Cab XE-V6 4x4
"...God made men the way they are because we desperately need them to be the way they are. Yes, a man is a dangerous thing, but so is a scalpel. You don't make it safe by making it dull, but instead you put it in the hands of someone who knows what he's doing." - John Eldridge
There are lots of myths and misconceptions about "synthetic" oil and even the name does not necessarily mean what you think it might. For example, most "synthetics" sold today are merely highly processed mineral oils ... marked up well beyond what they are worth.
Early synthetics (mostly PAO, made mostly by Mobil) had seal compatibility issues as the PAOs tended to leach plasticizer out of the seals, hardening them and causing them to leak. This was 15+ years ago. Modern syntheics are carefully formulated to be "seal-nuetral" and mimic the behavior of typical mineral-based oils.
Besides most, if not all, of the mass-market synthetics have converted to these highly refined "Group III" mineral base stocks. The term "synthetic" has been proclaimed a marketing term and NOT a technical one.
Your manual is wrong as it is promoting old myths. I doubt your dealership will be any more helpful. If they are, it's probably just an accident.
Do a search on this site (the ENTIRE site) using the word "synthetic," and you'll find a lot of good discussion about oils and lubricants.
(Just don't use a synthetic oil and figure you can go 20,000+ miles between oil changes. It's just not that simple, regardless of brand and claims).
Not sure about the new ones, but I have been running Mobil1 in my 95 KA since it was new. It still runs like new and even after 3 months the oil looks remarkably similar to when I put in. As far as how I drive, I explore my valve springs 5500 rpm float limit daily. I also do a daily run up the hill at work at WOT that is about 1/2 mile up an 8% grade. I can get 58 MPH in second. So, yeah, I drive it like a rental. It still purrs like a kitten. I did notice a little seepage around the seals after putting it in the first time, but it is an evil I can deal with. How long ya plan to keep the truck?
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Aaron Ford
95 2WD Nissan PU E
2002 Oldsmobile Intrigue GX
"The hard part about playing chicken is knowing when to flinch" Scott Glenn in The Hunt for Red October
Thanks for your input. I can only speak from one experience, but when I switched from Castrol to Amsoil at about 12,500 miles in my 2001 Jeep Cherokee, my miles per gallon immediately increased from about 16.0 mpg to about 18.0 mpg overnight. I did not know that synthetic oil was mineral based!!! I figure on driving this Pathfinder for probably at least 10 years.
I figure on driving this Pathfinder for probably at least 10 years.
My truck is 8 years old with 135,000 miles. I’ve owned it since 2000 when it had 58,000 miles. I use Mobil’s Drive Clean 5W-30 and either a Nissan or Purolator oil filter. I change the oil and filter every 3,000 miles and I tow an 18’ ski boat in the hills of PA a lot over the summer. My engine runs great and with the exception of a weeping camshaft oil seal never looses or uses a drop of oil. Is synthetic really worth the extra money? Yes, I am sure that the synthetic will outperform my dino oil, but the real question is do you need anything better than dino oil.
Yes, I am sure that the synthetic will outperform my dino oil, but the real question is do you need anything better than dino oil.
That's really the bottom line. With 182k miles on my KA24E (to be fair, I've only owned it since 171k), 127k miles on my Northstar Cadillac, 133k miles on my '84 Cutlass when I sold it, 165k miles on our 4.0L Cherokee when we sold it, all fed a constant diet of conventional oil, my personal opinion is no way. And to get down to the nitty gritty, if you never start your engine in weather way below zero, if you never run oil temperatures way above 300*F, if you have a "simple" engine like one with a conventional valvetrain, I honestly believe that "synthetic" oil offers no benefit over conventional oil, because you're WELL within a conventional oil's protection capacity.
To me, it's like brushing your teeth 20 times a day. Is that better than brushing them 3 times? You could probably argue that it is. Are you still cavity free if you brush good after every meal, only 3 times a day? Of course!
[i]"To get down to the nitty gritty, if you never start your engine in weather way below zero, if you never run oil temperatures way above 300*F, if you have a 'simple' engine like one with a conventional valvetrain, I honestly believe that 'synthetic' oil offers no benefit over conventional oil."
I basically agree. With synthetic oil, whether it is Group III mineral, Group IV PAO or Group V ester, the most significant benefit you get is the ability to flow in extreme temperatures and over time in the crankcase. This has very little to do with wear protection. Superior wear protection comes from the quality and type of the additive package.
Now synthetic oils, with their significantly higher price, may offer a superior additive package but that's not always the case. The SJ Tri-Synthetic version of Mobil 1 had an EPA-friendly WEAK additive package and produced some crappy oil analysis. This was corrected with the SL versions of that oil as well as most batches of Super-Syn.
You can also get specialty conventional oils and synthetic BLENDs from a companies like Schaeffer Oil which are mostly Group I, II and II+ base oils ... but with top quality additive packages.
But even Chevron Supreme, an incredibly inexpensive oil, has a high-performance additive package with moly and boron and produces incredibly clean engines and low wear rates.
But even Chevron Supreme, an incredibly inexpensive oil, has a high-performance additive package with moly and boron and produces incredibly clean engines and low wear rates.
That's what I plan to run next time I change the oil. What have you guys seen regarding viscosity breakdown of this oil? When I used to run Valvoline in my truck, it seems that I had more mechanical noises and nuances after 1000 miles or so than I had soon after I changed the oil. I bet it was breaking down and turning into a thinner oil. Mobil Drive Clean doesn't do that for me...the engine stays quiet until I need to change the oil again (I usually run close to 3000 miles nowadays). But I understand Mobil Drive Clean oil doesn't have much of an additive package, so I plan to try the Chevron next time.
"What have you guys seen regarding viscosity breakdown of (Chevron Supreme)?"
Seems pretty stable, even the 5W30 out to 4,000+ miles ... and the 10W30 should be more stable still. If you go to the "Used Oil Analysis - Gas engines" subsection, you can search for tests yourself. Use the phrase "Chevron Supreme" and look at at least 3-4 tests. Skim through the (mostly positive) comments and get that warm and tingly feelin' inside. There is one exceptional Nissan ... maybe a pick-up? I guess i'll have to do a search myself.
Chevron 10W40, however, is a 30 weight by the 4,000 mile mark. This is an obsolescent weight anyway, and it seems it's probably 10W30 with a little more (cheap/unstable) VII in it.
I would have said the same glowing comments about Pennzoil (which uses a top-notch Group II+ base oil) but one very recent example showed some thinning. The reason still has not been determined. I'm not ruling out lab error ... or at least fuel dilution which was not posted. I need to stir the pot a little on that one.
"When I used to run Valvoline in my truck, it seems that I had more mechanical noises and nuances after 1000 miles or so than I had soon after I changed the oil. I bet it was breaking down and turning into a thinner oil."
Yes thinner ... and the additive package might have been less-than-fresh. And Valvoline All-Climate has probably the weakest add-pack I've ever seen and it seems to me that the add-pack is what keeps engines quiet. I know it seems to be the key to minimizing piston slap noise ... ticking or knocking at initial start-up in cold weather.
"Mobil Drive Clean doesn't do that for me...the engine stays quiet until I need to change the oil again (I usually run close to 3000 miles nowadays). But I understand Mobil Drive Clean oil doesn't have much of an additive package, so I plan to try the Chevron next time."
Odd. Mobil DC has had mixed results on the board. Anyway, you should be very happy with the Chevron Supreme.
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--- Bror Jace
Last edited by Bror Jace : Jan 24th, 2004 at 08:41 PM.
And this one is a Nissan Frontier KA24DE driven about 100 miles per day. The great thing about this link is that JohnK posted several sequential results using the same oil. In the last one, you can see the change in the additive package as moly and boron were added to the Chevron Supreme formula:
Last winter, when I first got the truck, I was using Valvoline All-Climate. I used it for ever in my domestic V-8s, and figured it'd be just fine in the truck too. It would tick and tap a lot on a cold start and I never could figure out why. It was pretty intermittent, and not a constant noise.
Fast forward to this past summer, and I started looking at the Mobil DC on the shelves. Figured for about a buck a quart at Wally Mart, I couldn't go wrong with that stuff. Mysteriously, the noises STOPPED!! I was really dumbfounded, because I'm the kind of guy who believes motor oil is motor oil. I was using Valvoline only because I pull for Mark Martin on the NASCAR circuit and he was sponsored by Valvoline for the longest time -- I had no other affiliation with Valvoline, and in my mind, no reason to switch to another.
Maybe my Nissan engine is worn just enough where the additive package does make a difference in the noises from the engine. I still think it's unacceptable -- my domestic engines are quiet as a kitten, both pushrod OHV and DOHC 32-valve V-8s with well over 100k miles. But I can't really blame my problems on Nissan because I don't know how well it was maintained earlier in its life. But similar comments from many other 4-cylinder Nissan owners (and experience with a particular GA16DE-powered 200SX) leads me to believe Nissan's valvetrain designs are just noisy.
Anyway...that's beside the point...yes, I plan to fill with Chevron Supreme this next time. My Caddy's down to 46% on the oil life monitor...and my Nissan's at leat 1500 miles on its change, so I guess it's time to get a case today while I'm out.
“… when I first got the truck, I was using Valvoline All-Climate … It would tick and tap a lot on a cold start and I never could figure out why. It was pretty intermittent, and not a constant noise. Fast forward to this past summer, and I started looking at the Mobil DC on the shelves. Figured for about a buck a quart at Wally Mart, I couldn't go wrong with that stuff. Mysteriously, the noises STOPPED!!”
Diagnosing engine noises is a lot like Chinese tea reading of the future … or looking at Norse bones & antler chips and trying to predict the weather. Hard to be sure when you stick your head under a hood … let alone a thousand plus miles away.
BUT, most cold-weather noises are attributed to what’s called “piston slap.” Manufacturers are trying to make pistons lighter to bump up their engine efficiency/power numbers a touch. To do this, the piston skirts are shorter and the piston tends to ‘rock’ back and forth in the cylinder during the cycle of the stroke. This makes the knocking or ‘slapping’ noise until the engine warms up and the piston expands. This can either be from wear or hammering deformation … or both.
There is an alternative theory that piston stroke is caused by wrist pin wear and excessive play but I’m not familiar with it enough to explain it properly.
In either case, it appears that a strong/fresh barrier anti-wear package does the most to quiet this down. I first started noticed this when I went from Mobil 1 Tri-Synthetic to Red Line Oil in my high-mileage Civic and the cold weather knocking noise virtually disappeared. A friend had an even higher-mileage Civic running on Mobil 1 and he switched to the original Valvoline Max-Life formula. Same thing occurred. What do these oils have in common that Mobil 1 doesn’t? Molybdenum … and lots of it: 200+PPM. Since then, most PCMOs (Passenger Car Motor Oils) have added molybdenum to their formula to compensate for EPA and API mandated lower levels of zinc and phosphorous. But this is usually in relatively low amounts, like 50-100PPM. Mobil 1 also uses molybdenum in their latest SuperSyn formula as well as Boron which has a similar function. Amsoil still uses lot of ZDDP (zinc & phosphorous) in their formulas which are not API certified.
Some people claim they still get a lot of noise with Mobil 1 SS, especially in cold weather, but might be because it’s formulated on the thin side. Not everyone agrees on what causes the noise … and so many engines are different. At least their barrier package
“I'm the kind of guy who believes motor oil is motor oil. I was using Valvoline only because I pull for Mark Martin on the NASCAR circuit and he was sponsored by Valvoline for the longest time -- I had no other affiliation with Valvoline, and in my mind, no reason to switch to another.”
Been there, done that. I broke my ‘95 Civic in using All-Climate. I liked all the racing they sponsored and I was under the impression they refined their own PCMOs. They do not. However, now I know better and prefer other brands.
“Maybe my Nissan engine is worn just enough where the additive package does make a difference in the noises from the engine. I still think it's unacceptable -- my domestic engines are quiet as a kitten, both pushrod OHV and DOHC 32-valve V-8s with well over 100k miles.”
And most of those (older) domestic designs will have longer piston skirts ... and probably more sound deadening mass in the motor in general. I’ve heard of some slap-happy late model Fords. Not sure which ones, though. You could try a search of all of BITOG using the phrase “piston slap” to see discussion on this. There are a handful of decent threads in the “Mechanical Tips & Tricks” sub-section alone.
“But I can't really blame my problems on Nissan because I don't know how well it was maintained earlier in its life. But similar comments from many other 4-cylinder Nissan owners (and experience with a particular GA16DE-powered 200SX) leads me to believe Nissan's valvetrain designs are just noisy.”
That may be the case … and it may or may not be a design defect. Hondas live with piston slap for many tens of thousands of miles. As for previous owners, I scope out inside the valve cover signs of sludge … but usually avoid buying used altogether.
“I plan to fill with Chevron Supreme this next time. My Caddy's down to 46% on the oil life monitor...and my Nissan's at least 1,500 miles on its change, so I guess it's time to get a case today while I'm out.”
Good deal. It has both moly AND boron, the best additive package I’ve ever seen in a conventional oil … and it seemed to do pretty well even before! The stuff is cheapest at places like WalMart or Costco but if you see a new product or an odd weight of theirs you’d really like to try (heard about it in a forum or saw it on their website) it probably won’t be available at one of those discounters. Consider looking up “Oils-Lubricating” in your yellow pages to find a local Chevron distributor. I never knew this area had one until I looked it up.
If I recall correctly from the BITOG forum, the Chevron Supreme is exactly the same stuff as the Havoline, is that correct? Only reason I ask is because Walmart is the ONLY source I've found for the Chevron Supreme and they don't sell it in cases. Vice Havoline, which is available by the case everywhere, including Walmart and Sams, so I can price-shop to find the lowest price for the same oil.
I tried to find the thread I was reading but couldn't. I hope you'll know off the top of your head.
And to get down to the nitty gritty, if you never start your engine in weather way below zero, if you never run oil temperatures way above 300*F, if you have a "simple" engine like one with a conventional valvetrain, I honestly believe that "synthetic" oil offers no benefit over conventional oil, because you're WELL within a conventional oil's protection capacity.
