Smart idea to switch to synthetic oil?

[Qxxx4]

ive got just over 100,000kms (64k miles) on my 99.5 qx4....I baby this thing. My concern is that it does burn a little oil, and i hate to make any drastic changes.....would you guys think this is a good idea? is there ANY chance i could encounter any problems? Im changing oil this weekend at mr lube, and if you guys suggest it ill dish out the extra cash for it. My dads land rover runs synthetic, its awesome, more money i know but im sure it increases longevity of your car...is this true even with the mileage i already have on mine? and i know the intervals are different, the land rover is something like every 12000 kms....same for qx4 right? Im very interested in your opinions! thanks!

[Buzzman]

Not sure I'd do it at this point. Too many miles in my opinion. It would probably increase your oil consumption. Maybe try switching to a semi-synthetic first and see how it performs.I run synthetic, but I started the day I bought the truck. I also change mine earlier than 12,000kms. I seldom run past 7,000kms on a change.Any other opinions folks? I know we've had this discussion before on this forum, with lots of different ideas. Let's have it.

[Qxxx4]

yeah i read that other post, its a 50-50split id say, I dont think i want to risk it, maybe ill run semi-synthetic for the next 2-3 changes, see what happens. If theres any chance of problems i wont do it!

[Pathfinder995]

I strongly disagree with the opinion that says it's too late in the ballgame to switch to synthetic...you will probably have some leaks as a result of switching but change the valve cover gaskets and be on with it...it will reduce wear on your engine and in my opinion will not cause adverse effects but rather benefit you in the long run.

[02pathy]

if it already burning oil all u are going to do is burn even more oil, you can still try it but buy an engine flush from amsoil and run for it 20mins at idle b4 the oil change put in the synthetic and keep an eye on it if burning too much try using a half bottle of lucas synthetic oil stabalizer it might help, i usally use the regular 1 in my car and it helps

p.s: i woulds stronly recommend putting a half bottle of lucas b4 the synthetic just so u get the right amount it there

[slickroger]

i bought my truck at 150,000 km and i switched to synthetic, but i wasnt burning oil. to tell you the truth after i rolled my green pathfinder last november and it had a minor oil leak. i went shopping for another pathfinder, i checked about 10 or 11 and the one i bought was the only one that didnt have any oil leaks what so ever. is there an additive or some sort of sealant i can use to prevent future leaks cause i can definetly see it coming.

whats the word on the street

[bmlawless]

Let's start by saying that the only thing I know about synthetic oil is from the towing/hauling world. Over there we discuss the high heat tolerance and longevity of synthetics. Their ability to retain viscosity and heat sink properties at high temps make them perfect for protecting the engines of vehicles that routinely haul camper, boats, 5th wheels, etc. I've never heard anybody talk about increased leaks or consumption.

That being said, if I truly felt that synthoil would do a far better job of extending the life of my engine, I think increased consumption and a few more drips on the floor in the garage would be worth adding more life to the car. It seems like the older a vehicle gets, the more it needs the protection of a superior lubricant.

[slickroger]

I couldnt agree more

Thats the word on the street

[fueler]

My opinion is that using regular dinosaur oil every 3k is less expensive than changing synthetic every 5k miles.... These Nissans are so reliable that i dont think we need the expensive stuff.... But i'm sure synthetic has slight benefits in terms of MPG, sound, ability to withstand extreme heat, etc

I switched to synthetic in my Honda Civic and it started burning oil, but it never physically leaked on the ground or anything.... it seemed as if it ran the same as dinosaur oil, now i prefer to keep the cheaper dino oil in my QX4

[justjuiceit4]

Let's start by saying that the only thing I know about synthetic oil is from the towing/hauling world. Over there we discuss the high heat tolerance and longevity of synthetics. Their ability to retain viscosity and heat sink properties at high temps make them perfect for protecting the engines of vehicles that routinely haul camper, boats, 5th wheels, etc. I've never heard anybody talk about increased leaks or consumption..

It is true that synthetics have higher heat tolerance, but IIRC, newer engines(2003-up VQ) use different bearing materials that are less heat tolerant. So, the synthetic oil may be retaining all the properties at an elevated temperature, but the bearings are taking a beating. My towing experience has let me to believe that if you have a large oil cooler than the temperature stays at normal levels and synthetics are not needed.

[Qxxx4]

all very good points, Im thinking of maybe just going sem-synthetic always then? it may be a little more money but ill get the best of both worlds maybe? Im guessing I could do the change every 5000kms as conventional oil, and still have the advantages of sythetic....somewhat, and not have the price and problems that could arise with full synthetic. Im going for my oilchange today and i think ill do the dinosaur oil one more time then switch in the spring to semi synth and take things from there. thanks for your opinions, all very good points

[Greybrick]

Synthetic is really just a word meaning processed. What type of processed /synthesized base oil were you planning on using; group III hydrocracked, group III gas to liquid, group IV PAO or group V ester and if group V were you thinking of using a diester, polyolester or larger molecule complex ester oil? None of these are purely one type of oil though as they are all blended with other types of oils, polymers and even silicone to carry friction reducers and detergents and mix with viscosifiers.

They all have similar properties but a couple of them have lower friction coefficients and depending on grade some have pour points down to -75 F degrees. One of the best properties of well designed synthetic based oils is that they stay in grade longer because they don't mix with the small amounts of combustion water generated and turn into sludge in your engine. Some synthetic oils can reverse some or all of the effects of varnish and sludge build up of previously used mineral oils.

Auto RX is a synthetic di-ester oil based engine cleaner that can get rid old mineral oil varnish, sludge and carbon build up quickly so that you can restart with an efficient synthetic oil which won't be getting diluted by contaminates. Unlike kerosene type engine cleaners which dissolve varnish and sludge, di-esters due to polarity attach themselves to engine metals and displace contaminants, so actually clean right to the metal surfaces.

http://www.auto-rx.com/

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Modified by Greybrick at 8:29 AM 2/9/2008
Modified by Greybrick at 10:40 AM 2/9/2008

[Qxxx4]

greybrick, i feel like im in grade 12 chemistry again lol YOU KNOW YOUR STUFF! are you a chemist or something? I am hands down sold that synthetic is GOOD for your engine in the matter that it cleans up that buildup (and my engine does have some buildup) and i think im going to go semi synthetic, ill ask if they can do it, if not i will wait the 6 months left on my crappy lubrico warranty then do the oilchanges myself and use synthetic. Thanks alot for your valuable knowledge and advice, everyone!!

[Pathfinder995]

I said it earlier - I'll say it again...if you see leaks as a result from switching to synthetic, change your value cover and oil pan gaskets! I know that in the VG engine those are the main places you'll see a leak - not sure about the VQ. In any event, even if you can't do the repair, it's worth getting those done. Then use the Amsoil engine flush like somebody mentioned earlier, change your oil and you have a brand new engine.

Re: cost...Mobil 1 is available at Wal-Mart by the gallon and case and it's cheaper than Amsoil as far as retail goes. I know a guy who sells Amsoil to me at his cost (he's a distributor) so I have the hookup and price is not an issue, but if it is, buy Mobil 1 at WalMart and be on with it already.