What's the difference between synthetic and regular oil? Why can synthetic last up to 6,000 miles without having to worry about getting an oil change vs. a 3,000 mile? I heard synthetic is better. Any opinions/ facts guys? Thanks!

Synthetic oil does not breakdown as fast as fossil oil and it is more viscous, so it does last longer.

I'm not sure about the "why"...but I know synthetic is supposed to bond with the engine instead of draining out at shutdown. As I understand it, this makes for a better start-up because there is already oil in the engine before the parts get moving. If someone could please say this more eliquently I would appreciate it.LOL

I started using it at my first oil change.

Read up on Mobil One website but basically, synthetic oil molecules are all the same size. Dino oil have varied sizes. The smaller than average ones burn up in engine heat. This causes the brown burned color you see in oil which causes wear. If you put in synthetic, the motor will have less wear with time. If you plan on having it a long time, use synthetic. If you plan on selling in 4 years, don't. As far as time between changes, I still change every 3-5K with Mobil one but some blends are supposed to go to 30k between changes. I'm too old school to do that.
Last, you need to have the first oil change on dino so the motor will break in properly. It won't on synthetic. Then you can switch. You should not switch from dino to synthetic if you have more than 75k or so as you may have gasket seal problems. The dino oil works its way into the seals of the gaskets. The synthetic washes out the dino oil and you get leaks. ;)

As far as bonding goes, that's those oil additives like slick 50 that do that, not mobil one. You still basically have no oil at startup and should let it basically idle for a short period before driving each time you start for the first time each day.

Oh, and you need to get full synthetic. The synthetic blends like Castrol or Quaker State are useless wastes of money.

Last, you need to have the first oil change on dino so the motor will break in properly. It won't on synthetic. Then you can switch.
I should have said That I changed on the first one that I paid for. Dealer paid for the first one;) Hope my engine was broken in @ 7500miles:eek:

I changed to synthetic at 1500 miles on the motor, trans, diffs, and transfer case.

I changed to synthetic at 1500 miles on the motor, trans, diffs, and transfer case.

TB, what kind of synthetic (brand) trans fluild did you replace the matic j ATF with?

TB, what kind of synthetic (brand) trans fluild did you replace the matic j ATF with?
I think this was it.
http://www.mobil1.com/USA-English/MotorOil/Other_Products/Mobil_1_Synthetic_ATF.aspx
It is Dextron III, which is what Nissan says you can use as a substitute for their oil. I forget though as I didn't buy it, I had the Mobil 1 guys do it for me. ;)

I hear that once you go to synthetic oil you cant go back to regular oil. Not sure if this is true or not.

Nissan dealer told me that there is already synthetic transmission fluid in the tranny. Not sure if this is true either.

I hear that once you go to synthetic oil you cant go back to regular oil. Not sure if this is true or not.

Nissan dealer told me that there is already synthetic transmission fluid in the tranny. Not sure if this is true either.
You can go back and forth, but the gasket leak is the only problem I've heard. However, if you use dino oil with any frequency, it kinda defeats the purpose of the synthetic. As for the trans, I don't know. I just like to change out my fluids after breakin to get rid of extraneous metal shavings. ;)

I would NOT replace the transmission fluid with anything but Nissan J. That is the only one approved by Nissan. It clearly states in the owner's manual that Nissan will not repair/replace the transmission if anything else is used.

synthetic ftw! :D

This is where I was reading it from. Again, 2 years ago, I'm fuzzy. *8: For Canada, NISSAN Automatic Transmission Fluid (ATF), DEXRON™ III/MERCON™, or equivalent ATF may also be used.

See attachment from the Owner's manual.

See attachment from the Owner's manual.
Yeah, that was in the same section that I got the above from. That was bullet #5 and mine was bullet #8. Regardless, I'm not even sure if I did it or not. I'm sure I asked them about it, but if they don't have the correct stuff on hand, they won't do it. They don't want to be responsible for voiding warranties. But good info for everyone. ;)

Recently I have discovered the "Bob the oil guy" website. There is a wealth of oil related information there, almost too much.
http://www.bobistheoilguy.com/

There are also different levels of fully synthetic oil as well.

Mobil 1 and the stuff you get in the stores labelled full synthetic is the "level 1" However Royal Purple and some of the more expensive Amsoils are "level 2" synthetic.

I use the Amsoil 30k oil and change it about every 10k miles.

The key is to get a quality filter because most oil, even dino oil will last 5k+ miles, however the filter stops filtering if it's a cheapo.

As for Trans, I'm sticking to the Nissan stuff, letting my dealer drain and fill it every 20k miles.

Transfer case will get Amsoil Synthetic ATF, and Amsoil Synthetic will go in the front and rear diffys as well.

-mike

I posted this in another thread, but I'll ask again--

Are there other factors that one should consider with the Mada/QX? Does the large, heavy-duty nature of the vehicle suggest mineral more than synthetic? Or if you do heavy towing? What if the vehicle is used in very cold weather?

I posted this in another thread, but I'll ask again--

Are there other factors that one should consider with the Mada/QX? Does the large, heavy-duty nature of the vehicle suggest mineral more than synthetic? Or if you do heavy towing? What if the vehicle is used in very cold weather?

Good question. You mean very cold weather like where we are going. BRRRRRRR.

I hate to wake up an old thread but.....

Is there really a benefit to additives like slick 50?? And do they really stick and help at start up?? Also what filters seem to be best? I hear god things about wix.

I hate to wake up an old thread but.....

Is there really a benefit to additives like slick 50?? And do they really stick and help at start up?? Also what filters seem to be best? I hear god things about wix.

sadly no, there is no real benefit. it's all in the marketing. i prefer amsoil filters myself.

I just use a synthetic oil specific filter. That's about it. By the time you are choosing different filters, you are really splitting hairs. :whip: