47000 miles-is it ok to switch to synthetic oil?

sr20speed · Apr 15th, 2003, 09:15 PM

My 96 200sx SE-R has 47,000 miles on it. Is it ok to switch to synthetic oil or will my engine start to leak like crazy. Also, I know this topic is well covered but is mobil-1 or motul oil better?
And should I get 5W30 or 10W30 or what?

BORNGEARHEAD · Apr 15th, 2003, 11:39 PM

Yes it is ok to use it. I recommend 5w-30. You are not going to start seeing leaks from Mobil 1. My motor actually ran quieter when I switched to Mobil 1.

onyxeros · Apr 16th, 2003, 10:33 AM

yes it's ok
5w-30

O

lowmileage · Apr 16th, 2003, 12:46 PM

Do what the owners manual says. I know for the '91 SE-R it says 5w-30 and it was hard for me to follow initially bacause I've used 10w-40 in my Chevy V8's. You need the light wt to flow quickly because that is where the most wear is caused - upon start up.

SangerSE-R · Apr 16th, 2003, 02:22 PM

5w 30 is not that good, use 15w30, my mechanic said my motor is making metal hitting metal noise with 5w30. So next oil change I"m going ot 15w30. What do you guys think? Oh yeah, never, never, ever use Penzoil or however it is spelled. My engine has 147k on it though, so maybe I need 15w30 now

OZMAN · Apr 18th, 2003, 07:35 PM

I use 10w40 amsoil with 88 thousand miles runs great.

PrimeraP11 · Apr 23rd, 2003, 10:45 PM

guys you can put the oil that you want but always have in mind that those number have a reason, the first one is for winter time that why it has a W chek your local temperature, them pass from F to C grades, and you have the lower number.

For the higher one find the temp to but this time higher one, and do the convertion.

example

15w-40

15 grades oC and 40 C if you drive your car on those weather temperature your just fine
And yes Mobil is the best oil , no Castrol< no Shell, i work on transport vesels and that oil is the best by analisis that engineers do here, and from japan, also a have been on 3 sr20de, one on a bluebird, and 2 on a primera is the best, go for it,
One sugestion, its bad to go synt and here the reason.

The mineral oil develop a film on your piston carbon that mixed they seal.
When you put a change of oil over from mineral oil to synth, the synt will clean your deposit of carbon, that way make your engine smoke
and you know what hapen when smoke. This was an explanation from a Engineer that work at Mobil. An is true, i have heard several old car p\dump theyr engines to ttrash for the oil change.

samk · Apr 25th, 2003, 02:17 AM

the issue isn't switching to synthetic that will cause problems...when you switch to synthetic, don't go back. not exactly sure why but engines don't like that. if you're in California, 5W30 is optimal according to manufacturers.

Apr 27th, 2003, 04:42 PM

ya sure switchin it up is cool, but synthetic will dissapear real quick even if you have the tiniest leak, it flows like crazy.....

cademetz · Apr 30th, 2003, 11:38 AM

I switched my 96' SE-R to Mobil1 at about 55K miles. Car has near 100K... not a problem in world.

bullfrg · May 5th, 2003, 01:27 PM

I switched my 92 SE-R to Mobil 1 right after I bought it with 54,000 miles on it. It now has 117,000 and no real problems. I did have an oil leak at my oil sending unit when I had about 110,000 miles on my car, but this is pretty comman.

sr20speed · May 5th, 2003, 11:07 PM

Thanks everyone. I already changed to 5W-30 Mobil One.

INX2C · Jun 3rd, 2003, 08:56 PM

What the heck. Here's my oily input.
Synthetic oil is good for lots of reasons. Five big ones come to mind right away. 1) decreased friction; 2) Boundary lubrication; 3)runs & pumps at sub-zero temps; 4) resists molecular changes @ high temps & loads (ie: breakdown); 5) ZERO sludge formation.

What it does NOT do is do away with the normal reaction that happens in the cylinder when your gas burns. So lots of little corrosive things get left over on the cylinder walls and eventually wind up in your oil. This means that while synthetic is amazing, you still have to change it. 7 - 10,000 miles is OK with high quality oil.

To imagine the difference between synthetic & conventional oil, picture a bunch of kiddie marbles on the floor next to you. These are oil molecules. Conventional "marbles" will be several different diameters & colors. Synthetic will be identical diameters and just a few colors. Because synthetic molecules are consistant, we get one of the best properties - boundary lubrication. That means that a film of oil molecules stays on all your top-end parts when you shut down at night. In the morning, when you fire up, there's already some protection before the regular oil flow hits from the pump. Start-up is where most wear occurs, so this really helps.

Not all synthetics are alike. A main difference is in ash content. Castrol is fairly high, while Mobil1 & Amsoil are almost zero. High ash content doesn't wreck the properties, but it does mean that you should change it more often.

Conventional oil gets to a 15w 30 or 10w 40 rating by the use of additives. No problem if you change it every 3000 miles. But if you don't, those additives wear out and it's SLUDGE city. Plus, conventional, additive based oil is murder on the common shaft in your turbo. If you turn off the car before an adequate spin-down (like 30 seconds minimum after a nice hard drive), the oil left on the shaft will cook into crispy crud. Synthetic oil should get a spin-down, too, but it's more forgiving.
Lastly, if you live in a cold climate, there's nothing like hearing the motor spin fast on a -20 F morning and start right up. 10w 40 and you're walking.

I even get an extra 1.5 mpg from putting synthetic gear oil in the tranny. Smoother shifts, too.

If your motor's not burning oil now - regardless of milage - it won't with synthetic. If it IS burning it now, it will really burn it with synthetic. In that case, stick with 15w 30 and /or STP
DON'T TAKE MY WORD FOR THIS! Type in "synthetic oil" on google.com and study for yourself.

bvtran · Jun 21st, 2003, 02:09 PM

If your engine and its related components didn't have a lot of rush on them. I wouldn't worry. Seems to me your car is still new, so go for it.

I know when I first brought my '94 Nissan Maxima, it got 200K miles on it. The engine looks great, so I flushed it and put in Amsoil Original Synthetic 5W-30 and Amsoil oil filter into it and I got NO problems so far. No leaks or whatsoever.

I've personally like Amsoil a lot, their performances are outstanding. However, I wouldn't do what they warranted. I would still drain my car every 6,000 miles instead of 25,000K like they said.

I wanted to try their ATF too. When I do, I'll get back to you guys on that.

sentrapower93 · Jun 21st, 2003, 04:16 PM

Mobil 1 10w30 and a nissan oil filter works for me. I've owned my car since it was brand spanking new. I now have 116k miles, still get 35 mpg on the high way and my 1.6 still runs strong. Mobil 1 ownz me...