I want to switch to synthetic and want to know how many miles I should drive on basic dino oil first for a good breakin.

'04 G35 Sedan, Black, Sport sus., all opt. but nav

'92 Vette Vert, 6-Spd, too much to list

'95 ZJ Laredo, 5.2 V8, more

 

I've read a ton of opinions on this. As far as I can tell, you wouldn't get anyone to disagree with doing it at the 2nd oil change. That's when I'm going to do it. My personal feeling is with this engine you can do it anytime, but there's no harm in waiting just a bit.

2003.5S AT / DP / Graphite / Premium / Aero / Sport / Splash

 

Well, if the second oil change is around 6000 miles, then I won't disagree. My second oil change was at 3000 miles. I would wait at least 6K for Mobil 1. Otherwise, go with Castrol GTX until then.

'03.5 Brilliant Silver Sedan
Premium, Aero Kit/Package, Sport, Winter
Stillen Air Box, Z pipe, Clear Corners, Alum Pedals
Polk Tweeters

 

I'm changing my oil the first time at 1000-1500. New motors have metal burrs inside that wear off the first thousand miles or so. Most get caught in the filter, most. On the flip side, my vette MUST use Mobil One and it comes with it from the dealer. I believe they run the motors for an hour or two at the factory and then put in the synthetic. Also if you have a vette motor rebuilt, the standard practice of all the vette motor tuners like Ligenfelter, Rippie, etc. is a 150 mile breakin then to synthetic. The vette motors, especially mine, were designed to run hot. Mine has reverse coolant flow where the coolant goes through the heads first and then the block cooling off the heads and manifold making more power. The negative is that the motor runs much hotter, mine seeing 220 degrees on hot days in stop and go, 198 cruising so a normal oil will break down and gunk up in no time. But since it has been on synthetic its whole life, it runs as strong or stronger now than it did 10 years ago and you can eat off the valves with 85K miles. Clean and basically looks new inside. Good stuff. Vettes with owners that don't care and put cheap stuff in rarely make it past 100K without a rebuild though the ones that do regularly go well over 200K with no problems. I'm sure they will go further but there aren't many owners who drive there vettes that much to find out. Anyway, I want to switch as soon as breakin is complete. 6000 seems very excessive. I'm changing the oil at 1.5K and probalby will go to Mobile One unless someone else has any feedback.

'04 G35 Sedan, Black, Sport sus., all opt. but nav

'92 Vette Vert, 6-Spd, too much to list

'95 ZJ Laredo, 5.2 V8, more

 

Well, this has been rehashed over and over. If you talk to Mobil, they say to wait at least 6k. If you read about our engine, you will see it takes longer to break in than many other engines. If you think logically, you should let your engine break in first before switching to synthetic. If you know about engines, you know that you should put about 6k on your engine before blowing it (due to engine break in and valve seating). If you knew the answer to your question before you asked it, why ask?

'03.5 Brilliant Silver Sedan
Premium, Aero Kit/Package, Sport, Winter
Stillen Air Box, Z pipe, Clear Corners, Alum Pedals
Polk Tweeters

 

Also, vette tolerances are alot tighter than ours. That is a high performance engine, ours is not, despite what some people think. Break-in is not as much of an issue with your vette vs. our g35.

'03.5 Brilliant Silver Sedan
Premium, Aero Kit/Package, Sport, Winter
Stillen Air Box, Z pipe, Clear Corners, Alum Pedals
Polk Tweeters

 

i switched @ 3100 miles. works fine.

 

Okay, so why exactly does it take longer to break-in I have always used 1000 miles as the break in, but was wondering why the recommended on this engine is 1200. Someone here actually was told to keep it below 60 before 3k by someone, geez!

Brilliant Silver/Graphite '04 Sedan

 

Actually, if you look on Mobil's website, they'll say it's the factory fill on many cars (such as the Corvette) and you can switch to it right away. To be fair, it was probably a marketting person that wrote that.

I switched at the 7500mi change, mainly because my dealer gave me a free first oil change.

2003.5 G35 Sedan Desert Platinum/Graphite Premium/Sport/Aero/Nav/Winter

 

NEVER! Switch to Havoline synthetic. Just as good but cheaper. And you'll be fine doing it on the first oil change. In fact, like the Mobil 1 website says, you can do it any time, even at 0 miles.

Dave

 

I know many people with old old nissans including: pathfinder, celica, sentra, maxima that are above 150k in miles. a friend of mine has an older altima with over 200k. all used regular oil. You do not need synthetic oil. But most of you out there being G junkies will find anyway you can to spend extra money.

 

I'll only go to a true synthetic like Mobil One or Amsoil. The others, castrol, Quakerstate, Havoline, all are not completely synthetic, only partially synthetic and as a result cheaper.

The benefit of full synthetic oil is that the oil molecules are all of a uniform size. Dino oil has molecules of all sizes. Partial synthetic oils have less of these but still have some as they are part dino. Smaller molecules burn up at lower temps and leave residue behind. This residue can build up in the gaps where gaskets are present. If you switch to synthetic after dino, you can sometimes break up these areas where the dino oil was left filling gaps and cause oil leaks. If you go to dino oil too soon, you won't break in the motor properly as the syntetic stuff is so slick, it prevents wear.

I plan on going many more miles than the typical G driver or I would just use dino oil. I won't be suprised if I hit well over 200K as this is a work car and I will be going close to 1K a week.

I'll probably swap at my first change, which I'd like to do around 1,500 miles.

I would be surprised if the vette was made to higher tolerances than the G motor. It is larger and has a high compression and high operating temp, but it isn't as refined or smooth. The G motor puts out more power per cubic inch than the vette.

Thanks for the replies though.

'04 G35 Sedan, Black, Sport sus., all opt. but nav

'92 Vette Vert, 6-Spd, too much to list

'95 ZJ Laredo, 5.2 V8, more