TCL

I'd wait until the first scheduled oil change.

DIGItonium

iTrader: (1)

We're aiming for 3000 miles... it's overkill, but we're not forced to drive this car everyday so it'll be weekend for now.

500 miles... we're changing oil using regular.
Then at or before 3000 miles, we're moving to synthetic.

I'm still deciding on diff and tranny oils.

Todd

Why can't you use synthetic from the begininning?

jreiter

iTrader: (6)

Todd, synthetic oils generally cause much less wear on an engine than organic oils. The first few thousand miles of an engine's life are very important for getting things broken in by causing the correct kind of initial wear on things like cylinder walls. It's good to use organic oil for that break-in period to make sure things actually get that initial wear in them. I'm not sure on the *exact* types of wear you want to get, but you won't get it with synthetic.

VQracer, you might want to reconsider your use of Mobile 1. I don't know if what I heard is true, but there was *lots* of discussion about it on the Audi boards I frequent. Apparently Mobile 1 is no longer going to be full synthetic. I seriously hope that's not right, but you might want to research it and keep and eye out. If it does turn out that Mobile 1 does go that unfortunately route, you may want to start using Redline or Amsoil. Both considered to be some of the best oils you can get, but both can be a bit hard to find and expensive.

LS350Z

I've been hearing this Mobil 1 story for the last 5 years and I highly doubt that will ever happen, although stranger things have happened. The first rumor was in 2000 Mobil 1 would be non-synthetic. Now it just appears to be in some random time frame in the future.

As far as oil choices go, Redline synthetic oil is way over rated, breaking down a good 20% faster then some convential oils. Amsoil (which missed our testing for the first 5 years) is decent but still way over priced and is no better then Valvoline Snythetic or Castrol Sythentic.

I do not work in or around oils but I've got significant reasons to test them yearly, and every year the results are within standard testing deviations. I can not post exact numbers but I can give rough estimates.

Mobil One viscosity and thermal breakdown is nearly 15% better then the next closest brand Valvoline Synthetic. Castrol, Amsoil & Mobil are all close behind and for all realitive purposes are the same. There's a 1% error on the testing but after 9 years of testing I can conclusively say that Valvoline Synthetic is statistically better (notice statistically only ).

The leading convential oil is by far Valvoline.

Penzoil is by far the worst oil tested and has even fell below some no-name brands tested (although it's interesting to find out through testing data only which no-name oils are simply re-packaged brand-name oils).

The reason for this post is before continueing to spread rumors, stop and think about the validity of it. If you heard a rumor on an Audi board, tell it on a Nissan board, next thing you know I'll hear it on one of my Chevy boards.

articfury

LS350Z-

Have you ever included Royal Purple in your tests? Just wondering how it compared to the others mentioned.

JD

AudioPat

Here's an uneducated question...When changing to synthetic, is there anything you need to do to the system, such as flushing it out, before you make the change? I remember a wrench saying something about this when I considered going to synthetics in my bike..

DIGItonium

iTrader: (1)

Sorry...eheh. I don't want to make it sound like the car is 100% mine and that I bought it.

It's my dad getting me the car and it's financed... thank goodness for that option!

Anyhow, I'll be taking over responsibility of the car, maintenance, and payments when I get out of college and get a good job towards my degree.

So in a way, I'm happy I'm not getting a "free ride" like some lucky people. I want to be able to help with the payments. I help my dad back too. With watever I save up, I'm helping him with his 90' 300ZX TT.... security, options.

Basically... this is how we bond, besides getting my (_|_) whooped by him shooting pool. It's a like father like son thing... his old gen Z, and my new gen. Z. Doesn't that sound nice?

BTW... you don't have to be a baller to get this Z... he got it at a bargain price of $6500. Still runs great, and it turns heads!

Flyingscot

I'm sorry to hear that Penzoil was the worst because that's what I have been using in my Nissans for years. What was the issue with Penzoil?

DIGItonium

iTrader: (1)

I don't really know, but my mechanic says it makes the inside of the engine "dirty."

My guess is clumps of stuff builds up.

Flyingscot

Okay thanks for the info. I think he's referring to "sludging". This is not a good thing. Good thing I switched my car to Mobile 1 recently.

jreiter

iTrader: (6)

LS350Z, thanks for the detailed report. I had no idea that the whole Mobile 1 story had been around for so long. I apologize for spreading the rumor. (Just trying to look out for my fellow car enthusiasts.)

LS350Z

It's all good. I understand why you did what you did but that's also why things like this get blown out of proportion. Typically a rumor has 5% truth behind it and in some ways that does scare me but at the same time it's pretty much infathomable to think Mobil one would go non-synthetic. I think, and this is years of thinking, that the whole rumor started back when semi-sythentics came out and Mobil started experimenting with those.

articfury - Royal purple has been tested in the past but hasn't been tested for the last 2 years (no idea why either). It comes out in the major 'average' group of all oils.

AudioPat - That's a great question and honestly there is no correct answer. Some will argue a flush is needed, some will argue otherwise. The fact is there is no hardcore data proving either side. If I have a fresh motor that's never had oil, I start off with sythetics. I've done this on 2 drag motors and my ITB Rabbit motor with great results. If I have a new car motor where the auto manufacture uses conventional oils to start I drain the fluid at 600miles and then switch to sythentics with a final oil change at 2500 miles (if you go the 2500 mile oil change route like I do, otherwise 3000 would be fine). Everyone has their own opinion and everyone has good points to an extent, the best route is to do what makes you feel comfortable.

Flyingscot - the biggest failure of Penziol is it's thermal breakdown point. The viscosity breakdown is still lower then average but the thermal breakdown point is way way lower then average, almost a full 50% lower then the group average. My best guess as to the cause is this is due to the detergents they use in their oil which under high shearing are burnt away from the oil.

djtonium - your mechanic is right about the sludge which is due to the thermal breakdown. Viscosity breakdown will turn oil jet black and will also aid in the 'sludging' but the thermal breakdown is what kills it.

It's very important to note here that none of the oils ever tested should breakdown before a 3000 mile oil change and still offer adequete lubrication under typical driving conditions. It is important to note though that all there's still adequete lubrication there still could be 'sludging' which long term can be very dangerous for a motor. I'm not trying to steer anyone's opinions on oils towards one brand or another, I just want what data I have on them to be out there.

What oil do I choose? I choose Mobil 1 or Valvoline synthentic. If I need a conventional oil for some reason I choose Valvoline. Why do I choose these? I guess the main reason is their superiority but honestly I guess it's one of those 'I've done it my whole life' type things as well.

AudioPat

Kevin,

Thanks for the info...don't think in the early 70's when I last played with cars, technology was what it is today..lots to learn..appreciate the advice

drivebywire

Guys,

Having well said about oil/change interval, what do you suggest about driving habbits? Is it okay to speed (lets say 80+) after 100o miles? or rough driving?

DIGItonium

iTrader: (1)

Thanx for telling me about Valvoline. My mechanic is really my dad's friend who owns a shop, and he's all Valvoline.

I was curious about Valvoline quality... so I feel more confident than ever!

LS350Z

Overall speed is not the concern really, it's engine rpms that hurt you. With the Z being a 6 speed I'm sure 80mph will be aweful low in the rpm band in 6th gear. My gereral appoarch to breaking in a motor (not really oil related either) is to be very gental on the throttle for the first 600 miles for my first oil change. This is the most critical time frame for breaking in seals and piston rings correctly. High engine revving and using 100% power will cause these to break in improperly and often times glaze them over before proper wear patterns occure. After the first oil change (I choose 600 miles), I then slowly begin to work the motor in by slowly taking it to redline for short periods of time and giving it progressively more power. After 2500 miles (3000 would probably be even better but once again I choose 2500miles) I then use the engine however I typically would any other motor.

This is mostely guess work on my part, but I can tell you that I've never had a motor go bad following the above procedure. I have seen motors crap out (typically either burnt up valve guides or broken rings and occasionally spun bearings) when this hasn't been followed, but these are rare cases.

In reality, it typically takes a motor anywhere from 5000 to 10,000 miles to become fully broken in, and this is typically where cars will get their maximum hp.

On my drag motors I've built, we do a 30 minute idle test, pull the heads and adjust the valves (if necessary) and recheck the botton end. After that it's to the drag strip for a season or two of fun sub 10 1/4 miles. Of course on these motors we get 20k miles but they are typically spotless when broken down for rebuild.

Once again these are just my procedures that I've learned and picked up from my years of building motors for my cars and family members. The best bet is to do whatever makes you feel comfortable. There's a lot of people that will have a lot of opinions so listen to them all and formulate your own procedure that makes you feel the safest.