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I have 2,600 miles on the motor and I switched Amsoil SERIES 2000 - SAE 0W-30 Synthetic Motor Oil.
My question is, did I change to synthetic to soon? I've noticed a big increase in performance from 40 mi. to 2,600 miles, I hope this won't mess up my break-in.

Tinman
 

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Captain Thread Killer returns
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Tinman said:
I have 2,600 miles on the motor and I switched Amsoil SERIES 2000 - SAE 0W-30 Synthetic Motor Oil.
My question is, did I change to synthetic to soon? I've noticed a big increase in performance from 40 mi. to 2,600 miles, I hope this won't mess up my break-in.

Tinman
I dont see how it would hurt it. I switched to Mobil 1 at 1500 miles. I know several others who have switched early.
 

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I was worried...

Dbluegoat said:
I dont see how it would hurt it. I switched to Mobil 1 at 1500 miles. I know several others who have switched early.
Thanks Dbluegoat, I wasn't sure if it would more or less prevent/slooowwww the motor break-in. I don't know why that thought came a day later... heh
 

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No I dont' think so, alot of cars come with synthetic oil from the factory.

AMSoil is a great oil, that only redline and Mobil 1 can compete with.

The only thing i'm not too hot on is 0w-30.

I like Mobil 1 0w-40 synthetic.
 

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Factory fill here is 10W-30, I had that for 10,000km before switching to a thicker grade. Since these things love to rev, I wouldnt use anything thinner than a 40 grade oil.
 

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I haven't' looked a oil grades since I worked a J-lube @ 15 years ago. Could someone explain 0w-30? as I understood it the viscosity dropped as the oil heated IE: 5w-30 started at 30 and dropped to 5 as the engine reached temp. This was supposed to yield less resistance on the rotating engine and better gas mileage. What is the deal w/ 0w? I was taught that the tolerances and craftsmanship of the engines today (1989 but we can assume quality has only improved) were extremely high. Because of this it allowed us to run lower viscosity oils.

Which also leads me to think that if your logic is "Since these things love to rev, I wouldn't use anything thinner than a 40 grade oil." one of us does not understand the viscosity numbers. It could easily be me. Can I assume you are using a single viscosity oil? 40w is thick stuff and stays that way as it heats. This would put a higher load on your engine. In the winter months, if you have them, the initial start viscosity would be even higher and the oil would be slower to reach critical parts on startup. This leads to engine wear. We only used a heaver weight oil in high compression engines as the HW oils have less tenancy to allow blow-by at the rings. With these LS1's the precision of assembly and relativity low compression I think 40w single viscosity may not be not the right oil.


I'm still not keen on the 0w thing.
 

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Actually it is just the opposite. A 10W-30 oil starts out at the consitancy of 10 weight oil cold and thins to the consistancy of what a 30weight oil is when hot. A 30 weight oil is thinner when hot then a 10 weight oil is when cold. Did I confuse anyone? With the improved tollerances of these motors, I would not recommend thicker oil unless you have over 100,00 miles on your motor. Just my opionion.
 

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Ok I can buy that. It is simmilar to what i believed but I was a little off in my understanding. It kind of puts a good argument aginst using single viscosity oils..

So what is 0w? how low a viscosity are we going to see in 15 years? -3w?
 

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Viscosity

What I learned long ago about the viscosity of oils and multi-viscosity (and maybe it was oversimplified for my intellect... :rolleyes: ) was that the first number represents it's pumping viscosity. Therefore 10W-30 pumps like 10 weight oil at normal temperatures. The second number refers to it's impingibility weight equivalence(it's resistance to being squeezed out from between opposing pieces under pressure) meaning like a single viscosity 30 weight oil.

Many moons ago we had single weight oil, say SAE30HD. The viscosity of the older oils was not very temperature stabilized. If you ever tried to turn over an engine with the crankcase full of SAE30HD in a New England winter you know what I mean. The stuff was like fudge under 20*, and a lot of folks snapped oil pump driveshafts in Chevrolet small blocks of the day. The HD OP shaft was born as a result for us hammerheads that ran SAE30HD year round. The stuff pumped like roughly 20W over 90*. Hence the prolonged warm up periods of the day. It took a while for the stuff to get to the top end of the engine when it was cold, and it's persistence similarly sucked, (it's tendency to cling to parts and retain an oil film between times the engine was run). Cold starts were noisy and wore engines quickly.

The modern oils and synthetics were an absolute blessing when they came along. Their thinner but more stable pumping viscosity, higher resistance to being squeezed out from between parts, and persistence in filming protections allowed the precision engines are built with today, making more bang for the buck and service lives of over 150,000 miles common. Even 25 years ago, an engine that didn't get to sorely needing a rebuild by 80,000 miles was rare.

It wasn't too long ago that Hot Rodders had to run two different weights for our climate. I still do today in the engine in the S-10. 10W40 for the winter, and 20W50 for the summer. Folks used oil additives to increase and stabilize viscosity, impingability, and persistence (like STP or Wynn's friction proofing) that they couldn't get out of the oil can. Wynn's sponsored 'Big Daddy' Don Garlits... :)

The synthetics of today are more viscosity stabilized for a broader temperature range. If it says 5W30 on the can, it's pumpabilty is like 5W oil nearly regardless of temperature (except in extremes), it's impingability is reliably like 30 weight across the same temperature range, and it sticks like glue making cold starts less an issue. The newest 0W first number oils refer to it's pumping weight being similar to water and it's resistance to flow nearly non-existent.

There are other important numbers to be sure. One of the other jobs of oil is to strip heat from remote parts not accessible to water cooling like valve stems and springs, the underside of pistons, distributor shafts and gears, etc., but that'll be another tome sometime.... :)

If anyone has more, better, or correction facts, please feel free to jump in here. Knowledge is power, but only when it is correct and detailed... :D
 

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Thanks for the long and great post.

So a 0w-40 or 0w-50 would be a holy grail according to that post. pumps like water , sticks like honey, no blow-by?
 

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One of the other reasons manufacturers are recommending these oils is for mileage. The motor will handle it and the lower number gives them a little bit more mileage. In the days of CAFE standards, every little bit counts.
 

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0 weight oils

sxty8goats said:
Thanks for the long and great post.

So a 0w-40 or 0w-50 would be a holy grail according to that post. pumps like water, sticks like honey, no blow-by?
Should be. That would be the goal and the grail they've been searching for over the years, but I'll stick with the Mobil 1 5W30 for now and watch the 0 weights usage results carefully. If they follow true to form, GM will never come out with a recommendation to move off their original say, no matter the benefit. That decision will be left up to us, and we will be left holding the bag if it's wrong.
 

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Reason why Holden specified a low visco oil was due to fuel economy/emissions, less resistance so the motor turns over easier.

I spend alot of time going near redline, so last thing I want is metal touching metal at over 5000rpm, also wanted an oil which flowed quickly at startup.

Again it depends how you drive your car. Before I was pretty sedate, now that the car drives how it should, torque and power delivery is brutal, I find that I approach redline alot.

Still get piston slap on cold startup but once warmed up, it disappears and is replaced by what sounds like a ticking lifter, I change oil every 4500km, no oil consumption, no fuel economy or power issues, just the nature of the beast Im guessing.
 

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Tinman, you will be fine with the Amsoil 0-30 Series 2000. It has one of the highest, high temp/high shear indexes in the industry at 3.4. The worry that the oil will thin down too much and cause premature bearing wear or metal to metal contact is addressed in this HTHS index. To compare, M1 and RP 5w30 have 2.9 indices. Another important factor is the viscosity index. Amsoil's 0-30W is tremendous at 195 (M1-162, RP-161). My recommendation would be to run this oil at least 7k, but to change out your oil filter when you hit 3k. LS1's continue their break-in process until somewhere in the 6k range and then the wear metals drop drastically. You chose a great oil and nothing compares from a wear index perspective except other Amsoil oils. Most of my LS1/6 customers choose the Amsoil 5W-30 or 10W-30 because the specs are very comparable and it retails for $2.50 less a quart. I have summarized some baseline tests of Amsoil versus M1 and RP on my web at
 

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Copy and pasted from a guy who knows a lot about oil.


I read that part too, I didn't realize that is what you're referring to. There is a lot of misinformation in that thread, but I didn't have time to register on the board and correct it. 0w30 doesn't mean the oil is at any time a 0 weight oil, since there is no such thing anyways. The first number simply is an arbitrary number given to an oil, based on it's cold cranking performance. This chart illustrates the qualifications needed for an oil to be a 0w, 5w, 10w, etc:

http://www.machinerylubrication.com/Backup/200005/read_oil_can_tab2.gif

The second number does refer to a viscosity, it's the viscosity of the oil at 100c, and it allow for a certain range, so not all 5w30s are created equal, one could be 9.4 cst at 100c, and be almost a 5w20, while another 5w30 could be 12.3 cst at 100c and be almost a 5w40. That's why it pays to look closer at the technical specs on an oil before deciding on it. The LS1 and LT1 both tend to prefer a thicker 30wt oil to a thin 40wt oil for example, which is why I do not like Mobil 1 5w30, it's on the thin end of the 30wt scale, at only 10.0 cst at 100c. The oil I use, Castrol 0w30 (german version) is 12.2 cst, and after my last 6200 mile interval it thickened up to 12.9 cst, making it a thin 40wt oil. My wear numbers were extremely low, much lower than LT1 oil analysis results I've seen using Mobil 1 5w30.
 

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Another bit of info from Patman from LS2.com and LS1Tech.com


If you don't mind, send the guys over to www.bobistheoilguy.com, or more specifically, the message board at http://theoildrop.server101.com/cgi/ultimatebb.cgi

If they are interested in oil, that is the best place for info! I'm not just saying it because I'm one of the admins on there either. It truly is the best resource for the most up to date info on oils, and tons of people post their used oil analysis reports too, so you can compare how different oils do in different cars.
 
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