LS1 engine, 5w or 10w-30 oil question

[fnbrowning]

Let me set up a basis for this question.
I have a 2002 LS1 Trans Am. It has ~14,000 miles.
I run Redline exclusively in the T/A.

The GM owners manual strongly recommends using 5w30 oil and allows the use of 10w30 oil above 0 degrees F.

I was running 5w30 for the first few changes until I read a couple of years ago in the various LS1 forums that people were migrating to a 10w30 oil to quiet their engines. The LS1 is an all-aluminum V8, and because of the hypereutectic piston design, there has been ongoing complaints of the noise from piston slap. The valve train isn’t all that quiet either.

A number of people experimented with 10w30 oils and felt that their LS1 engines ran quieter.
ALSO, it was being said that GM really preferred 5w30 oils only because of CAFÉ mileage, and that for high speed driving and WOT runs, the 10w30 oils gave a better margin of protection.

Okay, so reading that, at the time, I switched to the 10w30 Redline as a precaution.

So now it’s 2005, and I’m reading information on oils where it appears that thinner oils are better for most engines as it increases oil flow and lubrication across bearings and reduces startup wear.

So this is my question:

On the aluminum LS1, or other modern American V-8 designs, does the use of 10w30 oil instead of 5w30 0w30 cause accelerated start-up wear and less flow & cooling?
Or, {since I'm using top tier brands line Redline} - Are the lubrication properties of top synthetics superior enough that the wear numbers between 5w & 10w are not significant?

Is the 10w30 a better or worse oil for a car that sees those WOT excursions, but is NOT a daily driver and is NOT operated at < 20 degrees F.

Thanks for reading my long winded question!!

 

[sgtgeek]

See the search button up there...type in LS1...man you'll get a bunch of discussions.....I have a modified 04 GTO LS1..Head/Cam/Intake/Headers etc...400 RWHP....spent a lot of time on the dyno and a lot of time here on BITOG Spoke with a ton of mechanics and engine builders......LS1's like the heavier oils...Mobil 1 5w30 is thin and thins out even more per the used oil analysis...I went with a 10-40 Amsoil and the Goat performed well on the dyno and at the strip........now....I am on a strict 0-30 GC and 0-30 Amsoil diet....top performance and great engine protection.....the LS1 loves this quality 0-30 stuff.......so my choice(s) and the choice of many informed LS1 owners looks like this....
1. GC or Amsoil 0-30
2. Amsoil 10-40
3. Mobil 1 0w40

 

[Dave Hess]

sgtgeek,

Have you considered Mobil 1 Truck and SUV oil or a Mobil 1 - 10w30/15w50 mix ?? In some cities, GC Syntec is impossible to find.

[ March 25, 2005, 10:22 PM: Message edited by: LT4 Vette ]

 

[sgtgeek]

Yeah I did some mixing and we dyno'd the thing with it in there.....and you know dyno's....so many varibales during the runs...heat soak/humidity etc but never really saw any increase in performance.....but I have to say my mixing days are over with the numnbers we are getting with the 0-30's...now I have a Perma Cool oil cooler and dual filter setup....my oil temps never see much past 190 even after hard runs......of course the coolant (liquid) temps stay right at 195.....
I do agree with you on the higher viscosity for the LS1's over the factory CAFE/EPA (driven) recommended 5-30 stuff

I agree the GC is a joke to try and find...that is what led me to the Amsoil 0-30.....**** good stuff with a proven record in these engines.....

 

[SSDude]

Just put some GC in your car and relax.

 

[DJ]

The hot viscosity difference between most 5w30 and 10w30s is marginal at best heck I think the beloved M1 the 10w30 is actually thinner. you have a lot more reading to do before you get a grasp of this stuff. Also I am not saying Redline is not good oil but Redline/Royal Purple and the like have a marketting image of being so exotic and special. The used oil analysis here show that they are often good oils but not to the level worth mailorder and price.

 

[TooSlick]

I sell both the Amsoil 5w30 and 10w30 simply because of customer demand. But in fact I could simply sell nothing but the Series 2000, 0w30 and not even bother with the other grades.

I find NO performance difference between the Amsoil 5w30 and their 10w30. I do find better performance and a small (about 3%) fuel savings with the Amsoil 0w30 over their 5w30 or 10w30 in most applications.

TS

 

[Blue99]

quote:

---

On the aluminum LS1, or other modern American V-8 designs, does the use of 10w30 oil instead of 5w30 0w30 cause accelerated start-up wear and less flow & cooling?

---

No. The SAE designation of xW simply indicates the cold temp viscosity, -35C for 0W, -30C for 5W, -25C for 10W. The majority of API energy conserving 30 weight oils will be in the 10.0 to 10.9 cSt range at 100C (212F) operating temperature.

Many 5w30's and 10w30's have very similar viscosities at common ambient temps from 32F to 70F degrees.

As an example, Redline 5w30 and Mobil 1 10w30 are virtually the same viscosity in the 32F to 70F temperature range for start-ups. At full operating temps, the Mobil 1 10w30 is slightly thinner at 10.0 cSt vs Redine 5w30 at 10.9 cSt.

quote:

---

Are the lubrication properties of top synthetics superior enough that the wear numbers between 5w & 10w are not significant?

---

In general, even conventional oils do not exhibit greater wear numbers directly attributed to a 5W or 10W viscosity rating, unless the oil grade is simply inappropriate for the engine.

The main advantage to using a 5W vs a 10W, at temps over 32F, are small fuel economy gains while driving the vehicle before it reaches full operating temperature.

 

[Mike_dup1]

I also have a 2002 LS1 WS6. I have been using Amsoil ATM 10w30 since my first oil change in Oct 02. Went 1 yr on OEM oil which according to GM inside sources was Mobil 1 evern though it was not publized as being installed at the Factory. They switched over sometime in Sept/Oct 2001.

I only drive my car from May to Oct, change oil every Oct, which has never been more then 7000 miles more or less. Mine does make the cold engine noises as does a friends 2002 Vette and many other LS1 I have observed. Once it warms up, its quite. Mine has only been back to dealer for one minor problem. Had a coolant leak that was only a bad clamp.

As for the cold engine noise, "my gave-a-damm is busted"

 

[sgtgeek]

I haven't seen one either...of course used oil analysis are good for mebbe determining OCI's and such but I wouldn't base my choice of oil for a high performance engine on a used oil analysis from a grocery getter

I base my statement on looking over the shoulder of LS1 teardowns at the shop using the stuff....on numerous conversations with racers and street monster drivers/mechanics...they all swear by Amsoil 0-30.....nuff for me.....The dyno told me what I needed to know.....**** Buster Google Amsoil 0-30 LS1..... http://www.cranecams.com/?show=streetShark
look at the first mods....Amsoil 0-30...
http://www.vincihighperformance.com/fbodyls1ultimate.html
now do you think these guys know what they are doing...I do.....ain't no secret

[ March 26, 2005, 01:48 PM: Message edited by: sgtgeek ]

 

[buster]

Thanks, I wasnt suggesting 0w30 doesn't do well in LS1. I'm sure Redline is very popular as well. Vincihiperformance was a Valvoline user before using Series 2000. That doesn't say much. I'm sure the Amsoil works well.

 

[sgtgeek]

quote:

---

Originally posted by buster:
Thanks, I wasnt suggesting 0w30 doesn't do well in LS1. I'm sure Redline is very popular as well. Vincihiperformance was a Valvoline user before using Series 2000. That doesn't say much. I'm sure the Amsoil works well.

---

I am at mile 500 (that is 500 pretty hard miles)
with GC 0-30.....after a few more runs and a couple of trips to town...I have my Blackstone Lab bottle ready to go....I then want to do the same OCI and UOA with the Amsoil just to see....I'll post both up soon as completed.....I will say...the GC is still green!

 

[buster]

quote:

---

I am at mile 500 (that is 500 pretty hard miles)
with GC 0-30.....after a few more runs and a couple of trips to town...I have my Blackstone Lab bottle ready to go....I then want to do the same OCI and UOA with the Amsoil just to see....I'll post both up soon as completed.....I will say...the GC is still green!

---

Look forward to those comparisons. My friend put Series 2000 in his Vette and claimed his engine temps were lowered by 15 degrees.

BTW, Texas Hill Country is the nicest part of Texas. No offense to Texans, but the rest of the state isn't that scenic. I never quite understood what Bush sees in his Crawford Ranch.

 

[sgtgeek]

I see that also....on the GC that is....Oil pressure is pretty much the same but oil temp maximizes at 190....I'm curious of the Amsoil 0-30...last time I ran it I didn't have an oil temp guage...do now
Yup....I wouldn't live anywhere else....Ranch here on the Guadalupe River......Houston/Dallas/Ft.Worth....another country to us HillBillies

 

[Ryan00TJ]

I run straight Schaeffer 15w40 Blend during summer and a 4qt 10w30 @ 2 1/4 qt 15w40 mix during winter. Both of these combo's have proven great results in used oil analysis. I will be switching to Schaeffer's new PAO 5W-40 and will run it all year.

 

[buster]

quote:

---

that is what led me to the Amsoil 0-30.....**** good stuff with a proven record in these engines.....

---

I've yet to see a used oil analysis of Amsoil 0w30 in a LS1/C5 engine.

 

[Mike_dup1]

quote:

---

I've yet to see a used oil analysis of Amsoil 0w30 in a LS1/C5 engine.

---

used oil analysis are only useful for the specific engine being tested, not for all that are similar or for the oil. You cannot use that info to make any comparisons to other vehicles or oils. No two vehicles will perform the same, just like no two drivers will drive them the same. So seeing a few used oil analysis from a few LS1 engines will tell you absolutely zero about the oil. It will only tell you about these engine being tested. You are talking a few vehicles out of thousands and possibly millions and jumping to a conclusion. No more than you can say we have tested 2 people in town who drink Miller Beer and found they were Aholes , so everyone who drinks Miller Beer in the same town must be also.

I often hear was appears to be conclusions made from a few used oil analysis on a particular oil which are false and misleading conclusions.

Thats my opinion, don't get po'd about it.

 

[sgtgeek]

quote:

---

Originally posted by Mike:

quote:

---

I've yet to see a used oil analysis of Amsoil 0w30 in a LS1/C5 engine.

---

used oil analysis are only useful for the specific engine being tested, not for all that are similar or for the oil. You cannot use that info to make any comparisons to other vehicles or oils. No two vehicles will perform the same, just like no two drivers will drive them the same. So seeing a few used oil analysis from a few LS1 engines will tell you absolutely zero about the oil. It will only tell you about these engine being tested. You are talking a few vehicles out of thousands and possibly millions and jumping to a conclusion. No more than you can say we have tested 2 people in town who drink Miller Beer and found they were Aholes , so everyone who drinks Miller Beer in the same town must be also.

I often hear was appears to be conclusions made from a few used oil analysis on a particular oil which are false and misleading conclusions.

Thats my opinion, don't get po'd about it.

---

AMEN!!!!!
Can I use your Miller Beer anology...that is great man

 

[fnbrowning]

Thanks for all the interesting replies. I have searched the oil drop for tidbits on the LS1 & on Redline oil. I have to say that this server does not have the best search engine, and in regard to "LS1" the returns claimed to contain the word do not always bear it in useful text.

I think Blue99 posted a good reply in plain English:

quote:

---

No. The SAE designation of xW simply indicates the cold temp viscosity, -35C for 0W, -30C for 5W, -25C for 10W. The majority of API energy conserving 30 weight oils will be in the 10.0 to 10.9 cSt range at 100C (212F) operating temperature.

Many 5w30's and 10w30's have very similar viscosities at common ambient temps from 32F to 70F degrees.

As an example, Redline 5w30 and Mobil 1 10w30 are virtually the same viscosity in the 32F to 70F temperature range for start-ups. At full operating temps, the Mobil 1 10w30 is slightly thinner at 10.0 cSt vs Redine 5w30 at 10.9 cSt.

In general, even conventional oils do not exhibit greater wear numbers directly attributed to a 5W or 10W viscosity rating, unless the oil grade is simply inappropriate for the engine.

The main advantage to using a 5W vs a 10W, at temps over 32F, are small fuel economy gains while driving the vehicle before it reaches full operating temperature.

---

For someone like myself, for whom oil and lubrication is not a hobby, we seek the plain answers from those who enjoy sharing their experience.

Another thread in this forum recently had this url: Redline Product Sheet
Of course, they are drumming their product; but I like what they said:

quote:

---

Best all-round, synthetic oil for stock or slightly modified engines in high-performance cars that are street-driven. Best choice to replace a 5w30 or 10w30, petroleum-based or other-brand synthetic oil if maximum durability is preferred.

---

Should Redline's claim be reasonably honest, that would be something I seek to learn from those who have tested the product and would like to comment further.

Thanks