oil weight
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oil weight My trans am is only a summer car here in michigan. What's wrong with using a heaver weight than 10w 30. Say 20w 50 for added protection in the hot months ? I have 2000 TA with only 8300 miles that I just bought, so this is new for me. Thanks George
Launching!
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From: SC
Well, other than the manual explicitly stating not to use 20W-50....
I like Rotella T6 5W-40 and Delo LE 5W-40 synthetics. $20 a gallon and I run T6 in all the cars you see in my sig.... OK, WalMart was out of the T6 in the gallon last time so the '02 has a gallon of Delo and a quart and a half of T6.
I like Rotella T6 5W-40 and Delo LE 5W-40 synthetics. $20 a gallon and I run T6 in all the cars you see in my sig.... OK, WalMart was out of the T6 in the gallon last time so the '02 has a gallon of Delo and a quart and a half of T6.
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From: Schiller Park, ILL Member: #317
I don't know why anyone would want to use 20w50 in a stock LS1 engine, especially a fresh/tight one with only 8300 miles. The factory tolerences are not designed for such a thick oil.
LS1s seem to show best wear results with oils that are on the thick side of a 30 weight or the thin side of a 40 weight.
LS1s seem to show best wear results with oils that are on the thick side of a 30 weight or the thin side of a 40 weight.
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Thanks, the manual does say 10w 30 or 5w 30. The last post makes a lot of sense that I didn't know about the ls1 and oil weight. I was thinking heavier oil more protection. I have Buell cycle that calls for straight 50 weight so that what go me thinking. What oil weight are you saying when you say thick side of 30 thin side of 40. Are you saying something in the middle of the two. Sorry I don't understand ?
Last edited by sgtrgpfdps; Apr 10, 2013 at 07:29 AM.
Launching!
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From: SC
What I like about the T6 is that it has about 1200ppm of zinc which is good for all your sliding or pivot points (valvetrain) plus it helps ring seal. I know they took it out to help preserve catalytics but what's worse: burning a quart of 800ppm oil every 3000 miles or burning a half quart of 1200ppm oil every 3000 miles? Don't know....
Anyway, a 40 weight will give you some extra shear stability and the T6 or Delo LE 5W-40 will have good cold flow AND hot protection. The oil spends most of its time on the hot side anyway.
FWIW, I was running Summit Racing 10W-40 conventional with 1800ppm zinc in my 400 SBC from the first oil change and the oil analyses I had done at 2500/4500/6500 miles were showing less wear then some fully broken in LS engines. Plus I was driving the car in all temps so even at below freezing I didn't seem to see a whole lot of impact from cold starts on a 10 weight. I have since switched it over as mentioned earlier though.
Anyway, a 40 weight will give you some extra shear stability and the T6 or Delo LE 5W-40 will have good cold flow AND hot protection. The oil spends most of its time on the hot side anyway.
FWIW, I was running Summit Racing 10W-40 conventional with 1800ppm zinc in my 400 SBC from the first oil change and the oil analyses I had done at 2500/4500/6500 miles were showing less wear then some fully broken in LS engines. Plus I was driving the car in all temps so even at below freezing I didn't seem to see a whole lot of impact from cold starts on a 10 weight. I have since switched it over as mentioned earlier though.
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Thanks, the manual does say 10w 30 or 5w 30. The last post makes a lot of sense that I didn't know about the ls1 and oil weight. I was thinking heavier oil more protection. I have Buell cycle that calls for straight 50 weight so that what go me thinking. What oil weight are you saying when you say thick side of 30 thin side of 40. Are you saying something in the middle of the two. Sorry I don't understand ?
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TECH Apprentice
Joined: Apr 2011
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From: Bahrain
I don't know why anyone would want to use 20w50 in a stock LS1 engine, especially a fresh/tight one with only 8300 miles. The factory tolerences are not designed for such a thick oil.
LS1s seem to show best wear results with oils that are on the thick side of a 30 weight or the thin side of a 40 weight.
LS1s seem to show best wear results with oils that are on the thick side of a 30 weight or the thin side of a 40 weight.
In Fact, i've never faced any engine problems since i got the car.
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From: Schiller Park, ILL Member: #317
What I like about the T6 is that it has about 1200ppm of zinc which is good for all your sliding or pivot points (valvetrain) plus it helps ring seal. I know they took it out to help preserve catalytics but what's worse: burning a quart of 800ppm oil every 3000 miles or burning a half quart of 1200ppm oil every 3000 miles? Don't know....
Flat tappet is different. The friction seen in that application is much greater, and ZDDP reductions in modern GF-3/GF-4 or higher oils can certainly be a problem there.
That link above to bobistheoilguy.com is a good read for anyone that wants to better understand this topic in general.
Last edited by RPM WS6; Apr 10, 2013 at 04:52 PM.
The factory tolerences are not designed for such a thick oil.
people always say newer engines have tighter tolerances, that may be true provided you know the definition of the word. however everyone misuses that phrase and interprets it to mean tighter or less bearing "clearances" which results in needing to use a thinner oil. that is not true. crankshaft and rod bearing clearances are based on their diameter and have not changed. And as those clearances open up from mileage and wear, you will need to use a higher viscosity oil to maintain good oil pressure and protection.
http://www.widman.biz/English/Calculators/Graph.html
the viscosity of the oil is chosen based on operating temperature.
If you run hotter oil temps then you need a higher viscosity oil is you want to maintain protection.
a 5w30 oil at 0° F has the same viscosity/pumpability as a 20w50 at 32° F.
no one ever squawks about starting their car at 0° with 5w30 and everything ever printed shows 5w30 oil is good to below 0° F. so what does that tell you?
a 20w50 oil is fine to use in anything as long as the temps stay above freezing, because it's a multigrade oil. If you were to use a straight weight SAE 40 or SAE 50 then that's different, and I remember seeing bottles of castrol marked with do not use below 40°F for sae 40 and not below 60°F for sae 50.
Joined: Nov 2001
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From: Schiller Park, ILL Member: #317
it's not tolerances, it's clearances. tolerance and clearance are two completely different things.
people always say newer engines have tighter tolerances, that may be true provided you know the definition of the word. however everyone misuses that phrase and interprets it to mean tighter or less bearing "clearances" which results in needing to use a thinner oil. that is not true. crankshaft and rod bearing clearances are based on their diameter and have not changed. And as those clearances open up from mileage and wear, you will need to use a higher viscosity oil to maintain good oil pressure and protection.
http://www.widman.biz/English/Calculators/Graph.html
the viscosity of the oil is chosen based on operating temperature.
If you run hotter oil temps then you need a higher viscosity oil is you want to maintain protection.
a 5w30 oil at 0° F has the same viscosity/pumpability as a 20w50 at 32° F.
no one ever squawks about starting their car at 0° with 5w30 and everything ever printed shows 5w30 oil is good to below 0° F. so what does that tell you?
a 20w50 oil is fine to use in anything as long as the temps stay above freezing, because it's a multigrade oil. If you were to use a straight weight SAE 40 or SAE 50 then that's different, and I remember seeing bottles of castrol marked with do not use below 40°F for sae 40 and not below 60°F for sae 50.
people always say newer engines have tighter tolerances, that may be true provided you know the definition of the word. however everyone misuses that phrase and interprets it to mean tighter or less bearing "clearances" which results in needing to use a thinner oil. that is not true. crankshaft and rod bearing clearances are based on their diameter and have not changed. And as those clearances open up from mileage and wear, you will need to use a higher viscosity oil to maintain good oil pressure and protection.
http://www.widman.biz/English/Calculators/Graph.html
the viscosity of the oil is chosen based on operating temperature.
If you run hotter oil temps then you need a higher viscosity oil is you want to maintain protection.
a 5w30 oil at 0° F has the same viscosity/pumpability as a 20w50 at 32° F.
no one ever squawks about starting their car at 0° with 5w30 and everything ever printed shows 5w30 oil is good to below 0° F. so what does that tell you?
a 20w50 oil is fine to use in anything as long as the temps stay above freezing, because it's a multigrade oil. If you were to use a straight weight SAE 40 or SAE 50 then that's different, and I remember seeing bottles of castrol marked with do not use below 40°F for sae 40 and not below 60°F for sae 50.
But to your point, I should have just used the word "clearances" to avoid any confusion or misunderstanding.
IMO, 20w50 is not the right oil for what has so far been stated in this thread of this engine and its usage.
TECH Apprentice
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From: Bahrain
There is one more thing i forgot to add ... i'm not using 20w 50 because i lack the knowledge which tbh i do lack some..
but every bird,camaro, corvette i know .. uses that oil weight..
the thing is.. it's screamingly hot here reaching 40° "Celsius" at times.
running oil that's thinner will just screw me over, even at times in the summer our engines may over heat when used aggressively.
and that's basically why we all go with 20w 50 out here, just safer.
but every bird,camaro, corvette i know .. uses that oil weight..
the thing is.. it's screamingly hot here reaching 40° "Celsius" at times.
running oil that's thinner will just screw me over, even at times in the summer our engines may over heat when used aggressively.
and that's basically why we all go with 20w 50 out here, just safer.
Joined: Nov 2001
Posts: 34,632
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From: Schiller Park, ILL Member: #317
There is one more thing i forgot to add ... i'm not using 20w 50 because i lack the knowledge which tbh i do lack some..
but every bird,camaro, corvette i know .. uses that oil weight..
the thing is.. it's screamingly hot here reaching 40° "Celsius" at times.
running oil that's thinner will just screw me over, even at times in the summer our engines may over heat when used aggressively.
and that's basically why we all go with 20w 50 out here, just safer.
but every bird,camaro, corvette i know .. uses that oil weight..
the thing is.. it's screamingly hot here reaching 40° "Celsius" at times.
running oil that's thinner will just screw me over, even at times in the summer our engines may over heat when used aggressively.
and that's basically why we all go with 20w 50 out here, just safer.
This is the same weight I use. M1 tends to run on the "thin" side of their ratings, so their w40 is similar to some of the "thicker" w30s, and oils in that range usually show excellent wear results for stock LS1s.
I ran 20w50 in my 427ci for 173,000 miles till a rod broke........pretty kick ***.
20w50 is perfectly fine for any LSx engine. Only time you need to use anything differently is when a builder puts together a specific engine with specific tolerances and the builder says to use a certain type and weight of oil.
.
20w50 is perfectly fine for any LSx engine. Only time you need to use anything differently is when a builder puts together a specific engine with specific tolerances and the builder says to use a certain type and weight of oil.
.
12 Second Club
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From: Bucks County, Pa.
Perhaps your extreme climate dictates some different oil weights for best results. Here in the midwestern/great lakes region of the US (where the OP resides), 20w50 would not be required for average street use of a stock LS1 engine...even in the summer months.
This is the same weight I use. M1 tends to run on the "thin" side of their ratings, so their w40 is similar to some of the "thicker" w30s, and oils in that range usually show excellent wear results for stock LS1s.
This is the same weight I use. M1 tends to run on the "thin" side of their ratings, so their w40 is similar to some of the "thicker" w30s, and oils in that range usually show excellent wear results for stock LS1s.
The M1 0W-40/Red Line 0W-40/Motul Trophy 0W-40/etc. are the THICKEST oils I would use in a stock clearance LSx, save for our middle eastern desert dwelling friends, and maybe southern Tejas/Arizona in the middle of the summer.
The advantage of the Mobil 1 product is it's price vs. specs/add pack contents (it is practically a 'boutique' oil like the mentioned Red Line/Motul/Torco/etc.), AND it is available right on the shelf (in lower cost, 5 qt. jugs no less) at your local China-Mart.
12 Second Club
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From: Bucks County, Pa.
This may be true for their regular line Mobil 1 oils, but it is DEFINITELY NOT true for their 0W-40, or racing line.
Their 0W-40 meets or beats ALL of the most stringent Euro (Merc/Porsche/Audi) specs, has a very good viscosity index (only beat by Red Line in this weight), uses better base stocks than their regular M1 line, and has a very high ZDDP/moly/calcium/etc. content in it's add pack.
Their 0W-40 meets or beats ALL of the most stringent Euro (Merc/Porsche/Audi) specs, has a very good viscosity index (only beat by Red Line in this weight), uses better base stocks than their regular M1 line, and has a very high ZDDP/moly/calcium/etc. content in it's add pack.