10w60 is just right for LS1 engine?
- Thread starter Trex101
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I'd ask him which delivers more oil. 5gpm @ 90 psi or 5gpm @ 40 psi and see what he says.
Arent those odd ball weight oils (15w-50, 20w-50, 25w-50, 10w-60) for extreme competition motors? (Not your everyday "street performance motor" with high flow exhaust and K&N filter.)
IMO of course...however manufacture web sites state the same for such weights.
IMO of course...however manufacture web sites state the same for such weights.
The Impala SS uses the LT1 engine. BIG difference!
I would think that for most street and track use 5W40 would be the best over all comprimise with a 5W30 winning under some counditions and say a 15W50 winning under some.10W60 is not going to hurt the engine much if any it just wont help it much either. Until you get a thick oil up to operateing temp. it is a liability. Nothing worse then makeing short trips on a cold engine with say 20W50 in the sump. The wear will actualy increase.
Patman
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Actually, the LT1 and LS1 both have similar tastes in terms of viscosity, they both like an oil that is in the range of around 12 to 14 cst at 100c. If you go lower than this and you drive hard and/or see high oil temps a lot, you'll most likely see higher engine wear in your oil analysis.
Here's a UOA of a 10W-60, $60/qt Shell Helix Ultra Racing oil to be exact. Sheered down to a SAE 40 in 1400 miles of street driving. I willing to bet most of these supposed "ultra thick oils" are nothing of the sort. Their HTHS may not be proportionally higher (temporary sheer), and they sheer out to a Xw40 in short order (permanent sheer).
There are substantial differences in the lubrication systems between the LT1(Gen II) and the LS1(Gen III). Properly blueprinted, the Gen I&IIs prefer something around 12-14 cSt. Gen IIIs prefer something around 10-12 cSt, assuming in both cases that you keep the oil temperatures in check.
Yes, I'm aware of that...and would argue that the LT1 is actually harder on the oil because of its higher ring and cylinder temps.
But I don't think this qualifies as a "BIG" difference. The LS1 and LT1 are both large displacement pushrod V8s. Now if you compare the LS1 and the Northstar, there's a "BIG" difference.
Experience counts, but you need to qualify it.
There were oil pump modifications, bearing changes, etc., to the marine engines he discussed. Also, marine engines are run at or close to maximum output for extended periods. The wave action and bumping around can create the conditions for the oil to be whipped up by the crankshaft. Thicker oil may mitigate these issues for that application.
Few cars ever are used in this manner. Many never get oil very hot either. Personally, I would worry about oil pumps driven off geared extentions to distributors or camshafts, like older American V-8s. The gears or pumps may not last under the stress of high viscosity oils.
Also, LS1s in Australia may be used in areas where there are no speed limits while at the same time being very hot (40C).
In Singapore, your manufacturer oil viscosity recommendations aren't swayed by government testing rules as they in the US (only the viscosity used in the certification testing is allowed as "recommended"). I would stick to that.
There were oil pump modifications, bearing changes, etc., to the marine engines he discussed. Also, marine engines are run at or close to maximum output for extended periods. The wave action and bumping around can create the conditions for the oil to be whipped up by the crankshaft. Thicker oil may mitigate these issues for that application.
Few cars ever are used in this manner. Many never get oil very hot either. Personally, I would worry about oil pumps driven off geared extentions to distributors or camshafts, like older American V-8s. The gears or pumps may not last under the stress of high viscosity oils.
Also, LS1s in Australia may be used in areas where there are no speed limits while at the same time being very hot (40C).
In Singapore, your manufacturer oil viscosity recommendations aren't swayed by government testing rules as they in the US (only the viscosity used in the certification testing is allowed as "recommended"). I would stick to that.
10W-60 oil may not kill your engine immediately, but it will not help it live a long life. GM specifies a 5W-30 oil, and begrudginly accepts 0W-30 and 10W-30 oils.
I strongly suspect that it would be basically impossible to drive on public hiways in a manner that would require that 60W end of the fully warm oil. It is hard enough on a race track to get the oil up into the 265dF range with 5W-30, from 265-280dF 10W-40 is acceptable, from 280-310dF 15W-50 is marginally acceptable, and for 310-340dF is where a 60W oil will be at the correct viscosity for your engine. This is some 100dF HOTTER than your engine was designed to run. Are you seeing 300dF on the DIC?
If you are seeing oil temperatures of 310dF then you will be a lot better off with a bigger oil cooler than a thicker oil.
I strongly suspect that it would be basically impossible to drive on public hiways in a manner that would require that 60W end of the fully warm oil. It is hard enough on a race track to get the oil up into the 265dF range with 5W-30, from 265-280dF 10W-40 is acceptable, from 280-310dF 15W-50 is marginally acceptable, and for 310-340dF is where a 60W oil will be at the correct viscosity for your engine. This is some 100dF HOTTER than your engine was designed to run. Are you seeing 300dF on the DIC?
If you are seeing oil temperatures of 310dF then you will be a lot better off with a bigger oil cooler than a thicker oil.
A friend of mine has a 96 Impala SS (LS-1 engine). He and the people on his Impala forums swear by the GC 0w-30.
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