5w20 in LS1
- Thread starter 2Fast4U
- Start date
- Status
Originally Posted By: 2Fast4U
Anybody running 5w20 in an ls1 or ls2? I thought I remembered a while back when someone was claiming that 5w20 caused engine failure in their LS1.
I am on my 1st OCI of 5w20 in my 00 Silverado w/ a 5.3 & 110k+ on it now.(which is an LS1 based engine) No problems, in fact couldn't be happier! Engine runs quiter, revs free'er and got a little better MPG's! It's like a whole different engine, what a difference between 5w20 & 5w30.
Anybody running 5w20 in an ls1 or ls2? I thought I remembered a while back when someone was claiming that 5w20 caused engine failure in their LS1.
I am on my 1st OCI of 5w20 in my 00 Silverado w/ a 5.3 & 110k+ on it now.(which is an LS1 based engine) No problems, in fact couldn't be happier! Engine runs quiter, revs free'er and got a little better MPG's! It's like a whole different engine, what a difference between 5w20 & 5w30.
As far as I know, GM says 5/30 or 10/30 only in their gasoline engines.
You pays your money, you takes your chances.
You pays your money, you takes your chances.
There are these very thin layers of material that make up the crankshaft main bearings. It's always nice to have a sufficient boundary layer of oil between the bearings and the crankshaft's rotating journals. Under periods of high loads, there may not be a sufficient level of film strength to prevent the crankshaft from making contact with the bearing while having a low viscosity oil.
In addition to that, I've been told by an engine builder that the connecting rod bearings (the half that fits in the rod end - not the cap end) are particularly vulnerable to damage when under periods of high loads while under the care of a low viscosity oil.
Originally Posted By: 2Fast4U
I thought I remembered a while back when someone was claiming that 5w20 caused engine failure in their LS1.
I have yet to see reference of any engine failure running 5w-20 where 5w-30 is spec'd. I bet that LS1 wouldn't know the difference.
Joel
I thought I remembered a while back when someone was claiming that 5w20 caused engine failure in their LS1.
I have yet to see reference of any engine failure running 5w-20 where 5w-30 is spec'd. I bet that LS1 wouldn't know the difference.
Joel
How much horse power and torque are we expecting to gain by going from a 10W-30 to a 5W-20?
These may help you understand viscosity, the first one is more complete:
http://ferrarichat.com/forum/faq.php?faq=new_faq_item#faq_haas_articles
http://theoildrop.server101.com/forums/showflat.php?Cat=0&Number=258506&an=0&page=0#Post258506
aehaas
http://ferrarichat.com/forum/faq.php?faq=new_faq_item#faq_haas_articles
http://theoildrop.server101.com/forums/showflat.php?Cat=0&Number=258506&an=0&page=0#Post258506
aehaas
my friend is running Amsoil 0w20 in his trailblazer SS with an LS2..
This is my experience with UOA's on my LS1. I have a 420rwhp@396rwtq H/C 02 LS1 SS. CNC heads, small TR224 cam, all supporting boltons, headers, intake TB, etc....
Rev limiter is 6800rpms and shifts for max power are at 6500rpms.
Out of 8 UOA's 15W-40 Mobil Delvac showed the best wear control compared to Mobil 1 10W-30 and Schaeffer 10W-30. IMO For a hard run performance application thicker is better. The same thinking is used in the marine world of engines. 40W and thicker is standard to keep the engine alive.
Rev limiter is 6800rpms and shifts for max power are at 6500rpms.
Out of 8 UOA's 15W-40 Mobil Delvac showed the best wear control compared to Mobil 1 10W-30 and Schaeffer 10W-30. IMO For a hard run performance application thicker is better. The same thinking is used in the marine world of engines. 40W and thicker is standard to keep the engine alive.
I don't buy the thicker is better mentality. That is old school, so early last century. Or at least the late seventies. This coming from me who is old school. I ran 20w-50 Mobile 1 in my street 327 chevy as late as 1992. So even old dogs can learn new tricks.
Racing and stock vehicles are going to thinner......
Going thicker has it's drawbacks as well. Not as simple as thicker is better.
UOA anyone? Any towing or heavy loads hauled? A good synthetic is able to support a lot more psi separation between the bearing and crankshaft. So dropping down a grade might not be the down grade the people think.
I am running 0w-20 Amsoil in my Taurus which is back speced for 20w oil. Not saying everybody go run 20w and not worry or think about what they are doing.............
Racing and stock vehicles are going to thinner......
Going thicker has it's drawbacks as well. Not as simple as thicker is better.
UOA anyone? Any towing or heavy loads hauled? A good synthetic is able to support a lot more psi separation between the bearing and crankshaft. So dropping down a grade might not be the down grade the people think.
I am running 0w-20 Amsoil in my Taurus which is back speced for 20w oil. Not saying everybody go run 20w and not worry or think about what they are doing.............
oilboy123 is probably right.
While I agree that it is no longer true that thicker is better and that a good syn can protect better at a lower viscosity - I just can't buy into a 20wt in a high horsepower street car like an LS series engine. I'd feel better with the GM spec 5 or 10W/30 than a 5W/20. That's just me though. I know drag racers use 10Wt or less for power, but again they don't drive them on the street for 5,000+ miles either. I've come a long way, like oilboy as far as oil (I used to use 20W/50 too) wt is concerned, so maybe in another few years I'll buy into the 20wt deal. I'm sure we'll going to see more 20Wt oil use by the automakers anyhow for better MPG and with Syn lubes it can be done rather safely.
While I agree that it is no longer true that thicker is better and that a good syn can protect better at a lower viscosity - I just can't buy into a 20wt in a high horsepower street car like an LS series engine. I'd feel better with the GM spec 5 or 10W/30 than a 5W/20. That's just me though. I know drag racers use 10Wt or less for power, but again they don't drive them on the street for 5,000+ miles either. I've come a long way, like oilboy as far as oil (I used to use 20W/50 too) wt is concerned, so maybe in another few years I'll buy into the 20wt deal. I'm sure we'll going to see more 20Wt oil use by the automakers anyhow for better MPG and with Syn lubes it can be done rather safely.
People use 5w-20 in 400 horsepower 4.6 DOHC Cobra engines and there are no problems... no reason why it won't work in 350 horsepower LS1 motors.
Originally Posted By: 98LSC32V
People use 5w-20 in 400 horsepower 4.6 DOHC Cobra engines and there are no problems... no reason why it won't work in 350 horsepower LS1 motors.
I didn't know that, 98LSC32V. Of course the LS engines are not DOHC, but doubt that makes any difference.
People use 5w-20 in 400 horsepower 4.6 DOHC Cobra engines and there are no problems... no reason why it won't work in 350 horsepower LS1 motors.
I didn't know that, 98LSC32V. Of course the LS engines are not DOHC, but doubt that makes any difference.
Originally Posted By: 98LSC32V
People use 5w-20 in 400 horsepower 4.6 DOHC Cobra engines and there are no problems... no reason why it won't work in 350 horsepower LS1 motors.
You think so? Did you see this UOA?
2006 Mustang
People use 5w-20 in 400 horsepower 4.6 DOHC Cobra engines and there are no problems... no reason why it won't work in 350 horsepower LS1 motors.
You think so? Did you see this UOA?
2006 Mustang
Originally Posted By: 98LSC32V
People use 5w-20 in 400 horsepower 4.6 DOHC Cobra engines and there are no problems... no reason why it won't work in 350 horsepower LS1 motors.
But you're forgetting that it's not enough to consider only the viscosity of the oil. There are other critical variables at play too. One important one would be the clearances designed into the engine. Another might be the specific composition of the bearings themselves. I'm not saying any given oil will or won't work in the subject application, but I would be careful when deviating from the mfr recommendations. At a minimum, I'd do UOA to confirm that my deviation was not in fact causing a problem for my engine as used under my unique circumstances.
People use 5w-20 in 400 horsepower 4.6 DOHC Cobra engines and there are no problems... no reason why it won't work in 350 horsepower LS1 motors.
But you're forgetting that it's not enough to consider only the viscosity of the oil. There are other critical variables at play too. One important one would be the clearances designed into the engine. Another might be the specific composition of the bearings themselves. I'm not saying any given oil will or won't work in the subject application, but I would be careful when deviating from the mfr recommendations. At a minimum, I'd do UOA to confirm that my deviation was not in fact causing a problem for my engine as used under my unique circumstances.
That is true, the LS1 has looser clearances than the Ford Modular motors, I still would have no reservations about running a good 5w-20 synthetic oil in an LS1.
I just got through pouring 5 quarts of 10W-30 into my GM L36 tonight; I've got to tell you, that oil seems thin enough!
With my oil OCD, I couldn't sleep at all with 5W-20 in my LS1.
I wonder what kind of car the topic LS1 is in anyway . . .
With my oil OCD, I couldn't sleep at all with 5W-20 in my LS1.
I wonder what kind of car the topic LS1 is in anyway . . .
- Status
Similar threads
