The LS comes with Ecotec...the base gets the 115hp pushrod.
The Danger of Increasing Viscosity
- Thread starter GoldenRod
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Yup...mine's the base one, with the good 'ole pushrod 2.2....not a bad engine, but with the piston slap on cool/cold mornings, doesn't sound too healthy!
My last 'in warranty' oil change will come in June; and the warranty is up in July. I'll put 5W-30 in June, and probably spike it with some cheap STP to give the oil some body for the summer - lots of driving and hauling stuff coming up this summer! I might try either the 10W-30/15W-40 mix or just straight Pennzoil 10W-40 next summer.
My last 'in warranty' oil change will come in June; and the warranty is up in July. I'll put 5W-30 in June, and probably spike it with some cheap STP to give the oil some body for the summer - lots of driving and hauling stuff coming up this summer! I might try either the 10W-30/15W-40 mix or just straight Pennzoil 10W-40 next summer.
If it's got such a seemingly serious mechanical problem, why dont you take it to get fixed before your warranty is up?
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Probably because at that rate of rotation they're hitting droplets that would normally just drop to the pan. They're creating their own windmill that creates other issues then your typical engine ..or it could be just one more thing to squeeze .09 hp out of it.
I believe that true "splash" lubrication (not the end of the rods for the piston/cylinder walls) was abandoned about 40 years ago (maybe longer).
Similar to Gary Allan, I think that the crank grinders are trying to reduce the wind resistance. Or, they are working on a misconception.
My current car has the Mazda KL 2.5 ltr V6 engine. The car is a 2001, but that engine model has been used since the early 90's.
My owners manual says i can use 5w30 all year round or 10w30 above 0*F. However if i look at the 1995 owners manual for the same engine, 5w30 is only good up to 50*F, and also says i can use 10w40 and 20w50. Same engine, different specs for different years.
So, i might feel safe using 10w40 or 15w40 in my car since it's been tried and tested. However i might not be so willing to dump a case of 20w50 in a brand new 2006 model with a new model engine. It just depends on your specific cars engine and it's history.
Having said all that, 10w40 is not likely to hurt anything in a car that allows for 10w30.
My owners manual says i can use 5w30 all year round or 10w30 above 0*F. However if i look at the 1995 owners manual for the same engine, 5w30 is only good up to 50*F, and also says i can use 10w40 and 20w50. Same engine, different specs for different years.
So, i might feel safe using 10w40 or 15w40 in my car since it's been tried and tested. However i might not be so willing to dump a case of 20w50 in a brand new 2006 model with a new model engine. It just depends on your specific cars engine and it's history.
Having said all that, 10w40 is not likely to hurt anything in a car that allows for 10w30.
I want to know why you would ever consider grinding a counterweight. You would throw the primary balance off and make the engine vibrate terribly, not to mention all the additional wear on the bearings.
Matt_S wrote: "I want to know why you would ever consider grinding a counterweight."
The grinding I have seen is on cranks that were cast with some "finishing" in mind, and it is done prior to final balancing.
The grinding I have seen is on cranks that were cast with some "finishing" in mind, and it is done prior to final balancing.
It's called knife edging. Good for a few HP above 5 or 6000 rpm. This is for all out engines and naturally, the crank is rebalanced.
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This is not a mythical event. I imagine it would depend on the design and age of the engine, but 20w-50 had a substantial effect on my Mitsu 3.0 when compared to 5w-20. It was "tighter" feeling.
In my opinion, it would depend on the number of cold starts/mile. The more starts/mile ..the more it will impact fuel economy. If you're a 50 mile/day commuter ..probably ZERO. If you're a 5 mile/day commuter ...probably substantial. That's my experience with engines that have a variance in economy due to visocity ..some do not (my jeep engines consume excess fuel just running anyway).
The 2.2L Ecotec does have a knocking noise on startup. I've done online research and people have attributed it to piston slap to timing chain problems...
Once I went from Mobil 5w30 to GC 0w30 the startup noise did not last as long. Now with Amsoil 5w30 HDD - I only get a few knocks on startup and it goes away within the first 5 seconds.
One thing for sure - this engine doesn't like operating cold! Feels like you are towing 5k pounds if you start off right from start. I always warm it up till the RPMs go below 1,000. Usually takes 10-20 seconds. Then takeoff and driving is MUCH smoother.
I seriously think this engine likes a heavier oil... Am tempted to try a 40 weight this summer.
As for MPG... I'm cranking out 36-39MPG average on way to work @70mph. In Iowa at 55-60mph I averaged 44+MPG. Best I got was 47MPG.
Once I went from Mobil 5w30 to GC 0w30 the startup noise did not last as long. Now with Amsoil 5w30 HDD - I only get a few knocks on startup and it goes away within the first 5 seconds.
One thing for sure - this engine doesn't like operating cold! Feels like you are towing 5k pounds if you start off right from start. I always warm it up till the RPMs go below 1,000. Usually takes 10-20 seconds. Then takeoff and driving is MUCH smoother.
I seriously think this engine likes a heavier oil... Am tempted to try a 40 weight this summer.
As for MPG... I'm cranking out 36-39MPG average on way to work @70mph. In Iowa at 55-60mph I averaged 44+MPG. Best I got was 47MPG.
I did just that that night. Drained out the Chevron Supreme 10W-30 and poured in 10W-40 MaxLife. So far the engine has NOT blown up yet. I only drove it about a mile after the oil change. The first thing I noticed was an increase in oil pressure at 185F idle speed from 45psi with 10W-30 to 60psi with the 10W-40.
The engine spins faster at startup then it did with 10W-30. That of course does not make sense, because lighter oils usually give you faster startups. The oil is a thin 10W-40 being 13.9 cSt @ 100C. In comparison, Havoline 10W-40 is 15.9 cSt @ 100C. I'll keep you guys posted on how it does.
GR
GoldenRod - I read the thread again and didn't see your car/engine. Probably missed it badly
Am I guessing you have the ecotec too?
45psi to 60psi... at 13.9cSt too... I wonder if that much of an increase is a bad thing? (No engineer here
). What psi would be considered bad or harmful for the oil pump?
45psi to 60psi... at 13.9cSt too... I wonder if that much of an increase is a bad thing? (No engineer here
I just put 10w40 maxlife in my 98 mazda 626 2.0. The only differance I have noticed so far is no oil consumption but more time will tell. My car does spec for 10w30 however the same engine in Austrailia specs 10w40 and 15w40.
Have you noticed the wording on the maxlife 10w40 ? " exceeds API SERVICE SM/SL ACEA A3 PERFORMANCE and all preceding api gasoline categories.Meets or exceeds all protection requirements of ILSAC GF-4."
[ May 05, 2006, 11:16 PM: Message edited by: leel ]
It's 3800V6 in a little Buick. I'm not worried about the increase in oil pressure, although I am surprised by the amount of increase.
Once the oil pressure is above specs, you're really not gaining anything. And if you reach the oil pump bypass pressure at a lower RPM than spec, you lowered the oil flow through the engine at RPMs above this point. Increased viscous heating in the bearings coupled with reduced flow isn't helping the bearings or the rollerized valvetrain any. Piston ring and valve guide seal are the only areas that might benefit if you don't see an proportional increase in oil temps. Will your engine blow up? No. Will it wear out sooner? Probably not. But you probably lost a little fuel efficency.
Oil is the "blood" of an engine. Viscosity is like the hematocrit. Too thin, and the heart has to be able to pump a little more per minute to keep up with the tissue requirements (but, that's not hard to do when the resistance is decreased with thinner fluid to pump). Too thick, and the heart has to pump HARDER to overcome the viscosity-induced drag, which takes more energy input. PLUS, the smallest capillaries may be underperfused, and sludged. Yep, that is the term used...it isn't sludge like oil sludge, but, it is areas of decreased/no flow. Athletes, blood doping, and the problems it creates are good examples of what can go wrong with having fluids too thick.
Below operating temps, oil is too viscous. This slow-flowing, too-thick oil is what is causing the increased wear at startup, and for the first 10-15 minutes of operation. TOO thick is obviously bad. What constitutes too thick, depends upon other things besides temperature. If you have an older engine with a bit of crud built up in some of the oil passageways, your engine might run cooler/better with THINNER oil, because thinner oil can squeeze through the narrow passageway better than thick oil (we use that information in medicine to provide better blood flow past narrowed arteries...you want the blood less viscous in order to perfuse the areas past the narrowing. And, no, this is not related to "blood thinners"...I wish EVERYONE would quit using that incorrect terminology...people are not on "blood thinners", they are on anticoagulants. Completely different subject.)
Anyway, I think there are very good reasons to steer away from using oil that might be too thick: and remember, they are ALL too thick at startup.
Below operating temps, oil is too viscous. This slow-flowing, too-thick oil is what is causing the increased wear at startup, and for the first 10-15 minutes of operation. TOO thick is obviously bad. What constitutes too thick, depends upon other things besides temperature. If you have an older engine with a bit of crud built up in some of the oil passageways, your engine might run cooler/better with THINNER oil, because thinner oil can squeeze through the narrow passageway better than thick oil (we use that information in medicine to provide better blood flow past narrowed arteries...you want the blood less viscous in order to perfuse the areas past the narrowing. And, no, this is not related to "blood thinners"...I wish EVERYONE would quit using that incorrect terminology...people are not on "blood thinners", they are on anticoagulants. Completely different subject.)
Anyway, I think there are very good reasons to steer away from using oil that might be too thick: and remember, they are ALL too thick at startup.
I have a 2002 Cavalier and have a little piston slap on startup in the winter. Have seen Havoline oil (I use 10W-30) reduce piston slap in other GMs. I also use close to a 50/50 mix (2 qts 15W-40 and about 2 1/2 qts 10W-30) truck oil with 10W-30 in the summertime. FWIW I had a 1996 S-10 2.2 OHV (same engine as Cavalier) and it had the piston slap issue. It never got any worse.
3800s have piston slap issues?
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Yes, I'm with 427 here. Once you're up against the relief you have no idea of what the flow rate is. You may assume that, given the higher pressure, that any flow would be higher. In reality what you have is a variable flow based on visc 24/7. The colder ..less flow ..hotter more flow ..but you just don't know how much since you've changed the flow dynamics of the circuit from series to parallel.
As he said, it may not alter your wear rate in a negitive manner ..but is something to ponder a minute or two in a more than casual manner.
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