Type of oil

[MrEl01]

Just for curiosity, what type of oil do you guys like to use in your car, conventional vs. synthetic ? Any particular brand ? Would either of them help with the consumption in the Northstar over the other ? I use 5W30 conventional in my Eldo, but for the wife's Towncar I prefer 0W20 full synthetic. I use Penzoil, myself. I know the brand doesn't really matter as long as the SAE numbers are correct. I've heard oil is oil, but my hand always reaches for that yellow jug.

[stsjoe]

not the dreaded oil thread

Joe

1030 maxlife

[abad95]

I have a '95 STS with 190000 miles and have been using Supertech brand from Walmart.

(Semi-Synthetic) 10W30 in summer,and 5w30 in winter.

I 've used Castrol brand in the past,and just recently switched to Valvoline MaxLife just because I change the oil often, and can't find the Supertech Semi Synthetic anymore.

I tried Penzoil way back in the day,and I didn't like the way the engine sounded.That could be a coincidence though.

If you change the oil often it shouldn't really matter what brand, but what grade.

Florin

[BodybyFisher]

not the dreaded oil thread

Joe

1030 maxlife

[kcd1184]

not the dreaded oil thread

Joe

1030 maxlife

I've been 10/30 maxlife also but decided to try Advanced Auto Parts comparable extended milage oil. $1.50 a quart difference.

Kent

[MrEl01]

not the dreaded oil thread

Joe

1030 maxlife

Please excuse my newbism, did not realise this was a sore spot.

[BodybyFisher]

not the dreaded oil thread

Joe

1030 maxlife

Please excuse my newbism, did not realise this was a sore spot.

Don't be insulted we are just kidding with you.... There is NO more emotional polarizing subject than oil, its sort of a private joke... That is unless you live in NY and you trying to tell a Yankee's fan that the Mets matter,

[Cadillac Jim]

I use Mobil 1 synthetic, 5W-30. I've had the car since I bought it new in October 1997. History:

I bought the car at Massey Cadillac in Downey, CA, which was then the biggest Cadillac dealer in the world. It still continues to be, but the owner's brother also has a Massey Cadillac in MI and I think that the ownership has merged, going by the web sites of Massey Cadillac. I originally used 10W-30 synthetic, dealer bulk. This oil is better than dino oil but not quite the same as Mobil 1, going by engine snap from idle and throttle response in low gear, although the effect of oil in these things is slight and takes somebody with a really good ear that drives the car every day. As far as I know, the car never burned a drop of oil while I was living in CA.

I continued with 10W-30 synthetic after moving to South Jersey in October 2000. The quality of this oil seemed spotty. In about 2002, the dealer started recommending 5W-30 for all Northstars and I started using that, asking for synthetic every oil change. Suddenly, over a period of about 3 months at about 75,000 miles in 2002 or 2003, the car tuned into an oil guzzer. It was burning a quart every 500 miles. I had suspicions about the detergent quality of the oil that was being used, because I would put in a quart of 5W-30 Mobil 1 about 500 miles out of an oil change and the car would smooth out like a junker that hadn't had its oil changed in years getting fresh oil -- it would start quicker, idle smoother, run better, and burn less oil after I put a quart of Mobil 1 in it. So, after it burnt the first quart, I started adding two cans of CD-2 detergent additive -- the stuff in the yellow 16 oz can, not the viscosity increaser. That improved the overall oil consumption to a quart every 1200 miles; I didn't have to add oil between 3,000 mile oil changes anymore. It did seem to have significant oil seepage at the oil pan or O-ring, as the oil pan was wet, but there were not spots on the garage floor. I ran that way until I developed head gasket problems in January 2006, and got a Jasper remanufactured engine in July 2006.

I've always run 5W-10 Mobil 1 in my new engine. I've had several oil changes and it has always stayed at the full mark.

I'm not going to give an opinion of what to do with your car. I do recommend synthetic oil and changing it before the oil life indicator (OLI) reads zero, and I start planning for an oil change at 50% of oil life left as indicated by the OLI.

[Ranger]

Many oil wars have been fought over that question Duff. Usually it is what is the "best" oil. That's why we run for cover when it comes up.

FWIW, I use conventional 10W30 SuperTech. I am pretty much in the oil is oil and gas is gas camp as well. Neither brand nor weight should do much for consumption (which is actually a good thing).

Here is what our old Guru (GM powertrain engineer) had to say about it.

Northstar Oil Consumption

"It is not unusual for a Northstar to use more oil than some other engines. It is a high performance engine and has to allow a little more oil to the top rings for lube as as well as down the 32 valve guides.

Design intent for oil consumption would put the engine at about 4000 miles per quart consumption but due to the variables in production parameters there are engines that will use 1 quart per 1000-1500 miles.... perfectly normal and acceptable... but more oil consumption than "intended". Nothing will be wrong with the engine but the continuous oil adds are aggravating. If this is the case then understand that the engine is probably going to run a long long time like that as the cylinder walls , rings, valve guides, etc. like all that oil that you are putting in and the continuous oil adds fortify the used oil in the sump and replenish the additive package in the oil that is slowly depleted under normal usage.

Comparing the 4.9 to the Northstar is an apples to oranges deal. The 4.9 is an excellent engine for it's purpose but does not offer nearly the performance, durability, fuel economy and emission control capability of the Northstar. The Northstar is a high output engine and likes to be "used".

The best way to minimize oil consumption in a Northstar is to keep the sump filled slightly low (many are continuously overfilled) by only checking the oil level when hot and only filling the sump with 7 quarts of oil (7.5 with a dry filter at a change.) A typical 8 quart fill at a change is "required" to put the oil level on the full mark when cold but is actually overfilling the crankcase promoting oil consumption.

Use conventional mineral oil (synthetic is not required at all) as it tends to provide better oil consumption.

An last, but not least, air the engine out frequently. It likes to be used and red-line upshifts at WOT help promote clean combustion chambers, exercise the piston rings to keep them free of carbon buildup and keep them mobile and to ensure the engine is broken in and maximum sealing is obtained. The Northstar does not like to be babied around. It likes to be run hard frequently with a WOT blast in merging or whatever.... Even engines reported to use 1 quart per 1500 miles tend to improve to 2500 miles per quart or better when subjected to a regular schedule of use and "abuse"...

----------

The subject of oil consumption really does not have a "final" answer. The fact is that there is some variability in oil consumption in all production engines.... regardless of who makes them on which continent. All the manufacturers recognize this and virtually all of them will call oil consumption as great as 1 quart in 1000 miles "normal" "acceptable" "allowable" "within production tolerances" etc... This doesn't mean that all engines will get 1000 MPQ or that the engine was designed to get 1000 MPQ...it just recognizes the fact that there are going to be some engines that get 1000 MPQ that will be perfectly fine upon disassembly and will have nothing "wrong" with them.

The variables that usually enter into oil consumption are primarily associated with the piston/ring/cylinder bore. The number of valves or type of valve actuation has little to do with it.

The single biggest variable and the one that has been discussed at great length on this forum is the cylinder bore finish or the cylinder honing pattern. The higher performance the engine is the more attention must be paid to the honing pattern and retention of oil on the cylinder walls to lubricate the piston and rings at full load , high RPM operation. The Northstar engine uses a very aggressive cylinder bore finish that tends to retain a lot of oil to protect the piston and rings. When the blocks are honed at the factory there is a tolerance in the bore finish due to the fact that the honing stones will wear and need replacement. A brand new stone gives a slightly more aggressive pattern than a "used" stone....so a block honed with new stones will have a more aggressive finish and most likely will use more oil.

Another variable is bore roundness. Like it or not, the bores tend to "move" slightly as the engine heats up and cools down and bolt tensions relax, etc. over time. All this contributes to slight bore out of roundness that is not bad or good...just different.

Carbon buildup in the rings and ring sealing are also variables that come into play with break in, operating schedule, type of oil used, etc.

The one thing that I can attest to is that many, many customer oil consumption complaint engines have been torn down with absolutely nothing wrong found. The engines are often reassembled and put into test cars and driven by the engineers and more often than not the high oil consumption does not repeat itself !!! The single biggest common cause seems to be breakin...or lack there of. Many, many oil consuming NOrthstar engines are "fixed" by some full throttle operation. I often joke about "driving it like you stole it" but it really is no joke. The Northstar engine was designed as a high performance engine to be run hard and fast. Those that are run hard typically exhibit excellent ring seal, little carbon build up and good oil economy. We have seen engines with tens of thousands of miles on them that the rings have not sealed or mated to the sides of the ring grooves because the operating schedule was so light duty. The moral here is to flog it .... often.

In any case, the nice thing about the engines with the more aggressive honing pattern is that the pistons, rings and bores will last forever. It is very common to tear down a 200,000 mile Northstar engine and still see the original honing pattern in the cylinders. There is never any sign of cylinder wall wear and the idea of a wear "ridge" at the top of the cylinder bore is something that is laughable on a Northstar.

The other nice thing about a little oil consumption is that it adds tremendous safety factor to the oil change interval. Nothing could be better for the engine than an occasional quart of fresh oil. You can take the worst oil on the market and add a fresh quart every 1000 miles and over the life of the engine the wear will be better than an engine run on the best oil with no adds between changes.

While no one in the engineering community wants high oil consumption the fact is that there is some variability in the oil consumption of an engine manufactured at the rate of 1200 per day. The specs of what is "normal" simply reflects this...it does not imply that all engines would get this or that something is wrong with and engine that gets more or less oil consumption.

There have been a lot of engineering changes over the years on the Northstar aimed at reducing the overall oil consumption and reducing the variability in the oil consumption of different engines. Many changes have been made to the honing process to make it more consistent. Changes to the piston and ring groove treatment have been made to make it more resistant to wear, pound out and micro welding at low oil retention rates. Regardless, there is still some variability.

One other thing that affects oil consumption, or the customers perception of oil consumption, is the move toward longer and longer change intervals. With the allowable change interval reaching as high as 12,500 miles on a 2003 Northstar if the oil life monitor is followed this could mean the addition of 3,4 or 5 quarts of oil to a very healthy engine. If the owner changes their oil every 2000 or 3000 miles, despite the oil life monitor recommendations, then they would not have to add any oil between changes. The oil consumption is the same....the amount added between changes is all that is different. Yet, many customers do not make the distinction. Field surveyors repeatedly show that "acceptable" oil consumption means "not having to add between changes"...whatever MPQ that is...???

The issue of oil consumption is very emotional , too, as many people perceive higher oil consumption as 'poor quality" or an indication that something is wrong. Blue smoke, fouling plugs, noise, etc...is a sign of something wrong. Using 1 quart in 1000 miles might be perfectly normal for an engine that has the high limit "rough" hone finish and is perfectly in spec...yet it will be perceived differently.

The Northstar engine in particular was designed to be a high performance engine and to perform well at high speeds and high loads. The engines are tested at loads and speeds for time periods few customers will ever be able to duplicate. It is unfortunate that the engineering that goes into making the engine capable of such running sometimes contributes to more oil consumption... especially as the production machining tolerances are taken into account.

The items mentioned about overfilling also apply. Make sure that the system is not overfilled as any excess oil will be pushed out the PCV. The best bet is to always check the oil hot and keep it midway between the add and full mark. Don't always top off and don't top off cold to the full mark as that will overfill the sump.

Hope this helps rather than adding more fuel to the fire... so to speak.

Incidentally, there is a lot in the message board / forum archives... check using "oil consumption" and read up. Always keep in mind that for every "oil burner" you read about on the internet there are 10,000 or more driving around perfectly fine that the people are not posting about... You are always going to read about the horror cases on the internet."

[JohnnyG]

No need for synthetic at all. In fact, since the introduction of Castrol sythetic, ALL oil is synthetic........so what does it matter?

Chevron Supreme (conv.) or Trop Arctic, the two best around!

Did I REALLY just reply to a "which oil" thread? I couldn't help myself I guess. Sorry!!!

[Ranger]

Did I REALLY just reply to a "which oil" thread?

Not only did you respond, but you said "best".

[Cadillac Jim]

I got started on synthetic oil when I was driving a Quad 4 HO, which uses 5W-30. There was noticeably more snap to the engine with synthetic (Mobil 1) 5W-30 as compared to dino 5W-30, so I always used synthetic. With the Northstar, the difference is still there, though less so on the larger engine. This is probably related to the "energy efficiency" sales point for synthetic oil. In other words, I use synthetic to wring the last bit of performance and gas mileage out of my engine, not because I think it's better for it.

Note in Ranger's quote from a guru post that there is a lot of emphasis and repetition on using the engine, and WOT upshifts at redline are mentioned. When I had an oil burning problem with my old engine I took this to heart and it helped. I used the CD-2 detergent additive because I had doubts about the quality of the oil or that the oil was actually changed, and I don't think that the CD-2 alone reduced oil consumption. Note that I mentioned that WOT use is a good idea, if you verify that the engine is in good shape first. I have found that a trip of 500 miles or more at 55 mph or faster is very good for any engine; it has the same benefits as WOT operation and you get to see a lot more scenery.

[WarrenJ]

Please excuse my newbism, did not realise this was a sore spot.

I'm certain you're excused and I don't mean to make light of your concerns, but we enjoy (or not) this sort of stuff from time to time. :lol:

Just sit back and watch!

Okay folks, have at it!

Regards,

Warren

[Regis]

Jim,

A 500 mile trip always does a car good..... unless you happen across a near sited deer that wants to inspect your grill wreath up close. From what I recall (someone correct me) it isn't nor does it accomplish the same as performing WOTs. My experiences would support the differences but I'm no expert. Now a 500 mile trip including WOTs..... now we're talkin.

Et al,

As far as oil goes I'm pretty much always around the 1000-1500 MPQ consumption rate. Recently I've switched from Pennzoil 10W-30 to Shell conventional 10W-30 to save a few bucks. In the past I've gone stretches with Valvoline and Castrol (conventional) but used Pennzoil the longest. I use the OLM (Oil Life Monitor) but sometimes I change the oil early and other times 1000-2000 miles over. I'll bet that last bit would have some people sweating bullets.

[Cadillac Jim]

I do agree with Regis that WOTs and 500+ mile road trips do different things for your car. The WOT is better at cleaning out your rings, which is the key for oil consumption. Both clean your combustion chambers and plugs. The 500+ mile trip is better at cleaning out your cat and oxygen sensors. There are lots of other differences, too, so, like Regis says, both are best. If a 500+ mile trip is not reasonably convenient, just nail it good on a few freeway on-ramps.

I have had several deer inspect my car, one from about 3 feet over the hood. Only one had a close encounter of the fourth kind with my front bumper, and, unfortunately, he died as we and a bystander watched helplessly. There was no trace of damage, so I was lucky. The key is not to drive at night, to keep an eye open, and note that whenever a few deer cross the road there will likely be a straggler so slow down and watch for it. And, when you see a deer crossing sign, it's there because people hit deer there occasionally.

I always change my oil when there is still plenty left on the OLI but my wife lets her 1999 Pontiac GT with 3.4 HO V6 tell her when to change oil, and it isn't often. Her car is fine. It's better after I borrow it and drive out a tank of gas, but that's not the oil. Every time I check her oil, it doesn't need any, it's clear, and it smells OK, not musty or sludgy.

[BodybyFisher]

The high speed driving is great for the engine but the WOT's using the low gear to slow the car down to 45 exercises the rings and pulls carbon out of the cylinder due to buffeting negative pressure..

I only do the WOT procedure a few times a year, my oil consumption isnt bad, the case half leak is where I loose my oil

[WarrenJ]

... That is unless you live in NY and you trying to tell a Yankee's fan that the Mets matter,

But the Mets *DO* matter . . . . . most notably when they are pummelled by the Yankees.

[clarkz71]

I almost missed an oil thread. I used to use Mobil 1 10/30.

But I can't get myself to go more then 4000 miles between changes, so.......

Now I use (the best) Shell Rotella 10/30

[Poobah]

not the dreaded oil thread

Joe

1030 maxlife

Please excuse my newbism, did not realise this was a sore spot.

Don't be insulted we are just kidding with you.... There is NO more emotional polarizing subject than oil, its sort of a private joke . . .

(. . . and the second most emotionally emotionally polarizing subject is car wax.)

I use the oil that is recommended in the owners manual and printed on the oil filler cap. I change it when the oil life monitor says to. I figure if that's good enough for the people who design, manufacture, and warranty the engine, it's good enough for me. After all, they know a whole lot more about oil than I do!

[jackc]

I'm currently running Castrol GTX 10w30.

I think I'm going to try Rotella 10w30 for my next change, if I can find any.

[WarrenJ]

Sunday was my birthday. I am now officially an "old fart."

How do I know this? Because an "oil thread," at long last, has finally failed to produce even a skirmish, never mind a war. Has hell frozen over?

Maybe I'll simply end it all . . . .

Regards . . . .

[JimD]

Sunday was my birthday. I am now officially an "old fart."

What is the entry age for that status?

How do I know this? Because an "oil thread," at long last, has finally failed to produce even a skirmish, never mind a war. Has hell frozen over?

Or.... those who were passionate about brand 'x', viscosity 'y', for reason 'z' have moved on. Or.... folks have discoverd the Search function. Or.... people are actually reading the owner's manual and the oil filler cap.

Maybe I'll simply end it all . . . .

Reconsider. Tomorrow could bring a fuel octane thread.

[WarrenJ]

Oops! Double post.

[WarrenJ]

Sunday was my birthday. I am now officially an "old fart."

What is the entry age for that status?

How do I know this? Because an "oil thread," at long last, has finally failed to produce even a skirmish, never mind a war. Has hell frozen over?

Or.... those who were passionate about brand 'x', viscosity 'y', for reason 'z' have moved on. Or.... folks have discoverd the Search function. Or.... people are actually reading the owner's manual and the oil filler cap.

Maybe I'll simply end it all . . . .

Reconsider. Tomorrow could bring a fuel octane thread.

You probably think I can't handle your multiple [\QUOTE\] thingies. Well, you're right!

OTOH, I *DO* use a top tier gasoline.

Let the wars begin!

Regards,

Warren

[JimHare]

And, when you see a deer crossing sign, it's there because people hit deer there occasionally.

What I wanna know is, how do the darn deer know to cross where the sign is? Seems to me they like to mix us up by crossing at odd other places - like RIGHT AROUND THAT darn CORNER I JUST TOOK AT 70!!!! Aiiiiiiiiiiiiiiiiiiiiii!

"Grilled" Venison is my greatest fear around here. The darn deer just walk right out on ya looking stupid.