When Should I Start Using High Mileage Oil

[JohnnyG]

On the other hand using synthetic oils on a car that doesn't demand it won't hurt anything, BUT there will be no magical earnings/positive effects from using synthetics because the only advantage in using synthetic is a slightly higher temperature breakdown resistance.

Jan, you are mostly correct, and I am not going against bbob or his recommendations for dino oil, but two thing sort of "cloud" the issue.

The most important one to us Northstar drivers is the type and amount of Viscosity Index Improvers present in the oil. These, if used in excess (to make a poor dino oil perform well) or if not manufactured up to the highest standards ( read: cheap dino oil), OR due to using too wide a viscosity spread like 5W-40, were the main cause of ring carbonization and stuck ring packs. Synthetic blends which in reality are now ALL called synthetic (thank you again Castrol) and what we all encounter at WalMart, could achieve the required viscosity ranges with FEWER additives, hence, in my reasoning, less carbon deposits. Now we move up to GF-5, which MANDATES minimal ring deposits! This can ONLY be achieved by using some type of synthetic blend oil. Same deal with 0W-whatever/energy conserving....you can no longer do that with VII additives under GF-5, if it were ever possible with dino oil.

And 2, minor issue here, passing the SM standard requires backward compatibility with all previous API standards, so no worries about pre 2000 flat tappet Northstar engines. The ZDDP was supplemented with moly and other extreme pressure additives, and projected catalytic converter life was extended in the process. So now we are about to encounter SN oils at the local store, they are also backwards compatible with all previous API standards.

[Texas Jim]

....Then again, I have a suspicion that it may be a case of "FOLLOW THE MONEY"....

When you follow the money you will bump into several groups of well paid ethanol lobbyists inside the beltway over there in dismal swamp land.

One option is to deny this administration a congressional majority on 11/2/2010.

Another option is to make certain this is a one-term administration on 11/6/2012.

The retail merchants association has to be all over this ruling because your local gasoline retailer will be faced with the burden of fronting the money to install yet another storage tank in the ground. Thousands of storage tanks.

Guess who will eventually pay for that!

It all comes down to politics. And politics today is a synonym for.... but I digress.

Vote your check book balance.

And not the balance today but the balance 5 or 10 or 20 years from today.

[sOAP BOX MODE = OFF]

Those three things I "WILL BE" doing...

You can take that to the bank... ..

[Jan Olsson]

In general, I would agree with you. The exception is my 04 XLR 4.6 N-Star which does specify Mobil One Synthetic 5W-30. This oil is also spec'd for newer Corvette engines with oil coolers. The other comment is that refined Dino oil has inherently higher levels of naturally occurring trace elements [contaminants] as opposed to "manufactured" synthetic oils. In this case the poster says that uses his DTS in high rpm/performance in the Hot South [Texas] environment so I think he might benefit from synthetic. So while I agree synthetic is probably overkill for most applications, I like to have the wide margin to spec limits. Tack sa mycket

Your XLR is no exception. The reason synthetic is specified is that you don't have an engine oil cooler, or a smaller one than you would have if it was speced with "any" oil.

Same goes for the Vettes.

The STS-V for instance has an engine oil cooler and is speced with synthetic oil.

[Jan Olsson]

That is true...I also do a good bit of driving in the desert SW.

New Mexico, Arizona and Southern Utah..

I think I will just keep using the synthetic in it.

It has done well so far and I didn't see any reason that anyone put forth in a post to give me reason to change what has worked well so far.

PS:..I was in Raleigh the other day on vacation.

The OLM takes that in account, whether you are using a dino or synthetic oil. If your car was speced for a synthetic oil then you would see longer oil-change intervals because of the benefits from a heat perspective.

But since your car doesn't call for a synthetic blend, then your OLM still wants you to change the oil "early". This is the reason why there is no use for you to use synthetic, on the other hand your car won't be harmed from it.

[Cadillac Jim]

The 1997 Cadillac owner's manual and FSM say that up to 15% ethanol is OK. Apparently cars have been designed to tolerate that much for a long time.

There are a few things about synthetic oil that hasn't yet been mentioned, including slightly higher fuel economy and a lower sludge susceptibility. The fuel economy thing is due to some combination of lower mass density or lower engine drag, something I could feel in my previous engine, a Quad 4 HO, and can easily detect in my Northstar, and that translates to slightly better performance, again something that was obvious in the Quad 4 HO and noticeable in my Northstar. I've been using 5W-30 synthetic since I bought my car. I never tried 10W-30 synthetic in either of them; the Quad 4 HO recommended 5W-30 and the dealer recommended 5W-30 Mobil 1 in my Northstar.

The higher heat breakdown temperature and lower sludge susceptibility of synthetic oil may translate to less likelihood of sticking rings in cars that are driven lightly 100% of the time.

[Jan Olsson]

The higher heat breakdown temperature and lower sludge susceptibility of synthetic oil may translate to less likelihood of sticking rings in cars that are driven lightly 100% of the time.

Seems like the only REAL reason to use the synthetics. My STS runs on semi-synthetic 5W-30 but that is because I can't get my hands on a dino-oil with that viscosity (I drive quite hard).

If I lived in the US then I would be happy to use synthetic oils but over here the price is twice as much for synthetic versus dino-oils.

[Jan Olsson]

The most important one to us Northstar drivers is the type and amount of Viscosity Index Improvers present in the oil. These, if used in excess (to make a poor dino oil perform well) or if not manufactured up to the highest standards ( read: cheap dino oil), OR due to using too wide a viscosity spread like 5W-40, were the main cause of ring carbonization and stuck ring packs.

They did all kinds of extensive testing when they validated the Northstar, even with ZDDP depleted oils. 5W-30 and 10W-30 don't really need high levels of viscosity improvers simply because there isn't a great span in viscosities. 10W-40/20W-50 on the other hand do. But that was mainly a problem of the past as I mentioned earlier.

We are all familiar with the WOT-treatment, one of the benefits is that rings will be excerciced.

On a Northstar they tend to stick not because of dino-oils but because of the drivning habits.

Synthetic blends which in reality are now ALL called synthetic (thank you again Castrol) and what we all encounter at WalMart, could achieve the required viscosity ranges with FEWER additives, hence, in my reasoning, less carbon deposits. Now we move up to GF-5, which MANDATES minimal ring deposits! This can ONLY be achieved by using some type of synthetic blend oil. Same deal with 0W-whatever/energy conserving....you can no longer do that with VII additives under GF-5, if it were ever possible with dino oil.[/quote

You are right that a synthetic oil needs fewer additives than a dino oil and that's a good thing. But the engine is still validated and constructed for "older oils" i.e. the engine manages dino-oil. If you have a new car then it would be crazy to use a API-SF oil. But an engine speced with an API-SF oil don't still don't benefit from synthetic oils. Perhaps a bit cleaner inside but the engine can cope

I had a -93 STS for instance, I always ran it on 10W-30 dino-oil. After 150000 miles the engine looked as new inside, just small amounts of deposits on the pistons.

And 2, minor issue here, passing the SM standard requires backward compatibility with all previous API standards, so no worries about pre 2000 flat tappet Northstar engines. The ZDDP was supplemented with moly and other extreme pressure additives, and projected catalytic converter life was extended in the process. So now we are about to encounter SN oils at the local store, they are also backwards compatible with all previous API standards.

Not exactly right. The API-standards don't call for ZDDP or other high pressure additives so the oil MAY contain high pressure additives or not. Todays engines don't need high pressure additives because of changes in the design. There are many many cases on the internet where car owners suddenly experiences worn-down cams.

I'll quote the guru:

Your english is fine. Better than my German or whatever.....LOL

You are correct in assuming that the later API grades such as SL or SM are "better" and , as such, supercede the earlier grades. That is conventional wisdom and is pretty much the case as one of the API requirements is that "improved" performance grades supercede prior grades and are always backwards compatible.

Having said that.....the current crop of oils "rated for gasoline engines" that are on the shelf in the most obvious locations in the stores are also "fuel economy" oils. Any oil with the ILSAC "starburst" symbol that says "for gasoline engines" is a bit of a hybrid....those oils meet the latest API performance specs, have the minimum allowable ZDP (to prevent catalyst contamination) and have friction modifiers in the oil for fuel economy improvement.

The difference is that the API specs just relate to the oil's performance as tested on gasoline engines. API specs have nothing to do with friction modifiers or MINIMUM ZDP levels. The API specs just have minimum performance specifications based on actual engine testing.

Understand that the API performance specs have a lot of requirements besides just "wear protection". Most all of the improvement in the latest grades is in the area of temperature protection. The latest oils will still perform at hotter and hotter engine temperatures. So they are "better" in that the older oils might start to oxidize and give up around 290 degrees F and the latest oils will still function well at 310 or 315 degrees F. They are not "better" in that they give more wear protection.....they just have better high temperature resistence, among other things.

More modern, current production engines are designed to run with the minimum ZDP oils and friction modified oils. Clearances are changed, designs are changed to add roller followers everywhere that are not ZDP dependent for preventing wear, wear surfaces are hardened where necessary, etc.....

Older engines designed for the SF and SG oils that had more ZDP in them are not as well protected against ZDP depleted oils.

So...technically the older engines should be OK with the new SM oils since the SM oils "technically" supercede the older oils and are backwards compatible. But the newer oils probably are " barely" adequate in terms of anti-wear additives such as ZDP. If the engine is perfect inside it will likely be fine. But if the engine is marginal for wear the ZDP depleted oil MIGHT cause a problem and accelerate wear. Certainly you would not want to use the newer ZDP reduced oils for long change intervals in the older engines.

An older 93 Northstar, for instance, has 32 rubbing element tappets (flat tappets) that require much more ZDP for protection against wear than the 2000 and later Northstars with roller tappets.

If you want to be sure your engine has the best wear protection you can do two things. One, use one of the non-"gasoline engine" oils such as the diesel Rotella or Delvac or Delo oils. Those oils have much more anti-wear protection since they are also certified for diesel use. The other thing you can do is to spike the oil you are using with extra ZDP by adding a pint or quart of GM EOS (General Motors Engine Oil Supplement). The EOS is available at any GM parts counter and is sold as an assembly lube. It is basically plain motor oil with a high concentration of ZDP that will fortify any crankcase fill with the extra ZDP desired for more anti-wear protection. It is the only oil "additive" I would ever recommend as it is specifically designed for this purpose.

If you look at the container of Rotella/Delvac/Delo oil you will see in the fine print that it meets all the API diesel performance specs (combinations of the letters CC and CD, etc.) AND it meets the latest gasoline API performance specs such as SL or SM. Now look at the ILSAC "for gasoline engine" oil across the isle in the autoparts store. Read the fine print. It meets the API gasoline SM specs but does NOT meet any of the diesel performance specs. The diesel specific oil is a much "better" product in terms of wear protection if your engine needs it. Diesels have a much greater need for anti-wear protection due to the soot and combustion byproduct contamination of the oil due to the high compression and high cylinder pressures of the diesel engine, so the oils for diesels have to be much better.

I would recommend the Rotella/Delvac/Delo oils for the 93-99 Northstars, personally. The latest ILSAC fuel economy oils are getting very low in ZDP concentration. Fine with the newest engines on the road but not so fine for a 93 Northstar.

You can get the Rotella/Delvac/Delo oils in 10W30 for your engine but they are much harder to find. Check a truck stop or large equipment supplier. If all you can find is the 15W40 version of the Rotella/Delvac/Delo that is fine in the 93 Northstar. The oil is not that much thicker to hurt anything unless you live in the far north and need to cold start at -40.

The other option is to use one of the "severe service" oils marketed by Mobil that are designed for longer change intervals and marketed as such. If you read those bottles you will notice that they also do NOT meet the ILSAC "for gasoline engine" use as they do not have the ILSAC starburst symbol. That is because those oils designed specifically for longer change intervals also have more ZDP in them that excedes the amount allowed for the ILSAC starburst designation.

I would recommend the conventional diesel Rotella/Delvac/Delo oils. I personally use the Delvac (Mobil) in most everything around the house.

[KHE]

One option is to deny this administration a congressional majority on 11/2/2010.

Another option is to make certain this is a one-term administration on 11/6/2012.

The retail merchants association has to be all over this ruling because your local gasoline retailer will be faced with the burden of fronting the money to install yet another storage tank in the ground. Thousands of storage tanks.

Guess who will eventually pay for that!

It all comes down to politics. And politics today is a synonym for.... but I digress. Vote your check book balance. And not the balance today but the balance 5 or 10 or 20 years from today.

[sOAP BOX MODE = OFF]

I couldn't agree more!

[Texas Jim]

The OLM takes that in account, whether you are using a dino or synthetic oil. If your car was speced for a synthetic oil then you would see longer oil-change intervals because of the benefits from a heat perspective.

But since your car doesn't call for a synthetic blend, then your OLM still wants you to change the oil "early". This is the reason why there is no use for you to use synthetic, on the other hand your car won't be harmed from it.

It is true that my car does not SPECIFY Synthetic oil.

The owners manual says to use DINO oil...

I did that for a good while...then switched to synthetic.

I usually change the oil when the OLM gets to about 35 percent.

I know you are supposed to wait till it is almost -0- percent...but I just can't do that..

I can not bring myself to run the car that many miles without changing the oil.

I feel that it is better to be safe than sorry.

This last oil change...I "DID" run it down to 10 percent...

That was over 10,000 miles.

I will never do that again.

I worried about it constantly after it got below 35 percent. (ha ha)

[Texas Jim]

The 1997 Cadillac owner's manual and FSM say that up to 15% ethanol is OK. Apparently cars have been designed to tolerate that much for a long time.

There are a few things about synthetic oil that hasn't yet been mentioned, including slightly higher fuel economy and a lower sludge susceptibility.

The fuel economy thing is due to some combination of lower mass density or lower engine drag, something I could feel in my previous engine, a Quad 4 HO, and can easily detect in my Northstar, and that translates to slightly better performance, again something that was obvious in the Quad 4 HO and noticeable in my Northstar. I've been using 5W-30 synthetic since I bought my car. I never tried 10W-30 synthetic in either of them; the Quad 4 HO recommended 5W-30 and the dealer recommended 5W-30 Mobil 1 in my Northstar.

The higher heat breakdown temperature and lower sludge susceptibility of synthetic oil may translate to less likelihood of sticking rings in cars that are driven lightly 100% of the time.

I have noticed that also from various oil changes.

When using synthetic, it seems run just a little bit better and on a trip...gets about .5 MPG better mileage, overall.

It may be all in my head...but I don't think so. ..

[Jan Olsson]

The OLM takes that in account, whether you are using a dino or synthetic oil. If your car was speced for a synthetic oil then you would see longer oil-change intervals because of the benefits from a heat perspective.

But since your car doesn't call for a synthetic blend, then your OLM still wants you to change the oil "early". This is the reason why there is no use for you to use synthetic, on the other hand your car won't be harmed from it.

It is true that my car does not SPECIFY Synthetic oil.

The owners manual says to use DINO oil...

I did that for a good while...then switched to synthetic.

I usually change the oil when the OLM gets to about 35 percent.

I know you are supposed to wait till it is almost -0- percent...but I just can't do that..

I can not bring myself to run the car that many miles without changing the oil.

I feel that it is better to be safe than sorry.

This last oil change...I "DID" run it down to 10 percent...

That was over 10,000 miles.

I will never do that again.

I worried about it constantly after it got below 35 percent. (ha ha)

There is a typical safety factor 2, but of course one doesn't want to go there. I.e. drive past 0%

I believe that your car doesn't need dino-oil specifically, both kinds will do fine.

I suppose the specifications only says that you should use oils with the ILSAC star-burst/energy conserving oil?

The newer Northstars only says "Change oil now". Then it is recommended that you change within the next 200 miles.

The older ones had an additional warning "Change oil soon" at 10% estimated life left, have you ever seen that warning?

[Jan Olsson]

I have noticed that also from various oil changes.

When using synthetic, it seems run just a little bit better and on a trip...gets about .5 MPG better mileage, overall.

It may be all in my head...but I don't think so. ..

I'm sure that your observations are correct.

I would like to clarify that I have nothing against synthetic oils (except from when older engines starts to leak after a change is made between dino and synthetic oils) but there is a difference between necessity (newer Caddies) and subjectivity (older Caddies).

And I still insist that owners of older Northstar engines don't rely on the thought that a higher API-grade is better than an older one. That is only true on todays, most up-to-date engines.

[Texas Jim]

I have noticed that also from various oil changes.

When using synthetic, it seems run just a little bit better and on a trip...gets about .5 MPG better mileage, overall.

It may be all in my head...but I don't think so. ..

I'm sure that your observations are correct.

I would like to clarify that I have nothing against synthetic oils (except from when older engines starts to leak after a change is made between dino and synthetic oils) but there is a difference between necessity (newer Caddies) and subjectivity (older Caddies).

And I still insist that owners of older Northstar engines don't rely on the thought that a higher API-grade is better than an older one.

That is only true on todays, most up-to-date engines.

Mine is a 2006.

Reckon that would qualify as "UP TO DATE"..

The 2007 model (and newer) is supposed to use Synthetic oil only...it even says so on the oil filler cap.

There may be differences, but "I" don't know of "ANY" difference between the 2006 and the 2007 engines.

I do run mine harder than most Cadillac owners do.

As I said earlier...sometimes it is run at 100mph or more for hours at a time, when driving out west in the wide open desert.

And it is not unusual for it to go to 7000 RPM when entering a freeway.....

I love the sound of the NorthStar when it is winding up...

[CarlaValentine]

I love the sound of the NorthStar when it is winding up...

So do I. It's one of the most beautiful sounds I've ever heard!

[BodybyFisher]

The most important one to us Northstar drivers is the type and amount of Viscosity Index Improvers present in the oil. These, if used in excess (to make a poor dino oil perform well) or if not manufactured up to the highest standards ( read: cheap dino oil), OR due to using too wide a viscosity spread like 5W-40, were the main cause of ring carbonization and stuck ring packs.

They did all kinds of extensive testing when they validated the Northstar, even with ZDDP depleted oils. 5W-30 and 10W-30 don't really need high levels of viscosity improvers simply because there isn't a great span in viscosities. 10W-40/20W-50 on the other hand do. But that was mainly a problem of the past as I mentioned earlier.

We are all familiar with the WOT-treatment, one of the benefits is that rings will be excerciced.

On a Northstar they tend to stick not because of dino-oils but because of the drivning habits.

Synthetic blends which in reality are now ALL called synthetic (thank you again Castrol) and what we all encounter at WalMart, could achieve the required viscosity ranges with FEWER additives, hence, in my reasoning, less carbon deposits. Now we move up to GF-5, which MANDATES minimal ring deposits! This can ONLY be achieved by using some type of synthetic blend oil. Same deal with 0W-whatever/energy conserving....you can no longer do that with VII additives under GF-5, if it were ever possible with dino oil.[/quote

You are right that a synthetic oil needs fewer additives than a dino oil and that's a good thing. But the engine is still validated and constructed for "older oils" i.e. the engine manages dino-oil. If you have a new car then it would be crazy to use a API-SF oil. But an engine speced with an API-SF oil don't still don't benefit from synthetic oils. Perhaps a bit cleaner inside but the engine can cope

I had a -93 STS for instance, I always ran it on 10W-30 dino-oil. After 150000 miles the engine looked as new inside, just small amounts of deposits on the pistons.

And 2, minor issue here, passing the SM standard requires backward compatibility with all previous API standards, so no worries about pre 2000 flat tappet Northstar engines. The ZDDP was supplemented with moly and other extreme pressure additives, and projected catalytic converter life was extended in the process. So now we are about to encounter SN oils at the local store, they are also backwards compatible with all previous API standards.

Not exactly right. The API-standards don't call for ZDDP or other high pressure additives so the oil MAY contain high pressure additives or not. Todays engines don't need high pressure additives because of changes in the design. There are many many cases on the internet where car owners suddenly experiences worn-down cams.

I'll quote the guru:

Your english is fine. Better than my German or whatever.....LOL

You are correct in assuming that the later API grades such as SL or SM are "better" and , as such, supercede the earlier grades. That is conventional wisdom and is pretty much the case as one of the API requirements is that "improved" performance grades supercede prior grades and are always backwards compatible.

Having said that.....the current crop of oils "rated for gasoline engines" that are on the shelf in the most obvious locations in the stores are also "fuel economy" oils. Any oil with the ILSAC "starburst" symbol that says "for gasoline engines" is a bit of a hybrid....those oils meet the latest API performance specs, have the minimum allowable ZDP (to prevent catalyst contamination) and have friction modifiers in the oil for fuel economy improvement.

The difference is that the API specs just relate to the oil's performance as tested on gasoline engines. API specs have nothing to do with friction modifiers or MINIMUM ZDP levels. The API specs just have minimum performance specifications based on actual engine testing.

Understand that the API performance specs have a lot of requirements besides just "wear protection". Most all of the improvement in the latest grades is in the area of temperature protection. The latest oils will still perform at hotter and hotter engine temperatures. So they are "better" in that the older oils might start to oxidize and give up around 290 degrees F and the latest oils will still function well at 310 or 315 degrees F. They are not "better" in that they give more wear protection.....they just have better high temperature resistence, among other things.

More modern, current production engines are designed to run with the minimum ZDP oils and friction modified oils. Clearances are changed, designs are changed to add roller followers everywhere that are not ZDP dependent for preventing wear, wear surfaces are hardened where necessary, etc.....

Older engines designed for the SF and SG oils that had more ZDP in them are not as well protected against ZDP depleted oils.

So...technically the older engines should be OK with the new SM oils since the SM oils "technically" supercede the older oils and are backwards compatible. But the newer oils probably are " barely" adequate in terms of anti-wear additives such as ZDP. If the engine is perfect inside it will likely be fine. But if the engine is marginal for wear the ZDP depleted oil MIGHT cause a problem and accelerate wear. Certainly you would not want to use the newer ZDP reduced oils for long change intervals in the older engines.

An older 93 Northstar, for instance, has 32 rubbing element tappets (flat tappets) that require much more ZDP for protection against wear than the 2000 and later Northstars with roller tappets.

If you want to be sure your engine has the best wear protection you can do two things. One, use one of the non-"gasoline engine" oils such as the diesel Rotella or Delvac or Delo oils. Those oils have much more anti-wear protection since they are also certified for diesel use. The other thing you can do is to spike the oil you are using with extra ZDP by adding a pint or quart of GM EOS (General Motors Engine Oil Supplement). The EOS is available at any GM parts counter and is sold as an assembly lube. It is basically plain motor oil with a high concentration of ZDP that will fortify any crankcase fill with the extra ZDP desired for more anti-wear protection. It is the only oil "additive" I would ever recommend as it is specifically designed for this purpose.

If you look at the container of Rotella/Delvac/Delo oil you will see in the fine print that it meets all the API diesel performance specs (combinations of the letters CC and CD, etc.) AND it meets the latest gasoline API performance specs such as SL or SM. Now look at the ILSAC "for gasoline engine" oil across the isle in the autoparts store. Read the fine print. It meets the API gasoline SM specs but does NOT meet any of the diesel performance specs. The diesel specific oil is a much "better" product in terms of wear protection if your engine needs it. Diesels have a much greater need for anti-wear protection due to the soot and combustion byproduct contamination of the oil due to the high compression and high cylinder pressures of the diesel engine, so the oils for diesels have to be much better.

I would recommend the Rotella/Delvac/Delo oils for the 93-99 Northstars, personally. The latest ILSAC fuel economy oils are getting very low in ZDP concentration. Fine with the newest engines on the road but not so fine for a 93 Northstar.

You can get the Rotella/Delvac/Delo oils in 10W30 for your engine but they are much harder to find. Check a truck stop or large equipment supplier. If all you can find is the 15W40 version of the Rotella/Delvac/Delo that is fine in the 93 Northstar. The oil is not that much thicker to hurt anything unless you live in the far north and need to cold start at -40.

The other option is to use one of the "severe service" oils marketed by Mobil that are designed for longer change intervals and marketed as such. If you read those bottles you will notice that they also do NOT meet the ILSAC "for gasoline engine" use as they do not have the ILSAC starburst symbol. That is because those oils designed specifically for longer change intervals also have more ZDP in them that excedes the amount allowed for the ILSAC starburst designation.

I would recommend the conventional diesel Rotella/Delvac/Delo oils. I personally use the Delvac (Mobil) in most everything around the house.

Thanks for posting this!

[Jan Olsson]

Mine is a 2006.

Reckon that would qualify as "UP TO DATE"..

Oh yes, older ones are pre-2000 cars. Especially cars from the early 90's since the later ones have other clearences/surface treatments to match the newer oils better.

I do run mine harder than most Cadillac owners do.

As I said earlier...sometimes it is run at 100mph or more for hours at a time, when driving out west in the wide open desert.

And it is not unusual for it to go to 7000 RPM when entering a freeway.....

I love the sound of the NorthStar when it is winding up...

Remember when the guru talked about their 300h full throttle tests?

The engines was also a quarter of oil short and angled at 45°

I think your car will be fine with what is recommended

[BodybyFisher]

One option is to deny this administration a congressional majority on 11/2/2010.

Another option is to make certain this is a one-term administration on 11/6/2012.

The retail merchants association has to be all over this ruling because your local gasoline retailer will be faced with the burden of fronting the money to install yet another storage tank in the ground. Thousands of storage tanks.

Guess who will eventually pay for that!

It all comes down to politics. And politics today is a synonym for.... but I digress. Vote your check book balance. And not the balance today but the balance 5 or 10 or 20 years from today.

[sOAP BOX MODE = OFF]

I couldn't agree more!

Definately, get rid of the America hating radicals, NOW, the US is the LAST bastion of hope, enforce our current laws, outlaw affirmative action, and base everything on merit, including mortgage loan approval, if you don't have the credit history, income, downpayment or job security, you RENT!

[Texas Jim]

Definately, get rid of the America hating radicals, NOW,

the US is the LAST bastion of hope, enforce our current laws, outlaw affirmative action, and base everything on merit, including mortgage loan approval, if you don't have the credit history, income, downpayment or job security, you RENT!

Absolutely...

Mike,

You should see some of the billboards around here...

There is a picture of George Bush ... kinda leaning forward a little..smiling...looking at the camera...with the caption....

"MISS ME YET?"

I take it to mean..."Hey...you thought "I" was bad...look what you have "NOW"... :D

[JohnnyG]

And I still insist that owners of older Northstar engines don't rely on the thought that a higher API-grade is better than an older one. That is only true on todays, most up-to-date engines.

I can't agree with this. I don't believe that API would spec an oil based soley on the performance of newer engines or engine requirements. I also cannot see specifically mandating fewer ring deposits based on newer engine requirements. I feel that an oil specification must be determined by past perfomance and failures of those parameters, REGARDLESS of how the vehicle has been driven. I also feel that a Northstar engine was a pioneer in engine design, way ahead of its time, and as such placed much greater temperature demands on the oil at the top deck of the piston, and on the compression ring (uppermost) . It is not a coincidence that newer engines should follow that same proven, low emission design.

[Cadillac Jim]

The Porshe 928 and the Infiniti had a 32-valve OHC V8 with DFI on the roads before the Northstar introduction in the 1993 Allante in late 1992. What they didn't have was the combination of durability, emissions, economy, power, and weight of the Northstar. The dry shipping weight of a Nothstar, complete except for cam covers and fuel injection, is 355 pounds according to the shipping invoice of the Jasper that I bought for my car in 2006. You don't see ten-year-old Porshe 928's on the road. Etc. Although versions of the Infiniti and Lexus aluminum 32-valve V8s lasted some years, imitations by Ford and others went out of style, and only the Northstar continues in production, albeit a few generations of designs later, and imitated in design and style in V6's and V8's by most other marques.

But, back to the point, oil is a personal decision, but I see no advantage whatsoever in using high-mileage oil or oil additives in any Northstar, regardless of mileage. The advantages touted in promoting these oils don't apply to the Northstar; they are more attuned to worn pushrod iron V8s with too much piston clearance and oil burning through the rings and valve guides. The Northstar with its steel wet sleeves and direct-acting valve train with controlled oiling system should never have the compression or oil burning characteristics that these oils are designed to address, and their thickening agents could easily be bad for any Northstar. Seal softening additives can be obtained by other means if deemed necessary or appropriate, such as Marvel Mystery Oil or a can of ATF thrown in the mix once a year or so. I wouldn't even do that because it might be bad for the case-half seal.

[Texas Jim]

And I still insist that owners of older Northstar engines don't rely on the thought that a higher API-grade is better than an older one. That is only true on todays, most up-to-date engines.

I can't agree with this. I don't believe that API would spec an oil based soley on the performance of newer engines or engine requirements. I also cannot see specifically mandating fewer ring deposits based on newer engine requirements. I feel that an oil specification must be determined by past perfomance and failures of those parameters, REGARDLESS of how the vehicle has been driven. I also feel that a Northstar engine was a pioneer in engine design, way ahead of its time, and as such placed much greater temperature demands on the oil at the top deck of the piston, and on the compression ring (uppermost) .

It is not a coincidence that newer engines should follow that same proven, low emission design.

JohnnyG,

I am sure you already know this, but just in case...

Your Cadillac V8 qualifies as a ULEV...

Ultra Low Emissions Vehicle...just like some of the hybrids and super economy cars.

[JimD]

....and only the Northstar continues in production....

Not quite.

Just for the record, GM ceased production of the Northstar engine at the end of July, 2010 and scheduled closing of the Livonia, MI powertrain facility soon thereafter.

The Northstar joins a long list of overhead reduction moves including Hummer, Pontiac, Oldsmobile and on and on.

[CarlaValentine]

....and only the Northstar continues in production....

Not quite.

Just for the record, GM ceased production of the Northstar engine at the end of July, 2010 and scheduled closing of the Livonia, MI powertrain facility soon thereafter.

The Northstar joins a long list of overhead reduction moves including Hummer, Pontiac, Oldsmobile and on and on.

I remember seeing an article about the "end of the Northstar". It's really a very sad thing. In my personal opinion, the Northstar was one of the best things GM ever did. I understand the need for overhead reduction, especially in our economy, but I think they could have made a better sacrifice...

[KHE]

The Northstar with its steel wet sleeves

Jim,

The Northstar engine is not a wet sleeve. The coolant does not contact the sleeve. There is a wall of aliminum that surrounds the sleeve and separated it from the water jacket.

The 4.1, 4.5, and 4.9 engines are wet sleeve design.

[Cadillac Jim]

Uh... dry sleeves.