Oil Changing Newbie

[DDLS3]

With few exceptions, mainly operation in extremely cold weather (such as Alaska, far northern MI, upper great plains, Maine or Canada), a better choice is always 10W30 synthetic oil. It has slightly higher viscosity and far less VI improvers. Mobil 1 10W30 is a good product. An ester-based synthetic, such as Red Line, is the best.

Hib,
Thanks, thats the kind of info I was looking for. 49 years in Maine, still have that mind set.

 

[jcs712]

Change the oil when the oil life monitor reads 0%. There is no need to do it sooner, however, if this is a Corvette with a LS1 or LS6, I'd change the oil filter at 50% because the filter used on those engines is so small. Lastly, you're better off using Mobil 1 10W30 rather than 5W30.

I respectfully disagree with some of the information given here. Here are some points I would like to make. Take them for what they are worth.
1. In my opinion, changing the oil before the oil life monitor reads 0 is not a bad thing. Changing the oil more frequently is cheap insurance in my opinion. Yes, it has been documented you could go 10, 15, 20,000 mi on one oil change based on oil analysis but why risk it. Is a $40.00 oil change worth the risk of a damaged or blown engine. The manual also states the oil should be changed no less frequently than once per year. I think the more important thing to look at is the breakdown of the additive packages they put in these oils ie. anti-corrosion inhibitors, acid inhibitors, and anti-foaming agents. I would think the additive package is used up long before the oil looses its lubricating qualities. Does the oil life monitor measure these things; I doubt it.
2. I take issue with the statement that 10W30 is always better than 5w30. This is like saying thicker is always better. Maybe in a racing environment at extremes in temperature, a thicker oil may provide better protection. I would have to see some data to back that up. Most people I know are not racing their cars. If I were to do so, I would consider an enternally mounted oil cooler to handle the extra temp. Both Mobil 1 5w30 and 10w30 are synthetic oils made from the same base stock. Am I missing something here? Aren't both of these oils 30 weight oils at temperature. I think the bigger issue is the oils ability to flow at cold startup since this is when most of the average person's engine wear is going to occur. A 5w30 oil is going to flow better at cold start than a 10w30 oil. I think this is true even at moderate cold temps b/w 0-30 farenheit. Cold startup is where most engine wear is coming into play for the average driver. You fail to mention any warranty issues that may arise from using 10w30 oil when the manufacture recommends 5w30. Should an oil related failure occur, use of 10w30 could present some hurdles to overcome regarding warranty.

I am not discounting information given by Hib, only bring to light some other issues that should be considered on this topic.

 

[Hib Halverson]

[QUOTE='04 Torch Red]=======================================================
Can you please explain VI improvers..thanks[/QUOTE] VI or "viscosity index" improvers are chemicals without lubricity which are added to petroleum or synthesized hydrocarbon base stocks to increase the viscosity range of the oil. For example, without some amount of VI improvers, a 5W30 might end-up a 15W30. VI improvers give the oil a wider viscosity range. Premium, ester-based synthetics have a natural, wide vis. range and seldom, if ever, need VI improvers. For example, Red Line's SAE30 racing oil is actually a 15W30 and it contains no VI improvers.

But...just in case you're getting the idea to use a synthetic race oil on the street, most race oils, including Red Line's contain a lot of EP additives which are great in racing engines but not in street engines because they damage catylitic converters. No matter how good the engine's sealing is, small quanties of oil are burned and go out the exhaust and through the cats. If the oil has a lot of those EP additives, cat life is degraded.

 

[Hib Halverson]

I respectfully disagree with some of the information given here. Here are some points I would like to make. Take them for what they are worth.
(snip)

I am not discounting information given by Hib, only bring to light some other issues that should be considered on this topic.

The disagreement is healthy and the your intent to respectfully disagree is noted.

Nevertheless, what you posted is mostly the typical myth and urban rumor that propagate our hobby and are feed by the marketing of 3000-mile oil changes by the quick lube industsry and the oil refiners. I have ten years worth of data to support not only oil drains at the mfg. recommend interval but even extended drain intervals.

Anyone who really understands high-perfomance engines and lubrication for maximum durability during extreme duty will agree with my believe about 10W30 over any 5W30, including my sources at GM Powertrain, although they can't do it on-the-record because of GM's policy of recommending 5W30 in reponse to pressure from the EPA and the need to meet CAFE.

Your belief that additive packages loose potency before the oil looses it's lubricating properties is misguided. at least in the case of good quality or premium synthetic oils. My last spectrographic analysis of one of the vehicles I have on an engine oil test program showed that at 18,000 miles the additive package was still potent, the wear metals were low but the viscosity had jumped one range from SAE30 to SAE40. Those involved in this test and myself deemed that as unacceptable and set the drain inerval for an ester-based 10W30 in this particular type of engine at 18,000 miles or two years with filter changes every 3000-mi.

You're argument that suggesting that 10W30 is better than 5W30 is faulty because the "thicker is better" belief is a myth, is, itself, faulty. Yes, the idea that thicker is better is faulty if we are comparing 5W30 to a 15W50 or 20W60. In that case, I agree, thicker IS NOT better.

The reason a 10W30 is usually a better choice for a high-performance engine, especially in a severe duty cycle in hot weather is that all the VI improvers in 5W30s cause the oil to thin at high temperatures. Sources in GM Powertrain have agreed with me when it comes to replacing 5W30 with 10W30 in Corvette engines which see track day duty during summer. They recommend not only that, but in the case of C5s and C6es, overfilling the crankcase by a quart.

Here's a test you can perform. Run 20 hot laps on a race track with Mobil 1 5W30 in the car. Run until the oil temp gets up to 275 deg. Record the oil pressure. Change the oil to Red Line 10W30 and run the same 20 laps again. At the end of the test you'll see the oil pressure is higher and the oil temperature is a little lower. Then, ask yourself, "Why is that?"

The "cold start-up" issue is still more urban legend propagated by oil company and oil additive company marketing. The SAE 10W rating means that the oil flows like an SAE10 at 0°C/32°F. A 10 weight oil will flow just fine at 32 and even -10 and, if it's a synthetic it will probably flow just as good at -20 deg. Long before 5W30 oils became widely available in the late 1970s, people used 10W30s in the coldest climates such as Alaska, northern Canada and Maine. If those 10W30s didn't work well, no one could have operated vehicles in those climates before the introduction of 5W30s.

I will agree that for most normal street driving in engines intended to last to GM's durability targets, 5W30 oils are acceptable. It when you get into extreme duty or you want better durability than GM expects, then you need to go to a 10W30.

Bottom line: nothing you've posted has convinced me to change my recomendation that in most cases, a 10W30 is a better choice than 5W30. The only exception would be frequent/continuous operation in very cold weather and, by "very cold" I mean -10 or lower. I've run Red Line 10W30 in -20 weather and oil pressure comes up quickly. Admittedly, Red Line is an ester-based product and ester-based engine oils don't suffer near as much thickening at very low temperatures as do petro-based produdcts, but it worked just fine. I'll admit, however, if I was operating a vehicle on a regular basis in those kinds of temperatures, I'd probably go to a 5W20 or a 5W30, at least during the winter...and if it was an Antarctic winter I'd might even use a 0W20.

But in the case of occasional use in weather that cold, there's going to be no durability problem using 10W30, the Mobil 1 version or the Red Line verison.

You fail to mention any warranty issues that may arise from using 10w30 oil when the manufacture recommends 5w30. Should an oil related failure occur, use of 10w30 could present some hurdles to overcome regarding warranty.

Oh, please....
:nono
...spare me. Now this discussion is just getting silly. Go read a service manual. For Corvette, I have them for 1982-2004. For at least the last 20 years, not only has GM allowed use of 10W30 in lieu of 5W30, it's even recommended in some climates, for some duty cycles and is even required in some instances, such as 90-92 LT5s.

With all due respect, my suggestion is: stop believing the typical myths/urban legends about engine oils and do some research to learn the truth.

 

['04 Torch Red]

VI or "viscosity index" improvers are chemicals without lubricity which are added to petroleum or synthesized hydrocarbon base stocks to increase the viscosity range of the oil. For example, without some amount of VI improvers, a 5W30 might end-up a 15W30. VI improvers give the oil a wider viscosity range. Premium, ester-based synthetics have a natural, wide vis. range and seldom, if ever, need VI improvers. For example, Red Line's SAE30 racing oil is actually a 15W30 and it contains no VI improvers.

But...just in case you're getting the idea to use a synthetic race oil on the street, most race oils, including Red Line's contain a lot of EP additives which are great in racing engines but not in street engines because they damage catylitic converters. No matter how good the engine's sealing is, small quanties of oil are burned and go out the exhaust and through the cats. If the oil has a lot of those EP additives, cat life is degraded.

Thanks Hib!

 

['04 Torch Red]

The disagreement is healthy and the your intent to respectfully disagree is noted.

Nevertheless, what you posted is mostly the typical myth and urban rumor that propagate our hobby and are feed by the marketing of 3000-mile oil changes by the quick lube industsry and the oil refiners. I have ten years worth of data to support not only oil drains at the mfg. recommend interval but even extended drain intervals.

Anyone who really understands high-perfomance engines and lubrication for maximum durability during extreme duty will agree with my believe about 10W30 over any 5W30, including my sources at GM Powertrain, although they can't do it on-the-record because of GM's policy of recommending 5W30 in reponse to pressure from the EPA and the need to meet CAFE.

Your belief that additive packages loose potency before the oil looses it's lubricating properties is misguided. at least in the case of good quality or premium synthetic oils. My last spectrographic analysis of one of the vehicles I have on an engine oil test program showed that at 18,000 miles the additive package was still potent, the wear metals were low but the viscosity had jumped one range from SAE30 to SAE40. Those involved in this test and myself deemed that as unacceptable and set the drain inerval for an ester-based 10W30 in this particular type of engine at 18,000 miles or two years with filter changes every 3000-mi.

You're argument that suggesting that 10W30 is better than 5W30 is faulty because the "thicker is better" belief is a myth, is, itself, faulty. Yes, the idea that thicker is better is faulty if we are comparing 5W30 to a 15W50 or 20W60. In that case, I agree, thicker IS NOT better.

The reason a 10W30 is usually a better choice for a high-performance engine, especially in a severe duty cycle in hot weather is that all the VI improvers in 5W30s cause the oil to thin at high temperatures. Sources in GM Powertrain have agreed with me when it comes to replacing 5W30 with 10W30 in Corvette engines which see track day duty during summer. They recommend not only that, but in the case of C5s and C6es, overfilling the crankcase by a quart.

Here's a test you can perform. Run 20 hot laps on a race track with Mobil 1 5W30 in the car. Run until the oil temp gets up to 275 deg. Record the oil pressure. Change the oil to Red Line 10W30 and run the same 20 laps again. At the end of the test you'll see the oil pressure is higher and the oil temperature is a little lower. Then, ask yourself, "Why is that?"

The "cold start-up" issue is still more urban legend propagated by oil company and oil additive company marketing. The SAE 10W rating means that the oil flows like an SAE10 at 0°C/32°F. A 10 weight oil will flow just fine at 32 and even -10 and, if it's a synthetic it will probably flow just as good at -20 deg. Long before 5W30 oils became widely available in the late 1970s, people used 10W30s in the coldest climates such as Alaska, northern Canada and Maine. If those 10W30s didn't work well, no one could have operated vehicles in those climates before the introduction of 5W30s.

I will agree that for most normal street driving in engines intended to last to GM's durability targets, 5W30 oils are acceptable. It when you get into extreme duty or you want better durability than GM expects, then you need to go to a 10W30.

Bottom line: nothing you've posted has convinced me to change my recomendation that in most cases, a 10W30 is a better choice than 5W30. The only exception would be frequent/continuous operation in very cold weather and, by "very cold" I mean -10 or lower. I've run Red Line 10W30 in -20 weather and oil pressure comes up quickly. Admittedly, Red Line is an ester-based product and ester-based engine oils don't suffer near as much thickening at very low temperatures as do petro-based produdcts, but it worked just fine. I'll admit, however, if I was operating a vehicle on a regular basis in those kinds of temperatures, I'd probably go to a 5W20 or a 5W30, at least during the winter...and if it was an Antarctic winter I'd might even use a 0W20.

But in the case of occasional use in weather that cold, there's going to be no durability problem using 10W30, the Mobil 1 version or the Red Line verison.

Oh, please....
:nono
...spare me. Now this discussion is just getting silly. Go read a service manual. For Corvette, I have them for 1982-2004. For at least the last 20 years, not only has GM allowed use of 10W30 in lieu of 5W30, it's even recommended in some climates, for some duty cycles and is even required in some instances, such as 90-92 LT5s.

With all due respect, my suggestion is: stop believing the typical myths/urban legends about engine oils and do some research to learn the truth.

:L Hib crushes the guys nerts...

 

[jwawhite]

Some comments!

Thanks for responding to my original question about being an oil changing newbie.

I've changed oil and filters before but not on a Corvette.

How about some basics, I haven't looked yet but where is the oil filter? Is it readily accessible from the top of the engine compartment? What is the torque on the drain bolt? Where is a good place to buy a magnetic plug?

I will be switching to Redline--(thanks for the info Hib!), where is a good place to buy it? I've always just bought a case of Castrol 20/50...on my other cars.

Dealerships.. I'd rather just do the work myself, I'm never satisfied... car is rifled through, dirt on the wheel, some rap on the radio, the seats been changed. When I worked at a GM Dealership years and years ago I was told never to fiddle with the radio, seat, etc.

 

[DDLS3]

The oil filter is accessable from the underside. You should be able to find a magnetic drain plug at NAPA, Advance, Autozone, or any other major parts store. You could also order from Jegs or Summit if by chance it is not available in your area. Drain plug torque 18 ftlbs.

 

[jcs712]

The disagreement is healthy and the your intent to respectfully disagree is noted.

Nevertheless, what you posted is mostly the typical myth and urban rumor that propagate our hobby and are feed by the marketing of 3000-mile oil changes by the quick lube industsry and the oil refiners. I have ten years worth of data to support not only oil drains at the mfg. recommend interval but even extended drain intervals.

Anyone who really understands high-perfomance engines and lubrication for maximum durability during extreme duty will agree with my believe about 10W30 over any 5W30, including my sources at GM Powertrain, although they can't do it on-the-record because of GM's policy of recommending 5W30 in reponse to pressure from the EPA and the need to meet CAFE.

Your belief that additive packages loose potency before the oil looses it's lubricating properties is misguided. at least in the case of good quality or premium synthetic oils. My last spectrographic analysis of one of the vehicles I have on an engine oil test program showed that at 18,000 miles the additive package was still potent, the wear metals were low but the viscosity had jumped one range from SAE30 to SAE40. Those involved in this test and myself deemed that as unacceptable and set the drain inerval for an ester-based 10W30 in this particular type of engine at 18,000 miles or two years with filter changes every 3000-mi.

You're argument that suggesting that 10W30 is better than 5W30 is faulty because the "thicker is better" belief is a myth, is, itself, faulty. Yes, the idea that thicker is better is faulty if we are comparing 5W30 to a 15W50 or 20W60. In that case, I agree, thicker IS NOT better.

The reason a 10W30 is usually a better choice for a high-performance engine, especially in a severe duty cycle in hot weather is that all the VI improvers in 5W30s cause the oil to thin at high temperatures. Sources in GM Powertrain have agreed with me when it comes to replacing 5W30 with 10W30 in Corvette engines which see track day duty during summer. They recommend not only that, but in the case of C5s and C6es, overfilling the crankcase by a quart.

Here's a test you can perform. Run 20 hot laps on a race track with Mobil 1 5W30 in the car. Run until the oil temp gets up to 275 deg. Record the oil pressure. Change the oil to Red Line 10W30 and run the same 20 laps again. At the end of the test you'll see the oil pressure is higher and the oil temperature is a little lower. Then, ask yourself, "Why is that?"

The "cold start-up" issue is still more urban legend propagated by oil company and oil additive company marketing. The SAE 10W rating means that the oil flows like an SAE10 at 0°C/32°F. A 10 weight oil will flow just fine at 32 and even -10 and, if it's a synthetic it will probably flow just as good at -20 deg. Long before 5W30 oils became widely available in the late 1970s, people used 10W30s in the coldest climates such as Alaska, northern Canada and Maine. If those 10W30s didn't work well, no one could have operated vehicles in those climates before the introduction of 5W30s.

I will agree that for most normal street driving in engines intended to last to GM's durability targets, 5W30 oils are acceptable. It when you get into extreme duty or you want better durability than GM expects, then you need to go to a 10W30.

Bottom line: nothing you've posted has convinced me to change my recomendation that in most cases, a 10W30 is a better choice than 5W30. The only exception would be frequent/continuous operation in very cold weather and, by "very cold" I mean -10 or lower. I've run Red Line 10W30 in -20 weather and oil pressure comes up quickly. Admittedly, Red Line is an ester-based product and ester-based engine oils don't suffer near as much thickening at very low temperatures as do petro-based produdcts, but it worked just fine. I'll admit, however, if I was operating a vehicle on a regular basis in those kinds of temperatures, I'd probably go to a 5W20 or a 5W30, at least during the winter...and if it was an Antarctic winter I'd might even use a 0W20.

But in the case of occasional use in weather that cold, there's going to be no durability problem using 10W30, the Mobil 1 version or the Red Line verison.

Oh, please....
:nono
...spare me. Now this discussion is just getting silly. Go read a service manual. For Corvette, I have them for 1982-2004. For at least the last 20 years, not only has GM allowed use of 10W30 in lieu of 5W30, it's even recommended in some climates, for some duty cycles and is even required in some instances, such as 90-92 LT5s.

With all due respect, my suggestion is: stop believing the typical myths/urban legends about engine oils and do some research to learn the truth.

Hib:

Thanks for addressing my points in your response. I take no offense in what you have written. These types of discussions are healthly and I hope the forum users can benefit for our discussion. My comment on the warranty was a bit premature. I do understand that most manufacturers will allow different viscosity ratings to be used for different operating temperature ranges. I am sure 10W30 synthetic will not cause any harm and may even be advantageious in certain operating conditions. I respect your experience in these matters and appreciate you allowing me to learn something new.

You refer to the Red Line oils several times in your posts. Do you recommend this over the Mobil 1 product?

As for the guy who thinks these discussions are about crushing/flamming somebody for speaking out, that is not what this site is all about. Too often, people believe something has to be true simply becuase they read it on the internet.

 

[Hib Halverson]

Thanks for responding to my original question about being an oil changing newbie.

I've changed oil and filters before but not on a Corvette.

How about some basics, I haven't looked yet but where is the oil filter? Is it readily accessible from the top of the engine compartment? What is the torque on the drain bolt? Where is a good place to buy a magnetic plug?

I will be switching to Redline--(thanks for the info Hib!), where is a good place to buy it? I've always just bought a case of Castrol 20/50...on my other cars.

Dealerships.. I'd rather just do the work myself, I'm never satisfied... car is rifled through, dirt on the wheel, some rap on the radio, the seats been changed. When I worked at a GM Dealership years and years ago I was told never to fiddle with the radio, seat, etc.

With the exception of the 90-95 LT5, starting with 1957, all Corvette oil filters are on the bottom of the engine, next to the oil pan. 57-67 uses the PF141, 68-91, uses the PF1218, 92-96 uses the PF52 and 97-04 uses the PF46. The 05 may use the PF46, too, but I'm not 100% sure on that.

Unfortunately, Red Line is sometimes hard to find at the retail level. There are some mail order places that sell it (Summit, Racer Wholesale, etc). One thing you can do is call Red Line (800 624 7958) and ask for a list of dealers in your area. Also, I've hread that in some circumstances (such as someone who calls and pleas with them a little) Red Line will sell direct and take the order on the phone.

If this car you are working on is anything close to late model, I'd not recommend a 20W50 unless the duty cycle is exclusively road racing in very hot weather and the engine has no oil cooler.

 

[Hib Halverson]

Hib:
(snip)
My comment on the warranty was a bit premature. I do understand that most manufacturers will allow different viscosity ratings to be used for different operating temperature ranges.

My reply was specific to warranty requirements GM sets for Corvettes as far as the engine oil viscosities recommended and allowed. I am not well-versed on what standards manufacturers other then GM set for engine oil, other than knowing that in some cases of very late model vehicles, Ford specifices some 5W20 oils.

(snip) I respect your experience in these matters and appreciate you allowing me to learn
something new.

Glad to be of service

You refer to the Red Line oils several times in your posts. Do you recommend this over the Mobil 1 product?

Well....here's the gray-area answer. If we are talking about the ultimate in lubrication in high-load, high oil temperature applications, Red Line, because of its ester base stock, is a better choice than Mobil 1 which is a synthesized hydrocarbon product. The downside of RL for some is its high cost in comparison to Mobil 1. In my own cars, I offset that by using extended drain intervals on vehicles which see 10,000 miles a year or more.

I'd say that if the duty cycle was high-peformance street use with occasional racing, such as autocross or "light" track day use, then Mobil1 10W30 is just fine. On the other hand, if the car sees that kind of duty in very hot weather or duty that is more severe, such as frequent road racing, then the Red Line 10W30 is better...and if the engine has no cats I'd use Red Line SAE30 Race Oil which also meets the 15W30 specification.

That said, few people operate their cars in duty cycles that are truly high-load/high-oil-temp. on a regular basis, so they may not really need Red Line. In short, Mobil 1 is a good synthetic oli, but Red Line is the best. Economics may force one to accept "good" in lieu of "best" and, as long as the duty-cycle is not "over-the-top" in its severity, Mobil 1 will provide excellent protection and durability.

What the consumer needs to avoid are oils which are not true synthetics, such as any oil labeled "semi-synthetic", "synthetic blend", or "blended synthetic". Also, Castrol Syntec, while meeting the legal "letter of the law" as to what constitutes a synthetic oil, is really not a synthetic when judged the way chemists or petro-chemical engineers benchmark oils.

Hope this helps.
Have a great week, everybody.

 

[AZMike]

OK - a question for you Hib - I live here in Phoenix and regularly see temps of 110+ in the sumertime. For that reason, I run Mobile1 10w30 in the Vette to help out with the heat.

I also have a 73 Ford Brnco that I do a lot of slow speed crawling and such in - it regularly sees coolant temps of 230+. I run 10w40 (non-synthetic) there to help deal with the heat issue - I have no external oil cooler. I've always been told that higher weight oils are better in the heat as a general rule. Is this true, or is this one of those myths that are just out there?

Just wanted to know - I've found your posts very education about oil - which is something most people give little thought to.

 

[Hib Halverson]

OK - a question for you Hib - I live here in Phoenix and regularly see temps of 110+ in the sumertime. For that reason, I run Mobile1 10w30 in the Vette to help out with the heat.

I also have a 73 Ford Brnco that I do a lot of slow speed crawling and such in - it regularly sees coolant temps of 230+. I run 10w40 (non-synthetic) there to help deal with the heat issue - I have no external oil cooler. I've always been told that higher weight oils are better in the heat as a general rule. Is this true, or is this one of those myths that are just out there?

Just wanted to know - I've found your posts very education about oil - which is something most people give little thought to.

Certainly, heavy off-road use presents a difference set of circumstances, especially for cooling because you sometimes running the vehicle in low range, low gears, moderate load but little vehicle speed.

I've got a 99 Blazer with the HD off-road equip. package, ZR-2 and I do a bit of off road stuff myself. The Blazer came with a factory engine oil cooler and HD cooling plus I added a lower temp t'stat and Red Line Water Wetter so I seldom see over 200.

Higher weight oils are necessary when oil temperature gets really high (250 or higher for petro-based oil or 275 or higher with Mobil 1) and the engine is seeing high loads. You're probably just fine with the 10W40. In fact, unless you're seeing very high oil temp in that engine, a 10W30 is ok, too. Your coolant temp runs a bit high, but not unreasonable. One thing you can do is reduce the percentage of antifreeze and add Red Line Water Wetter. That might give you 5-10 deg. lower temp.

 

[hoosierdaddy]

Are the jacking points on a C-5 pretty visible and easy to find? Do you jack it all off the ground with four jack stands or what to change the oil?

Thanks,
Bill

 

[JR_Vette]

For those of you changing your oil at 50% oil life, you are wasting your money. If you doubt me, take a sample of your oil and have it tested. It's cheap ($20) to do and worth it. I think you will then see you are wasting your money. Here are several oil tests, the first one is Mobil 1, the second is Amsoil. Both oils live well beyond 3K, 5K and 7K miles. Of course driving habits, temp, environment all play a part in oil wear.

And for you 3K mile changers a quote from the Mobil 1 test :

"While the wear metals all accumulated steadily over the course of the test, the highest concentrations of accumulation per mile occurred in the first 3,000 miles of the test! From the 3,000-mile mark all the way to 18,000 miles, only lead showed an increase in per-mile wear beyond 3,000 miles."

Draw you're own conclusion, but me thinks the most wear happens during the first 3,000 miles of a oil change. The test results were the same for Amsoil...immediate accumulation of metals in the first 3K miles.
http://neptune.spacebears.com/cars/stories/mobil1.html
http://neptune.spacebears.com/cars/stories/oil-life.html

Here's a good forum for oil tests :
http://theoildrop.server101.com/ubb/ultimatebb.php?ubb=forum;f=3

If you want to have your oil tested :
http://www.blackstone-labs.com/auto.html

 

[COR4VETTE]

C5 Oil Change Procedures

IMPORTANT: In order to completely drain the oil from the pan internal baffling, the bottom of the oil pan must be level from side to side and slightly leaned forward during oil drain procedure. Allow a MINIMUM of 7 minutes for the engine oil to fully drain, once the engine oil drain plug and the engine oil filter are removed.

1) Remove the engine oil drain plug and allow oil to drain.
2) Remove the engine oil filter and allow any remaining oil to drain.
3) Fill new oil filter with some of the new oil and oil the new oil filter gasket.
4) Install new oil filter, tighten to 22 foot-pounds (30 Newton-meters). (this will seem very tight)
5) Reinstall oil drain plug and tighten to 18 foot-pounds (25 Newton-meters).
6) Put the new oil in. (use Mobil 1, 5W30 (6.0 to 6.5 quarts))
7) Wait a MINIMUM of 3 minutes for the new oil to fully fill the engine oil pan internal baffling.
8) Run the engine for 3 minutes and thoroughly inspect the oil filter and drain plug for leaks.
9) Allow engine to cool for a minimum of 3 minutes.
10) Check engine oil level.
11) Top-off the engine oil to full mark on DIP STICK. (if needed)

 

[DDLS3]

Provided the oil sample grab proceedure is correct, the results are very reliable and enlightening. I have sampled large engines, turbines, and gearboxes in the power plant for nearly 20 years. Many of the synthetic lubes go 3 and 4 times longer between changes than conventional wisdom has trained us to believe.

 

['04 Torch Red]

C5 Oil Change Procedures

IMPORTANT: In order to completely drain the oil from the pan internal baffling, the bottom of the oil pan must be level from side to side and slightly leaned forward during oil drain procedure. Allow a MINIMUM of 7 minutes for the engine oil to fully drain, once the engine oil drain plug and the engine oil filter are removed.

1) Remove the engine oil drain plug and allow oil to drain.
2) Remove the engine oil filter and allow any remaining oil to drain.
3) Fill new oil filter with some of the new oil and oil the new oil filter gasket.
4) Install new oil filter, tighten to 22 foot-pounds (30 Newton-meters). (this will seem very tight)
5) Reinstall oil drain plug and tighten to 18 foot-pounds (25 Newton-meters).
6) Put the new oil in. (use Mobil 1, 5W30 (6.0 to 6.5 quarts))
7) Wait a MINIMUM of 3 minutes for the new oil to fully fill the engine oil pan internal baffling.
8) Run the engine for 3 minutes and thoroughly inspect the oil filter and drain plug for leaks.
9) Allow engine to cool for a minimum of 3 minutes.
10) Check engine oil level.
11) Top-off the engine oil to full mark on DIP STICK. (if needed)

6)10W30 Mobil 1

 

[RodsnRides]

Antarctica?!

I'll admit, however, if I was operating a vehicle on a regular basis in those kinds of temperatures, I'd probably go to a 5W20 or a 5W30, at least during the winter...and if it was an Antarctic winter I'd might even use a 0W20.

Hi folks, boy howdy did I pick up on this one. Because I am typing this from McMurdo Station, Antarctica! This is my twelfth trip to the last continent. More info about our program can be seen at www.polar.org. I have some information about what WE use.

Our light vehicle fleet is F-350 Ford pickups and 4X4 vans (Ford?! Yeah-low bidder!), running Triton 5.4L V-8s and AOD autos. Our ambient temperatures range from about -40 F in August to about +40 F in December (warmest month).

The engine oil of choice in this application is Union 76 synthetic HD Arctic 0w-30. This oil meets API service CH-4, CG-4, CF-4, and CFSJ. I know, MOST folks won't use this product, but Alaska, North Dakota, Minnesota, etc. may be interested, although they also probably don't drive a modern Corvette in January-but maybe their daily driver or pickup truck. This is all just for your interest and to let you know that this is one Corvette enthusiast that also goes far South for the winter (well, coupla months, anyway).

Hence MY question: I have been running Castrol GTX 20w-50 during the summer months in Colorado-May to September or so. I run GTX 10w-30 the rest of the time. I change oil and filter every 3K miles or at least annually, depending on frequency of use (daily driver versus recreational-we have several vehicles for differing uses). Am I doing the right thing? Is 20w-50 right or wrong? Other than the '98 Silverado Z-71 (always 5w-30), everything else is '70-'72 small block Chevy (one Pontiac 400-'67 GTO).

I would greatly appreciate Mr. Halverson's and others input on the matter. Thank you.

Rick

 

[JR_Vette]

Hence MY question: I have been running Castrol GTX 20w-50 during the summer months in Colorado-May to September or so. I run GTX 10w-30 the rest of the time. I change oil and filter every 3K miles or at least annually, depending on frequency of use (daily driver versus recreational-we have several vehicles for differing uses). Am I doing the right thing? Is 20w-50 right or wrong? Other than the '98 Silverado Z-71 (always 5w-30), everything else is '70-'72 small block Chevy (one Pontiac 400-'67 GTO).

I would greatly appreciate Mr. Halverson's and others input on the matter. Thank you.

Rick

20W-50? Unless you're racing and/or having oil burning issue I would think this is overkill. When I had my 69 Camaro I ran Castrol also, but I used 10W-30. In my opinion, unless you're driving in the desert, 20W-50 is too thick. If it were me, I would use 10W-30 year round, and just watch the oil level.

Let's see what Hib and the others have to say.