oil change question
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Heel & Toe
Joined: Aug 2004
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From: florida
oil change question
Hello, I was wondering how many of you are familiar with synthetic oil properties? Specificly Mobil1. I have a DD now so my 04' MSG does'nt travel much. My stealership is sending me threatening letters regarding my car being overdue for an oil change. The car reads 47% oil life remaining. Does the General support that reading as a guide for oil changes? If synthetic oil is so great would there be a time limit on its life as opposed to a milage reading? I don't want my factory warranty to become void. Thanks!
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If it is anything like most dealers, they send these form letters out based on the traditional 3 month, 3000 miles standard for conventional oil changes. With the synthetics, you do not have to change it that often unless you want to. I normally wait until my oil life shows about 40-45% on the DIC, then I change mine. That comes out to be about 4500 miles.
Team Owner
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From: Oklahoma City OK
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Originally Posted by mikestuff
Check the owner's manual maintenance schedule to see what you have to do to maintain the warranty.
Team Owner
Joined: Jul 2004
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From: NJ
St. Jude Donor '05-'08
I would change at 5K unless I travelled less than that per year. I change my oil before the winter and then again in the spring. I really don't look at mileage as much as I look at time it has been sitting in the car (I put on about 8K per year).
My car sits all winter in the garage so I feel that fresh oil is best to eliminate the chance of any breakdown. In the spring I run the old oil for a bit, but then change it towards the later part so there is fresh oil for the summer.
Regarding your letters - I believe they are just notification letters. If they are not paying for the oil change then you can go anywhere and they would still send you letters. Of course I would verify with your warranty book to see if there are any guidelines that must be followed in order not to void it. If there are then I would save all receipts stating when you had the oil changed...
My car sits all winter in the garage so I feel that fresh oil is best to eliminate the chance of any breakdown. In the spring I run the old oil for a bit, but then change it towards the later part so there is fresh oil for the summer.
Regarding your letters - I believe they are just notification letters. If they are not paying for the oil change then you can go anywhere and they would still send you letters. Of course I would verify with your warranty book to see if there are any guidelines that must be followed in order not to void it. If there are then I would save all receipts stating when you had the oil changed...
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Joined: Dec 2000
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From: San Diego CA
Go by the D.I.C. or 12 months, whichever occurs first.The Mobil 1 that is used in many C5s has been proven to last 12,000 miles with no filter change (although 2-3 quarts were added during this time interval), so I would not worry about going more than 5000 miles as long as you follow the rule listed above.
I change my oil once per year.
I change my oil once per year.
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Team Owner
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From: Houston,Texas USA
My first oil change was at 2,800 miles, the DIC showed 81%. The second oil change was at 5,100 miles, and the DIC showed 77%. I plan on changing the oil on this car every 2,500 miles. All my other cars go 2,000 miles between changes. To me, it's cheap insurance.
Drifting
Joined: May 2000
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From: Southern NH
Originally Posted by Dave68
Go by the D.I.C. or 12 months, whichever occurs first.The Mobil 1 that is used in many C5s has been proven to last 12,000 miles with no filter change (although 2-3 quarts were added during this time interval), so I would not worry about going more than 5000 miles as long as you follow the rule listed above.
I change my oil once per year.
I change my oil once per year.
The DIC oil life algorithm is somewhat conservative (except for dusty conditions). As per the manual, DIC or 12 months.
Safety Car
Joined: Dec 2002
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From: SE Idaho
St. Jude Contributor
Originally Posted by LH04
Hello, I was wondering how many of you are familiar with synthetic oil properties? Specificly Mobil1. I have a DD now so my 04' MSG does'nt travel much. My stealership is sending me threatening letters regarding my car being overdue for an oil change. The car reads 47% oil life remaining. Does the General support that reading as a guide for oil changes? If synthetic oil is so great would there be a time limit on its life as opposed to a milage reading? I don't want my factory warranty to become void. Thanks!
GM wants you to follow the oil life gage in the car, except for the one-year change if the car is not driven that much. The gage is more accurate than most people believe, but I have seen the testing documentation on the use of the gage or an oil change light, and it is quite impressive.
I have had two oil analysis performed on my Mobil 1. First oil change was done at 5800+ miles and the oil was in excellent condition. Second oil change was done with 6200+ miles on the oil, and the oil was in very good condition. The TBN was still high on both of the reports. If you are running a K&N or similar type filter, you might want to change around 20 percent due to the increased amount of dirt a K&N type filter allows into the engine. However, if running a paper filter, go for about 10 percent.
Dealers and oil change places are in the business to change oil and make money.
Last edited by WhiteC5Vette; Dec 9, 2004 at 06:28 PM.
Melting Slicks
Joined: Nov 2003
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From: Atlanta GA
the Mobile1 with the K&N filter is proven to run 20,000 miles without any problems at all. Infact, i saw a review where they changed the oil on a regular car every 3,000 miles, and then with the synthetic oil and special filter, the one oil change at 20,000 miles did less wear to the engine than changing a regualr cars oil every 3,000 miles.
I drive my vette all the time, I run Mobile1 with the K&N, changed the oil at 9,000 - 10,000 mile mark, oil looked (golden) brown (still not totally black), and I didnt burn more than half a quart, with no need to refill inbetween. I know many of you guys might say that the oil looses its viscosity/strenght even though it looks nice...but they run that oil to 30,000 miles on test cars before signs of wear in the oil itself become bad.
just my .02
red
I drive my vette all the time, I run Mobile1 with the K&N, changed the oil at 9,000 - 10,000 mile mark, oil looked (golden) brown (still not totally black), and I didnt burn more than half a quart, with no need to refill inbetween. I know many of you guys might say that the oil looses its viscosity/strenght even though it looks nice...but they run that oil to 30,000 miles on test cars before signs of wear in the oil itself become bad.
just my .02
red
Tech Contributor
Joined: Oct 1999
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From: Charlotte, NC (formerly Endicott, NY)
Originally Posted by Tom/99
To me, it's cheap insurance.
Sometimes you just do not need to do some things.
I run my car in several DEs per year and put about 4K miles on per year. I change the oil once per year. I just changed it last week which was one year to the day from the previous time and the oil life indicator was at 15%.
Bill
Burning Brakes
Joined: Feb 2002
Posts: 801
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From: Ashburn VA
Originally Posted by red97vette
the Mobile1 with the K&N filter is proven to run 20,000 miles without any problems at all. Infact, i saw a review where they changed the oil on a regular car every 3,000 miles, and then with the synthetic oil and special filter, the one oil change at 20,000 miles did less wear to the engine than changing a regualr cars oil every 3,000 miles.
I drive my vette all the time, I run Mobile1 with the K&N, changed the oil at 9,000 - 10,000 mile mark, oil looked (golden) brown (still not totally black), and I didnt burn more than half a quart, with no need to refill inbetween. I know many of you guys might say that the oil looses its viscosity/strenght even though it looks nice...but they run that oil to 30,000 miles on test cars before signs of wear in the oil itself become bad.
just my .02
red
I drive my vette all the time, I run Mobile1 with the K&N, changed the oil at 9,000 - 10,000 mile mark, oil looked (golden) brown (still not totally black), and I didnt burn more than half a quart, with no need to refill inbetween. I know many of you guys might say that the oil looses its viscosity/strenght even though it looks nice...but they run that oil to 30,000 miles on test cars before signs of wear in the oil itself become bad.
just my .02
red
Mines not a daily drive so I stick to the 12 month rule. I never even get close to 0% on the DIC.
Racer
Joined: Oct 2004
Posts: 366
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From: Sunnyvale CA
Most of the synthetic oil mfrs including the high end guys (Redline, Amsoil, etc.) recommend at least changing the oil once a year. I'm sure you could go longer but then you really should go on a sampling/analysis program to establish the integrity of the oil as a function of time. I'm guessing two years wouldn't be out of the question. Depends a lot on what the miles were like. If the few miles you did drive during the time interval were freeway miles where the oil came up to full temperature and had a chance to boil off moisture and volatiles then ok. If it was short trips to the store then I would stick with once a year.
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Joined: Oct 2004
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From: Manassas Park VA
St. Jude Donor '07-'08,-'13-'14, '16-'17
I change mine when ever I need a few hours away from the wife and kids 
It's worth the $40 for the few hours of piece and quite.
Peace
Willfulone
It's worth the $40 for the few hours of piece and quite.Peace
Willfulone
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From: Mustang OK
Follow your owner's manual and forget the dealership. Everything will be fine. Change engine oil and filter as indicated by the Engine Oil Life System or every 12 months, whichever occurs first. The GM Service Manual reads much the same.
