frequency of oil changes
Racer
Joined: Aug 2010
Posts: 472
Likes: 9
From: San Diego CA
Just to add to the conversation, how many of you have drilled additional holes in your dip stick? I just did this and boy, what a difference that makes. I now have four holes and it reads much more consistently. I wish I would have done this long ago.
For those of you who want to do this I used a Cobalt drill bit and had to drill very very slow. I think it's stainless steel.
For those of you who want to do this I used a Cobalt drill bit and had to drill very very slow. I think it's stainless steel.
Race Director
Joined: Sep 2004
Posts: 11,874
Likes: 263
From: Arlington Va Current ride 04 vert, previous vettes: 69 vert, 77 resto mod
so you are saying the holes make it easy to see the fluid level since the oil will bridge the gap of the hole and fill it showing the fluid level?
Drifting
Joined: Sep 2012
Posts: 1,665
Likes: 789
From: Hernando MS
I re-use my own Mobil 1. I change both my corvette's oil once a year, they usually see less than 5,000 combined per/yr. So I save the oil and use it in my work van that'll easily get 3 changes a year. Over 250,000 miles in the van and it hasn't complained yet.
Last edited by MikeG37; Jun 7, 2018 at 01:30 AM.
Safety Car
Joined: Jan 2004
Posts: 4,549
Likes: 343
From: Glastonbury CT
In the 2000 i met an engineer from Mobil 1. He said they tested a small block 350 and only changed the filter every 10,000 miles and ran the same oil for 250,000 miles and never had a problem. He showed me the motor and i to recycle my used oil for my other vehicles. (Ford)
Le Mans Master
Joined: Sep 2003
Posts: 8,812
Likes: 2,029
From: eastern NC
Synthetic Oil: Rx for Long Engine Life
Since this topic comes up from time to time, and I haven't seen appear in a few years, I thought I'd bring it up now. This article, Synthetic Oil: Rx for Long Engine Life, originally created from a book by Curt Scott, is an excellent tutorial on the many benefits of using synthetic oils. It was compiled in 1986, and while much has transpired with synthetics since then, it makes for a great tutorial for those that may not yet appreciate the real benefits of synthetics. You can go here to find a full copy of the article.
The article includes many anecdotal stories and experiences of the author related to the use of synthetics. One of my favorite stories is one related to a test sponsored by AmsOil (an early manufacturer of synthetic oil products) on a New York City taxi fleet. You may also find it interesting. Since it was sponsored by AmsOil, you can expect some salesmanship, but the outcome speaks for itself.
Good luck... GUSTO
The article includes many anecdotal stories and experiences of the author related to the use of synthetics. One of my favorite stories is one related to a test sponsored by AmsOil (an early manufacturer of synthetic oil products) on a New York City taxi fleet. You may also find it interesting. Since it was sponsored by AmsOil, you can expect some salesmanship, but the outcome speaks for itself.
This demonstration involved the use of its 100% synthetic engine oils in a New York City taxi fleet. The test, sponsored and supervised by a major lubricant additive manufacturer, compared the overall performance capabilities of Amsoil's 10W-40 synthetic oil with a number of leading petroleum motor oils. The demonstration was scheduled to encompass 60,000 miles of New York taxi service on each car. With the high levels of idling time typically encountered in such service, the total number of "engine miles" of each car was estimated to be about double the miles registered on its odometer.
Initially the demonstration was to have required that each taxi, equipped with a Chevrolet 229 CID V6 engine, have its oil and filter changed every 3,000 miles. But Amsoil insisted that an alteration of the test procedure be instituted. The company's intent was to push its synthetic oil to the extreme and evaluate how it compared to the petroleum oils drained at the originally-specified, 3,000 mile intervals. The twelve Amsoil-lubricated vehicles were thus divided into three groups of four taxis each. Group 1 (Amsoil) would double the control interval, with oil and filter drain at 6,000 miles; Group 2 (Amsoil) would quadruple the control interval, with oil and filter drain at 12,000 miles; and Group 3 (Amsoil) would not change the oil *for the duration of the test*; thus multiplying the (petroleum) Control Group's drain-control interval by twenty times. In place of changing the oil, these (Group 3) cars would be equipped with Amsoil's ByPass oil filter, claimed by the company to keep (synthetic) oil analytically clean for up to 25,000 miles of driving, without replacing the element. The by-pass filter element was changed at 12,500 mile intervals for the duration of the test.
Following the year-long demonstration, each of the engines was disassembled, both to determine the levels of sludge, varnish, and rust that had accumulated inside the engine, and to carefully measure the amounts of wear experienced on critical engine components. Pictured on the previous page are representative samples of various components of the test engines. In the first example, the pistons and intake valves of the petroleum Control Group (*oil and filter changes every 3,000 miles*), are illustrated. The lower set of photos represent the same engine components from an Amsoil Group 3 vehicle. Note the substantially reduced varnish and sludge deposits on the synthetic-oil lubricated components, and the remarkably good overall condition of the Amsoil Group 3 piston rings and valves.
To summarize the findings and conclusions, the test facility responsible for the demonstration submitted this statement: "The data presented in this report indicates that the Amsoil synthetic SAE 10W-40 passenger-car motor oil formulation...provided protection of the test engines from excessive wear and deposit formation, far beyond the normal 3,000-mile change interval." In fact, the level of protection was such that those engines in which the original synthetic oil was run for the entire duration of the (60,000-mile) test showed less wear than did the Control Group vehicles using premium, 10W-40 petroleum oil and 3,000-mile drain intervals.
The above linked article has photos that go with this story as well. By the way, growing up with a mechanic for a Dad, I can well remember his insisting on those 3,000 mile oil changes... Initially the demonstration was to have required that each taxi, equipped with a Chevrolet 229 CID V6 engine, have its oil and filter changed every 3,000 miles. But Amsoil insisted that an alteration of the test procedure be instituted. The company's intent was to push its synthetic oil to the extreme and evaluate how it compared to the petroleum oils drained at the originally-specified, 3,000 mile intervals. The twelve Amsoil-lubricated vehicles were thus divided into three groups of four taxis each. Group 1 (Amsoil) would double the control interval, with oil and filter drain at 6,000 miles; Group 2 (Amsoil) would quadruple the control interval, with oil and filter drain at 12,000 miles; and Group 3 (Amsoil) would not change the oil *for the duration of the test*; thus multiplying the (petroleum) Control Group's drain-control interval by twenty times. In place of changing the oil, these (Group 3) cars would be equipped with Amsoil's ByPass oil filter, claimed by the company to keep (synthetic) oil analytically clean for up to 25,000 miles of driving, without replacing the element. The by-pass filter element was changed at 12,500 mile intervals for the duration of the test.
Following the year-long demonstration, each of the engines was disassembled, both to determine the levels of sludge, varnish, and rust that had accumulated inside the engine, and to carefully measure the amounts of wear experienced on critical engine components. Pictured on the previous page are representative samples of various components of the test engines. In the first example, the pistons and intake valves of the petroleum Control Group (*oil and filter changes every 3,000 miles*), are illustrated. The lower set of photos represent the same engine components from an Amsoil Group 3 vehicle. Note the substantially reduced varnish and sludge deposits on the synthetic-oil lubricated components, and the remarkably good overall condition of the Amsoil Group 3 piston rings and valves.
To summarize the findings and conclusions, the test facility responsible for the demonstration submitted this statement: "The data presented in this report indicates that the Amsoil synthetic SAE 10W-40 passenger-car motor oil formulation...provided protection of the test engines from excessive wear and deposit formation, far beyond the normal 3,000-mile change interval." In fact, the level of protection was such that those engines in which the original synthetic oil was run for the entire duration of the (60,000-mile) test showed less wear than did the Control Group vehicles using premium, 10W-40 petroleum oil and 3,000-mile drain intervals.
Good luck... GUSTO
Last edited by GUSTO14; Jun 7, 2018 at 10:41 AM.
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Instructor
Joined: Nov 2012
Posts: 125
Likes: 18
From: Gonzales CA
Frequency of oil changes
I use Mobil 1 5W-30 and Mobil 1 filters. Generally in all of my cars I change oil and rotate tires at 5,000 miles. In my '03 Z06 I watch the oil monitor and send oil to Blackstone Labs. Last oil change was over 9,000 miles (9% life left) and they said I could go 12,000 miles based upon their findings. I just changed it at 8,000 miles and it was at 16%. Curious as to their findings this time. May go back to 5,000 mile changes in the future. Save the wave
Racer
Joined: Mar 2018
Posts: 454
Likes: 200
From: Chicago
2020 Corvette of the Year Finalist (stock)
C5 of Year Winner (stock) 2019
I had a 2009 Pontiac G8 GT. The 6.0 in that held 9 quarts. That was an expensive oil change if I took it to Jiffy Lube. I started doing it myself and did it once a year with Mobil 1.
Safety Car
Joined: Jun 2017
Posts: 4,786
Likes: 425
From: North Georgia, USA
Just change the filter and top off what was in the filter. The filter traps all the metal shavings. Also get a magnet for the bottom of the filter you will be surprised what that will pull out of the oil. If you see heavy metal particles change all the oil. Use only GM filters they are the best. Shine a led lite into the waste oil and you should see suspended particles the filter trapped.
For your engine, especially for the LS1, GM (AC-Delco) filters are probably the worst possible choice. The PF-46E filter has a flow capacity of 3 GPM. The LS1 oil pump flows between 4 and 7 GPM across most of the RPM range. So that filter is restrictive, and the bypass valve on the oil filter bracket pretty much runs open all the time. That filter almost never gets the full flow of oil from the pump.
The Wix 51042 (also Napa gold or Car Quest blue) is rated at 9 to 11 GPM. Most of the other aftermarket filters for this engine are rated over 7 GPM, so most will filter the full flow of the oil pump.
As to the rest of your post, if you're running oil for an extended time between changes, changing the filter at the factory change interval is usually a good idea, even if you don't change all the oil at that time.
I still recommend annual oil changes as a bare minimum. Condensation collecting in the oil can cause problems, and that happens even when the thing is parked.
Last edited by C6_Racer_X; Jun 12, 2018 at 03:33 PM.
