Why change synthetic oil every 3,000 miles?

[C-ya]

My OLM says i got about 70% left on it. So you guys just go by that, change it when it gets down to like 10%? or if its been 6 months to a year since the last change?

That all depends on if the OLM was reset at the last oil change. I plan to go to about 5-10% before changing mine. If you are getting close to a year, then the consensus of the group is to change it at least once per year. Make sure to reset the OLM when you change oil!

 

[DARKASS04EXT]

Can the OLM actually tell the difference if your running dino or full syn oil?

 

[Matt]

Can the OLM actually tell the difference if your running dino or full syn oil?

No. It's just a "computer program". It can't tell if you've got dino, syn or veggie oil in it, it goes by the way the truck is driven.

I change mine (synthetic) when it gets to 10%, which coincidentally works out to be once a year. This year though, I plan on changing it in May or June because the yearly change is December and I'm getting too old to be crawling around on a freezing garage floor!

 

[Rudeawakening]

That all depends on if the OLM was reset at the last oil change. I plan to go to about 5-10% before changing mine. If you are getting close to a year, then the consensus of the group is to change it at least once per year. Make sure to reset the OLM when you change oil!

Yeah, its reset after every oil change.

 

[seanpooh]

I don't care how good anybody's oil is, I'm not leaving it in there for 20K+ miles!

I think I'll leave my oil in for 20K miles.. Of course I will post up the analysis I'm only at 6K miles/3 months on this change now. 7 more months...

 

[Bartonmd]

The life of oil is based on alot of things-heat/ cold, dust, humidity, short/long trips, speed, idle times, how many times you floored it etc. The OLM is based on complex set of algorithyms in the memory of the ECM. So you know GM would not allow it to be stretched to the very end of the oil's usefulness-its a conservative measurement to be sure. 3K is passe!!

It's not that complex, from what I can find out. I gather that it's just a cycle counter that weights cycles based on load and temperature. This is the way we were told it was when I was doing my automotive controls specialization in college, in 2003. I don't know if they've changed it since then, but I haven't seen anything different in print, so that's what I'm going with for now. This is, however, remarkably accurate, but doesn't take into account things like dust, premature wear of something out-of-spec, coolant getting in the oil, fuel getting into the oil from a bad O2 sensor making it run really rich, etc.. So, if you run a K&N air filter (that lets in 100x more dirt than stock), and/or drive a lot in the desert/dust/offroad, I wouldn't go by the OLM. Also, if you're going through coolant, or are getting really bad mileage, I wouldn't go by the OLM. Also, if you're really modified, there are things that can throw it off (load that the computer thinks it sees vs. actual load vs. fuel vs. how rich you are on WOT compared to stock, etc.) For most normal situations, though, it's really pretty accurate on oil additive useage, despite how simple it is.

Mike

 

[Rudeawakening]

A friend of mine brought this up. I told him that im going to switch to synthetic oil. He said it might be a bad idea if engines whole life has been conventional becuase the engine has been broken in with convential oil and not snythetic. The only thing I can think of that would be a problem is viscosity, but thats why you buy the certain grades (10w-30, 5w-20, ect.) What do you guys think? Does it matter what the engines oil past was when you want to run synthetic or viceversa?

 

[Bartonmd]

It doesn't matter at all. The only problems that some people had, when dino oils weren't NEARLY as good as synthetics, was that you'd get wax buildup from regular oils, that would plug leaks that were there anyway, and the extra additives in synthetics would break up those deposits, and would cause a leak that was there in the first place to finally show up. Because of this, there got to be a myth about synthetics making your engine leak, but that's not really the case, especially with the better designed engines we have now, and the better dino oils that we're running anyway.

Mike

 

[Rudeawakening]

Im probably gonna go with mobil one synthetic oil, but still undecided of what filter. I want a filter to last as long as the oil. I have heard AC delco, but iv seen the study on it and it said it was a poor filter. I googled high mileage oil filter and all that came up was fram,no way im using fram. 90% of my driving is highway, im looking to change the oil and filter 6k-7.5k all at once. Pureolater seems to be the one many people like that also seem to have good reviews so im leaning towards that one. What do you guys think?

 

[CaptainXL]

Im probably gonna go with mobil one synthetic oil, but still undecided of what filter. I want a filter to last as long as the oil. I have heard AC delco, but iv seen the study on it and it said it was a poor filter. I googled high mileage oil filter and all that came up was fram,no way im using fram. 90% of my driving is highway, im looking to change the oil and filter 6k-7.5k all at once. Pureolater seems to be the one many people like that also seem to have good reviews so im leaning towards that one. What do you guys think?

AcDelco filters are more than likely the safe bet. Good filters are using the e-core design such as the ACDelco PF-61e. As far as oil goes I would go with the Walmart Supertech fully synthetic produced produced by Warren. It's a great oil and you save a ton of money to boot. I have been using the Supertech with regular 6K oil changes and flushes. It might take a year or two to rid your engine of evil deposits. I used to have a ton of lifter noise and now none. So do what you want as far as brand but I think my synthetic strategy is pretty sound.

 

[Rudeawakening]

After doing alot of research, iv decided to go with mobile synthetic with a napa gold filter. I think 7500 miles on it is a safe bet. When I was in pepboys, I came across mobile extended performance. When used with the mobil oil filter (which seems to have one of the best revies, even better than napa/wix) you can safely get 15000 miles on it or 1 year. It only cost about $1.50 per more per quart. Im really considering doing that. Have any of you guys have any experience on it?

 

[DFWWIZ]

After doing alot of research, iv decided to go with mobile synthetic with a napa gold filter. I think 7500 miles on it is a safe bet. When I was in pepboys, I came across mobile extended performance. When used with the mobil oil filter (which seems to have one of the best revies, even better than napa/wix) you can safely get 15000 miles on it or 1 year. It only cost about $1.50 per more per quart. Im really considering doing that. Have any of you guys have any experience on it?

You're safe doing that. I've been using Mobil 1 since 1980 in all of my vehicles. My 79 Monte Carlo retired with 240K miles, my 86 Monte Carlo SS had 172K mileson it before we refreshened it. My 93 Jimmy went 141K miles before I sold it to a friend, my 07 MCSS currently has 84K miles on it and my 07 TBSS has 77K miles presently. On the 2 older Montes I used to change the filter and add a qt every 5K miles and then a complete oil change once every 25K miles or once per year. The 2 07's I currently change it when the OLM tells me to.

 

[MDBT]

Take pity on the OLM worshipers for the wear they will suffer. At least if you change too often all you destroy money in small, easy to swallow increments. While not optimal it's still better in the long run than destroying metal.

That said if you are a chronic oil changer at least Valvoline will extend you a warranty for your tom foolery.

Owners of 5.3L DOD V8's rejoice. You have a built in oil change system that automatically drains 1 quart every 1k miles so your oil is always fresh.

This topic is a flame waiting to spread and it seems to get ignited on a regular basis. There's such a wide range of opinions and anecdotal evidence combined with endless variables that I'm sure it'll continue to be a hot topic.

 

[CaptainXL]

For the most part people should follow the advice in their owners manual rather than the oil change business.

In our case this would mean following the OLM which usually lights up around 8-12K depending on engine load and revs. If it doesn't ever light up the owners manual states to change the oil once every year. And isn't that what we have heard mechanics say all along? Make sure to change it at least once a year. Heck I would have to guess that 75% of cars out on the road maybe get the oil changed once every 1.5 - 2 years. So I don't see what the big deal is with following the OLM or GM's recommendation.

 

[Sparky]

Following the OLM with synthetic and at 171k miles and counting <shrug>

 

[DFWWIZ]

Following the OLM with synthetic and at 171k miles and counting <shrug>

There ya go-REAL WORLD experience!! Thanks Sparky, this says alot about the "preachers" preaching doom if you follow the OLM.

 

[DFWWIZ]

Take pity on the OLM worshipers for the wear they will suffer. At least if you change too often all you destroy money in small, easy to swallow increments. While not optimal it's still better in the long run than destroying metal.

That said if you are a chronic oil changer at least Valvoline will extend you a warranty for your tom foolery.

Owners of 5.3L DOD V8's rejoice. You have a built in oil change system that automatically drains 1 quart every 1k miles so your oil is always fresh.

This topic is a flame waiting to spread and it seems to get ignited on a regular basis. There's such a wide range of opinions and anecdotal evidence combined with endless variables that I'm sure it'll continue to be a hot topic.

Sparky just torched your flame. Your opinion is just that and you are entitled to it. Believe what you want. But what Sparky, CaptainXL and I have presented is REAL WORLD FACTUAL evidence, that you do not have to change every 3K miles. As long as the dip stick reads full and you use a GOOD oil-synthetic/blend/whatever, you will not "blow up" your engine. With tolerances that have gotten much tighter, newer technologies, less contamination of the oil and ECM/sensors to warn you, the 3000 mile oil change is a thing of the past - only a scare tactic to put money in the pockets of the people who rely on it for their business. Unless you are on the strip, racing or a hammer-down-all-the-time type driver all you are doing is wasting $ that you don't need to be doing (with this liberal economy taking more and more) as well as a waste of resources. People who fight everyday to keep in line with a budget with what little money they make don't need to be scared into unnecessary spending by doomsday sayers.
And where do you come up with the 5.3 DOD BS???? My wife has it in her 07 MCSS and it is still like new with 84K miles on it, gets 20.3 MPG in the city, and may use 1 qt in 6-7K miles!!!

 

[Sparky]

I don't think MBDT is suggesting the 3K changes. Note his second line about being a chronic oil changer (lol that's a good way to put it). I suspect he's recommending something more in the middle like 6k or something perhaps.

 

[Bartonmd]

Take pity on the OLM worshipers for the wear they will suffer. At least if you change too often all you destroy money in small, easy to swallow increments. While not optimal it's still better in the long run than destroying metal.

That said if you are a chronic oil changer at least Valvoline will extend you a warranty for your tom foolery.

Owners of 5.3L DOD V8's rejoice. You have a built in oil change system that automatically drains 1 quart every 1k miles so your oil is always fresh.

This topic is a flame waiting to spread and it seems to get ignited on a regular basis. There's such a wide range of opinions and anecdotal evidence combined with endless variables that I'm sure it'll continue to be a hot topic.

Actually, per an SAE peer-reviewed research study of used oil analysis on newer oils, it would seem that the newer oils (keep in mind, this is as of 5-6 years ago, so it has been the case for awhile) have to somewhat "break in" via heat and pressure, before they really start protecting like they are capable of doing, being that the additives aren't "active" in the bottle, so to speak, any more. Turns out that 90% of the wear in an engine occurs in the first 1000 miles after an oil change, and wear doesn't start going up until after the additive package (TBN) is used up. So, if somebody changes their oil every 3000 miles, instead of every 9000 miles (if that's where the OLM tells them to change), they're putting around 3x the wear on their engine, compared to the guy that changes his oil every 9000 miles. Turns out that dispersants require time to bond to the wear metals and byproducts in your engine oil, so before they become active, these things can clump together, to the point that they get big enough that they cause wear in your engine.

The paper is called: Title: Extended Oil Drain Intervals - Conservation of Resources Or Reduction of Engine Life (Part II)"

FWIW, I have an '07 TB that burns 1/2 quart in 10,000 miles, from 20k until the 100k that it has right now. There is a TSB for these things burning a lot of oil, too. It's apparently the AFM valve in the crankcase that can spray a lot of oil out, which ends up getting on the cylinder walls and making deposits, which cause it to burn oil. The TSB is for a new pan gasket with what's basically like a windage tray attached to it, and clean the cylinder walls by pulling the plugs and spraying in the top end cleaner, and letting it sit for a couple hours. The supposed "not-stock" fix is to turn off the DOD with a tune.

Mike

 

[MDBT]

I don't think MBDT is suggesting the 3K changes. Note his second line about being a chronic oil changer (lol that's a good way to put it). I suspect he's recommending something more in the middle like 6k or something perhaps.

Correct, I believe that the OLM and the 3k rule are two extremes of the situation and now that my GMT has stopped using the oil I intend on finding a happy medium mileage range to use as a guideline.

Sparky just torched your flame.

My post was a good-natured ribbing of the opposite ends of the spectrum. I didn't "flame" anyone or even directly respond to or quote an individual post.

My REAL WORLD EVIDENCE (not a fan of caps but "when in rome") comes from my company's small fleet of 5-8 vehicles purchased new every two to four years usually ranging between 20 and 40k miles on each per year. We used to change fairly frequently at 4-5k. Believing this was a waste of money and jumping on the "GM knows best" philosophy also popular here the company policy changed to following OLMs. We later put a maximum mileage cap as quiet, low mileage engines demonstrated dramatic valve train noise after waiting for the OLM to drop below 5%. Oil levels were checked regularly usually dropping into a service center for a fluid top up. When you hear one of the 2.4L 4cyl cars that has been stretched too long it sounds like it might have a TDI badge on the back. This issue was seen with I4 car engines as well as V6 and V8 truck engines all from GM.

I don't want to get into a pissing match over who has more "REAL WORLD FACTUAL EVIDENCE" because neither of us has even the beginnings of a truly scientific study. Your hand picked group of 3 people is no more statistically significant than my experiences when compared to the total number of OLM equipped GM vehicles. I respect Sparky (I haven't been around long but I can see he knows his stuff) and I feel as though he's a big enough boy to make his own decisions. Most of the opinions posted here are the result of personal experience and few posters who have a strong opinion are likely to change it because 3 people had a different one. Experiences differ so opinions do as well and that's ok.

As for the DOD/AFM oil use, you're out of your element. Any time GM has to issue multiple TSBs spanning multiple years and versions of engines you don't get to declare the problem "BS". I was speaking of my Saab and the LH6 has a storied history with oil use. Don't believe me? Feel free to check this forum and the OS. GM even made a replacement part for my problem, I installed it and thank goodness it actually worked. As for your wife's LS4 it is great that you lucked out but it's not immune to the problem either: LS4 that burn oil step in here. - LS1TECH (link contains LS4 TSB)

 

[MDBT]

The paper is called: Title: Extended Oil Drain Intervals - Conservation of Resources Or Reduction of Engine Life (Part II)"

FWIW, I have an '07 TB that burns 1/2 quart in 10,000 miles, from 20k until the 100k that it has right now. There is a TSB for these things burning a lot of oil, too. It's apparently the AFM valve in the crankcase that can spray a lot of oil out, which ends up getting on the cylinder walls and making deposits, which cause it to burn oil. The TSB is for a new pan gasket with what's basically like a windage tray attached to it, and clean the cylinder walls by pulling the plugs and spraying in the top end cleaner, and letting it sit for a couple hours. The supposed "not-stock" fix is to turn off the DOD with a tune.

Mike

Interesting study, would seem to indicate that the time between changes isn't as vital as we're making it out to be.

The most current TSB for 06/07 models (many of the initial TSBs have been superseded) specifies fitment of a new valve cover with a redesigned/relocated baffle. I put one on and went from 1 qt per 800 miles and constant frustration to one drip per 1k miles. This has also made the truck's other little foibles much easier to deal with. Highly recommended for those suffering from this ailment with 06-07 models.

 

[Bartonmd]

Interesting study, would seem to indicate that the time between changes isn't as vital as we're making it out to be.

The most current TSB for 06/07 models (many of the initial TSBs have been superseded) specifies fitment of a new valve cover with a redesigned/relocated baffle. I put one on and went from 1 qt per 800 miles and constant frustration to one drip per 1k miles. This has also made the truck's other little foibles much easier to deal with. Highly recommended for those suffering from this ailment with 06-07 models.

Correct.

I had seen the new valve cover as part of the series of things in the TSB to cure the oil burning; but on other similar DOD 5.3L engines, it seemed like people had tried the valve cover, and it didn't work, but they did cure it by the windage tray / oil pan gasket and cleaning the bores, and sometimes replacing the rings. Still, other people have done just the valve cover, and that fixed it. Seemed like the deal on some was that the PCV that's built into the valve cover had become stuck open, and the new one fixed it. People had gone from not burning any oil, to all of a sudden burning a quart in 1k miles, which would make sense for the PCV sticking. To be honest, though, I haven't spent a whole lot of time looking into it, because mine has been fine.

Mike

 

[MDBT]

Gotcha. I had seen a gasket TSB for the 08+ LH6 on a GM pickup forum where it seemed to supersede or append to the valve cover TSB but I missed that the procedure you mentioned applied to other models and years as well. Honestly once I found the valve cover TSB and verified the part number I assumed it was my best hope short of a top end rebuild.

Now that I get to do oil changes instead of just refills I'm not sure how often I'll need them. I drive around 8-9k per year but most of that is in lumps of 600 miles or more at a time with a lot of sitting stationary in between trips. Probably once in the beginning of spring before my travels and again before the holidays.

 

[Bartonmd]

Gotcha. I had seen a gasket TSB for the 08+ LH6 on a GM pickup forum where it seemed to supersede or append to the valve cover TSB but I missed that the procedure you mentioned applied to other models and years as well. Honestly once I found the valve cover TSB and verified the part number I assumed it was my best hope short of a top end rebuild.

Hey, if it worked, it worked!

Mike

 

[Sparky]

My valve train sounds the same at the time the OLM light kicks on as when I first put the oil in nice and fresh. Trust me, if the engine changed sound any I'd be changing far sooner!