Synthetic oil question and oil change intervals?

[C-ya]

mine started going off for the first time like 1000 miles after my last oil change... WTF is that all about? oh well everything looks, smells and acts fine lol. I will just keep up at around 8000 miles for changes

You have to reset the OLM. There should be a procedure in your owner's manual. The OLM isn't reset automatically when you change the oil.

 

[Sparky]

I had it done twice in fact. Maybe that was what did it, but I do not know why they would even bother touching that aspect.

I believe PCM4L uses the most recent base GM tune for what they work with, so that would reenable the light. Makes sense.

 

[djthumper]

I believe PCM4L uses the most recent base GM tune for what they work with, so that would reenable the light. Makes sense.

Hmmm now that would be interesting if that was to be true.

 

[jfkmk]

I would never go 25,000 miles. Even if the oil might be good that long (doubt it!) the filter should still be changed before then more than likely.



I would also suggest against using 10W-30 over 5W-30. There is NO point to doing that. At operating temperature they are both the same, but at cold temps the 10W is thicker than the 5W, so it won't flow as quickly. These engines were designed with 5W in mind at cold temps, not 10W. If you have to use 10W-30 to keep it from leaking or smoking, well, your engine is about worn out. Using thicker oil is just a mask.

Thanks for bringing that up, Sparky, I was going to make the same point. To go to a 10w over a 5w is very foolish. I'm from the same state as the original poster, and it can get pretty cold here. To go to a higher "winter weight" is asking for trouble.

As far as these extended oil changes, I would never go beyond a year no matter what kind of mileage I've had since the last oil change.

 

[Frankd1]

I have been using Castrol GTX synthetic, 5w30 and Purolator Pureone filters. So far so good, I may switch over to Mobil 1 syn just to try something new. I have been happy with the Pureone filters so no need to change those I guess!

 

[TB2004]

I use Amsoil 5w 30 with the ea oil filter and change it at 25,000 miles or 1 yr which ever comes first. Used to drive 80,000 miles plus a year and this oil is great. If I have it I add prolong too, it really eliminates the friction and heat. Would go 250,000 to 300,000 before getting new vehicle. Repairs and problems were far and few between.

 

[smt 59]

Not to sound old but I have been using Amsoil since 1978 as my dad was one of the first dealers in Canada. I have used it in everything from my hot rods to my toys,boats etc., you need to get on the Am soil website and read up on it. It is just not about cost and change intervals, it is quality and what it does in regards to performance and not breaking down, reduced friction etc.
look at your driving environment as well,stop n go, highway,dust, dirt etc. It's like fram filters used to say. 'Pay me now or pay me later.

 

[strat81]

I have been using Castrol GTX synthetic, 5w30 and Purolator Pureone filters. So far so good, I may switch over to Mobil 1 syn just to try something new. I have been happy with the Pureone filters so no need to change those I guess!

Castrol GTX is not synthetic. The white bottle GTX is dino sauce, the green bottle GTX is high mileage, and the silver bottle GTX is a synthetic/dino blend. Good oil, a friend's father took a Ford 5.0L over 300k miles with GTX with no lubrication issues. He used it as a cab and would change the oil weekly. He had cases of it stacked in the garage.

(ETA - Admittedly, the GTX of today is quite different than the GTX of 20 years ago.)

 

[davenay67]

I have a friend over on another forum, who has only used Castrol GTX in his motorcycle. The bike is well over 275,000 miles and running strong.

Larger normally aspirated engines like the I6 seem just fine on dino and blends, but the move the new movement towards Eco Boost engines (nice sales job by Ford to simply do what the Euros have been doing for decades by adding a turbo to a smaller displacement engine) is requiring synthetic for the higher stresses and heat generated by these turbos.

 

[strat81]

I have a friend over on another forum, who has only used Castrol GTX in his motorcycle. The bike is well over 275,000 miles and running strong.

Larger normally aspirated engines like the I6 seem just fine on dino and blends, but the move the new movement towards Eco Boost engines (nice sales job by Ford to simply do what the Euros have been doing for decades by adding a turbo to a smaller displacement engine) is requiring synthetic for the higher stresses and heat generated by these turbos.

Agreed.

Also, with the increase in use of variable valve timing systems, cleanliness is even more important as sludged components can cause problems. Since synthetics are often more resistant to heat degradation which can cause sludge, they are becoming more common, as are synthetic blends (Dexos1 anyone?) which can share some of those properties. Cold flow and shear resistance can be better with synthetics too.

That said, dino sauce is getting much better these days, and not all users need the benefits offered by synthetic oils.

Keep your eye on rebates and sales, and you can sometimes pay dino prices for synthetic oils.

 

[IllogicTC]

Agreed.

Also, with the increase in use of variable valve timing systems, cleanliness is even more important as sludged components can cause problems. Since synthetics are often more resistant to heat degradation which can cause sludge, they are becoming more common, as are synthetic blends (Dexos1 anyone?) which can share some of those properties. Cold flow and shear resistance can be better with synthetics too.

That said, dino sauce is getting much better these days, and not all users need the benefits offered by synthetic oils.

Keep your eye on rebates and sales, and you can sometimes pay dino prices for synthetic oils.

It's funny when some synthetics are literally just dino that's been processed further they just pick out the parts of the dino they want!

A lot of this stuff is coming from forced advancement by the government to meet higher and higher emissions and fuel mileage standards. Eventually it won't be asking to see ASE certification when looking into a new shop, it'll be asking to see their doctorate degree in engine mechanics

 

[strat81]

It's funny when some synthetics are literally just dino that's been processed further they just pick out the parts of the dino they want!

If it performs as intended, I don't care what it's made of.

Manufacturer's ratings such as BMW LL-01, Honda HTO-06, Porsche A40 are very difficult to meet. Even a 0W-xx viscosity is (relatively) hard to meet.

And then there's stuff like this that make 5W-30 cultists apoplectic:
http://www.mobil1.lt/galery/_mobil1/autosportas/corvette_mobil1.pdf

 

[glfredrick]

I use the XL which is right around 5-6 dollars a quart (full synthetic) I keep it in around 8-10k depending on how hard I drive it. The OE is even less then that around 4-5 a quart. More than what you pay for the dino oil but I'm getting synthetic and its goooooooooooooood.

Unless your looking at the Amsoil racing oil you shouldn't be paying 10 a quart.

I have been using Amsoil on "extended drain" intervals since the late 1970s when the product began to be introduced publicly.

But know that there is a difference between the formulation of their XL brand and their "signature" brand. The XL is not actually rated for extended intervals, even though the name suggests that it is. It is a Group III synthetic (made from dino oil base stock, re-cracked, i.e., further refined) instead of the better all around Group IV base stock (PAO -- pure and true synthetic) of their signature line. It is worth the difference in money to go with their signature oil instead of the XL, which is basically the same as Valvoline, Castrol, Mobil 1 (non extended, their extended is PAO Group IV), etc.

It is this nomenclature that gets people confused as to what is REALLY synthetic oil and what is not really synthetic oil, though all the labels say the same.

Understanding the Differences in Base Oil Groups

The technology of synthetic oil. How is synthetic oil made?

Is Your Engine Oil Really Synthetic? | Lubrication Engineers of Canada

 

[HARDTRAILZ]

GLF...isn't your truck being "prayed" for due to issues and your worry of it not lasting? Not a good indicator of synthetics effectiveness.

 

[strat81]

But know that there is a difference between the formulation of their XL brand and their "signature" brand. The XL is not actually rated for extended intervals, even though the name suggests that it is. It is a Group III synthetic (made from dino oil base stock, re-cracked, i.e., further refined) instead of the better all around Group IV base stock (PAO -- pure and true synthetic) of their signature line. It is worth the difference in money to go with their signature oil instead of the XL, which is basically the same as Valvoline, Castrol, Mobil 1 (non extended, their extended is PAO Group IV), etc.

What is your source for the base oil group types of the various manufacturers? To my knowledge, none of the major oil companies disclose what group types are found in their oils, and/or in what ratios (i.e., Brand XYZ oil may use 55% group IV, 40% Group III, and 5% Group V but they won't tell you that).

Complicating the matter further is GTL (Gas-To-Liquid) base stocks which are classified as group III but are not made from crude oil (they're made from natural gas).

 

[triz]

If it performs as intended, I don't care what it's made of.

Manufacturer's ratings such as BMW LL-01, Honda HTO-06, Porsche A40 are very difficult to meet. Even a 0W-xx viscosity is (relatively) hard to meet.

And then there's stuff like this that make 5W-30 cultists apoplectic:
http://www.mobil1.lt/galery/_mobil1/autosportas/corvette_mobil1.pdf

Ironic that in the 70's, GM really did not even remotely look to embrace any type of synthetic oil at all. I uploaded a article from a 1976 Popular Mechanics magazine in our boxing thread if you care to read it. Pretty cool read I think personally.

 

[Mmmm bacon!]

Somehow I just stumbled on it and read through. I understand that 99% of people are steadfastly in one camp or the other, with zero chance of anyone changing their attitudes about the dino/synth question. Just the same, I'd like to give my .02 ...

Until retiring three years ago I was an Abrams Tank mechanic in the Army. I maintained a wide variety of vehicles, though. Anything assigned, whether tracked or wheeled. During my 20 years (active, not a weekender), the rules on oil service varied about zero. Oil life was measured only by an oil analysis, and was changed only when:
1) a sudden change in wear metals or contaminants was detected, or
2) a certain threshold of concentration of contaminants/wear metals was reached, or
3) the oil had to be drained to perform other repairs.

Sometimes, we'd get a notice to change only the filter and re-sample immediately or after some predetermined period of operation.
Sometimes we'd get a notice to cut the next sampling period in half. Analysis results were generally only reported back to us if they were bad, but we could obtain a roll-up report for all our assigned vehicles.

For a little while when I was but a young Soldier, it was my job to also drive our motor sergeant's HMMWV. It being my baby, I really wanted to look after it, so one time I serviced it out of schedule and filled with Mobil 1 I had at home. The lab flagged the next sample because of the change and I had to fess up to what I'd done. My shop foreman had a good relationship with the folks over at the lab so we didn't change it back to the approved oil. He kept tabs on the analysis results on my truck, and a couple years later we still hadn't changed the oil in it. Meanwhile, the remainder of our wheels all had to have oil changes. That was enough evidence for me to know that a synthetic was better.

I'm sure most guys have peered into the area under their oil cap. On most vehicles I've looked into it's never been anywhere near clean. I recall one friend who was a lifetime penzoil fan because his daddy told him so. His camaro got so full of crud that he wound up with a really bad oil leak from the valve cover on one bank. He changed the valve cover gasket a couple of times before he decided to ask around. We determined he had clogged drain passages, causing oil to fill the area around his valve train. Once sufficiently full it would push out the gasket. We pulled him into the bay and pulled the valve cover, and used a power drill and heavy wire to "drill out" the crusty garbage. He switched to synthetic and after a few oil changes pulled the valve covers because he got some shiny new chromed covers that were good for at least as much HP as the stickers on his windows. I didn't see with my own eyes, but he reported that the built-up deposits he'd grew up thinking were normal just weren't there anymore. I think he was a lifetime convert after that.

For a few years I enjoyed chasing (and killing) cones on the weekend. Like most autocrossers I ran what I had, which for me was a 96 Monte Carlo Z34. It was a heavy, underpowered, ill-performing beast of a FWD car. I bought it with about 36KMi on the clock, but fed it only synth the whole while I had it. One time I took my neighbor's son with me to an event about 150 miles away. I discovered I had a blown head gasket after my first angry lap that day, and didn't bat an eye. He co-drove with me and we put 16 or so good runs on it before packing up at the end of the day and heading home. We got within 40 miles of home and had to stop because there was litterally no coolant left. We pulled into a Hooters, ordered beers and food, and called a tow. It was so hot when we stopped that the cooling fans ran the battery completely down. Keyless entry, courtesy lights, nothing. It was still pretty frickin' hot when the tow showed up. He hauled it home for me, and I did the repairs in my garage at home. By then it had about 100K miles on it. The heads were still planar, and I only replaced gaskets. I continued racing the car after that, even winning a touring series championship with it in a class that was dominated by the Subaru WRX. After the championship win I moved to a more proper sports car (an S2000) and sold it to another friend's son within spitting distance of 200K miles. Two years later it developed an oil leak due to a bad o-ring on the pil pump drive (imagine just the bottom half of a distributor). That repair required pulling the front cyl head to be able to remove the drive. My friend (the buyer's dad), has been a mechanic longer than I've been alive (I'm now 40), and could not believe I didn't rebuild the engine before I sold it. The cylinder walls were pristine, still bearing honing marks. The cam carriers, valvetrain, cyl heads, etc were clean as a whistle. He wondered how the engine was so clean, and so apparently fresh looking, with so many miles. I told him I'd fed it only synthetics since I bought it. He is a lifetime convert now, as well.

I admit that is a little more than $.02 worth of post, but I have had nothing but excellent experience with synthetic lubricants. Before I was a synthetic user I'd had rod bearings spin due to oil starvation. I'd had a small engine seize when overheated and barely low on oil. On synthetics I've seen a double-gasketed oil filter spill all the oil out and the engine run on zero oil pressure a mile to a gas station, but suffer no consequences.

The way I see it you can surely get by using conventional motor oils if you're careful to change them with some form of regularity and you don't really abuse the engine. When you do require repairs it may cost you a little more, but you'll have saved a little money buying cheap oil so you might not mind. If you are prone to abusing an engine, or are not so careful to mind some sort of service schedule, then synthetics are definitely for you. Also, if you've already spent the 10% money to get 90% of the available power improvements, and the 90% money to get that last %10 in improvements, then you might as well not throw it all away on even a momentary oiling problem.

I change engine oil annually because I'm too forgetful or lazy to mess with oil analysis. I rarely go over 15K miles in a year. Wally-world sells 5qt jugs of M1 5W-30 for less than $30 all the time, and a couple decent filters a year (one mid-year, one at oil change) puts you in for what, $60/year? That's damn cheap insurance to me, and I KNOW my oil is good, whether I just poured it in or it's been in there six months.

I'll admit I'm a bit of a cheap bastard, but feeding your engine anything less than a high-quality synthetic is just foolish.

</rant>

 

[glfredrick]

GLF...isn't your truck being "prayed" for due to issues and your worry of it not lasting? Not a good indicator of synthetics effectiveness.

I'm at over 150K miles and it is still running, albeit making a noise from the front of the engine.

I've run Amsoil XL oil in the beasty instead of their signature oil. Just learned the difference myself... Shame on me. "Thought" it was the good stuff. That being said, I've still only changed oil once per year on this vehicle since I've owned it.

But in any case, I'm still not using or burning any oil, and the vehicle runs well for 150K of hard driving, often towing 8000 lbs across country.

Mostly the normal Trailblazer nickle and dime stuff that gets really agravating after a while because it goes out like clockwork and I'm on my second go-round for many of the common failure items.

What is your source for the base oil group types of the various manufacturers? To my knowledge, none of the major oil companies disclose what group types are found in their oils, and/or in what ratios (i.e., Brand XYZ oil may use 55% group IV, 40% Group III, and 5% Group V but they won't tell you that).

Complicating the matter further is GTL (Gas-To-Liquid) base stocks which are classified as group III but are not made from crude oil (they're made from natural gas).

If one digs a bit that information can be found. For instance, Chevron, who only uses Group II base stock:

Frequently Asked Questions

Group I oils contain high levels of sulfur and aromatics, which are compounds that can diminish performance. Group II & III oils have almost none of these impurities, which result in enhanced oxidation performance for fully-formulated lubricants. Thanks to Chevron's proprietary ISODEWAXING technology, Chevron's Group II and II+ base oils also have very low wax content, which delivers better low-temperature performance compared to many other base oils. Due to their high level of purity, Chevron Group II & II+ base oils provide additional benefits in crankcase applications. For example, in heavy-duty engines, motor oils made with Chevron base oils have demonstrated a soot dispersancy markedly higher than those made with Group I base oils.

Here is a more detailed look at the various base stocks, their performance designators, and recommendations from major truck engine manufacturers (highly technical):

http://www.api.org/certification-pr...sel/publications/appendix-e-rev-09-01-11.ashx

Amsoil tells the world that its XL product is Group III and that its Signature line is Group IV. Same with Mobil 1 (historically -- they have since declined to say). Other oils simply do not have access to Group IV so they MUST be using Group III at best.

Bob is the Oil Guy also has rather lengthy discussions of all of the above. For instance:

how to tell engine oil in which base stock group? | Passenger Car Motor Oil (PCMO) - Gasoline Cars/Pickups/Vans/SUVs | Bob Is The Oil Guy

 

[HARDTRAILZ]

I'm at over 150K miles and it is still running, albeit making a noise from the front of the engine.

I've run Amsoil XL oil in the beasty instead of their signature oil. Just learned the difference myself... Shame on me. "Thought" it was the good stuff. That being said, I've still only changed oil once per year on this vehicle since I've owned it.

But in any case, I'm still not using or burning any oil, and the vehicle runs well for 150K of hard driving, often towing 8000 lbs across country.

I am over 165K and it is running fantastic. Still impressing me and others with power and smoothness. I change about 5-10K whenever I feel like it or when the light comes on about 10K. Since it is under $20 per change it is a non-issue. Not burning or using oil. Truck is used hard, but no worse for it. Quick starts in the cold, great oil pressure, smooth idle, great running, no smoke, no noises.

I guess the dino/syn blend stuff is as good or better overall. Glad I did not waste any money on some name brand full synthetic.

 

[davenay67]

I was always told by my folks not to discuss religion and politics if I wanted to ensure friendly conversations. Good advice, unbless you like to argue and debate for fun. I think we will be telling our kids not to discuss religion, politics and motor oil.

Oil has come a long way int he last few decades, and engine manufacture is unbelievably accurate these days. I think as long as the car has oil at all it will have a long and happy life. Most of the horror stories about engines failures you will read on the internet are most likely related to oil starvation or a bad component/engine build from the factory.

Now, sludge is anbother matter. I don't think the TB engines are prone to sludge, so some of the benefits of synthetic are a moot point on these engines. My '97 Wrangler (beater car and off-road toy)doesn't care what oil it gets. 190,00 miles strong and it doesn't use even a single drop of oil between changes. I abuse this poor vehicle and it's a superstar. My other car is a '04 VW Passat 1.8T (daily driver) and is notriously prone to sludge. I run Rotella T6 in this car. I know, it's not full synthetic and it's not an apporved oil by VW, but it does the job all the same. I'm at 140,000 miles in this car with great engine performance. It does use oil though. Not burning oil, but losing it though 2 other sources; a leak at the back of the head that I need to address this summer (CCT tensioner gasket), plus some blow-by though the turbo...they all do this, some more than others.

To keep things in perspective for the TB (this is a TB site after all), we should be much more concerned about our tranny's. Tranny problems are much higher on this platform than engine problems. I don't worry much about the life of the engine in the TB, but I sure do have little panic attacks every time I read a thread about tranny problems.

FWIW....the TB is my wifes daily driver. Approaching 149,000 miles. Starts quickly, runs strong and idles so smoothly that I sometimes have to check the tach to make sure it's still even running. I'm sure it had regular dino for the first 100,000 miles. I started maintaining it at the 100,000 mile mark, at which point it has lived on a diet on synthetic blend.

 

[Chris JW]

I am kind of surprised at this thread

I always have changed my oil at 3000 and used valvoline and a fram filter-I didn’t even know there was an oil change light.
my tb is at 130 w/ no engine problems and i have a Buick w/ about 320,00 on it.buick did start losing oil last change though(dont know if its a leak or its burning it)

 

[IllogicTC]

I am kind of surprised at this thread

I always have changed my oil at 3000 and used valvoline and a fram filter-I didn’t even know there was an oil change light.
my tb is at 130 w/ no engine problems and i have a Buick w/ about 320,00 on it.buick did start losing oil last change though(dont know if its a leak or its burning it)

Some amount of burn is expected. Whether it's quantifiable without getting extremely specific with graduated cylinders and whatnot is where the line is drawn. The cylinder will have some amount of oil along the walls where the piston rings travel at all time, and the combustion stroke forces the piston down of course. This in turn exposes the oil that was previously hidden by the rings while at TDC to be exposed to the combustion process.

I've made the change to synthetic but I am not expecting to try going to some outlandish number just because it's feasible. In fact, my last dino change lasted 8k miles and with 4% left on the OLM, but I believe this time I will change after 5k flat, no matter the percentage.

 

[Texan]

My theory is, if it burns one quart in 2,000 miles, it means that the cylinders are getting lubricated.
My 2003 TB with 134K has never had a quart added between changes at 5k miles.

 

[glfredrick]

My theory is, if it burns one quart in 2,000 miles, it means that the cylinders are getting lubricated.
My 2003 TB with 134K has never had a quart added between changes at 5k miles.

No, if one is buring oil they are actually forming hard carbon deposits in the ring lands and around the valves that is seriously affecting the ability for oil to actually lubricate the parts.

 

[bspurloc]

I use Full Synthetic in all my cars because it is really cheap at walmart. The Envoy has 188,000 and not leaking it. It does burn 1-2 quarts between changes which get done with the Oil Life is under 10%. I have never really paid attention to how many miles that is because it is my daughters car. I just started looking since the last oil change and its at 83% life with 4,000 miles travelled. So I would guess it is going at least 10,000 a change.
My Crown Vic with 155k I go 10-15k between changes no leaks and barely burns any oil.