Mobil 1 Users - CEG Archives

most posts I have read about oil change intervals on Mobil 1 that have gotten oil analysis done about 5 to 7 k seems normal

Changing you oil every 3000 miles is overkil for Mobil 1. 5000 miles is ideal.

I change it occasionally. You know just when I feel like it.

5000 miles for me...

Change it pretty quickly for the first few times if your'e switching to synth.

After that 5-7k intervals is good.

I agree with you, Stazi - but since those are 3000 hard miles, and since it only gets about 3000 miles/year (I don't want oil sitting in there that long), that's when I change it.

Yes it depends on driving, but personally don't buy the "sitting" argument for synthetic oil as it's way more stable than regular dyno oil.

It's not so much of a stability question, as it is a question of letting the acid build-up in the oil sit w/o flushing.

I change the oil out every 5000-7000kms. I do my bike about every 2000kms, but it also rev's up to 12K RPMs, heh.

Acid build-up from where????

Acid is only made when the vehicle is running from H2S (hydrogen sulphide) from the exhaust gases, that combines with water to form H2SO4.

When the engine is sitting there how can acid form out of thin air??

It's a myth.

I go 10k and get an analysis each time.

Combustion byproducts - if you would like I can show reams of engine oil data showing the decline in pH over time (as a result of combustion). Granted the data is all heavy duty diesel, though the same lessons apply. Also granted, gasoline on-highway engines are very light duty, so the combustion byproduct creation is siginificantly less (not to mention the differences in fuel, but that's another subject).

I still go every 3000 miles. I'll occassionaly go over to 4000 or so miles, but not that often. I think I put 7000 miles on the car last year, and that's only because I daily drove it while the Sunbird was down for a while. Now that I've got the SHizzO, I hope to only put ~3k miles a year on the Contour.

Mark

I'm not disputng the decreasing pH of an engine that is RUNNING over time. But the pH will not change from when you park the car at the start of winter till the end when you bring it back out.

You are using DESIEL facts in a gasoline engine?!?!? Desiels vehicles don't even use spark plugs for crying out loud. Oil is going to be used diffrently in each type of engine. Why don't I just put 2 cycle oil in my car....you put that into an engine. Just listen to Sazi and Demon in this site...they seem to know what they are talking about.

I change my oil every 4-5 months which is about 4000-4500 miles. That works out to once before winter, once after winter, and once sometime during the summer.

However the best advice has already been given. Get on oil analysis after your second change (NOT the 1st synth fill) at make your own interval. Make sure your first synth fill is a normal interval beacuse it can clean out the build up of conventional oil deposits.

For example the wife's car goes the same 4-5 months but that is 8-10k miles. Both oils analyze close after the same time period but significantly diferent miles and types of driving.

No, you're missing my point entirely. I agree completely with what you are saying. What I am trying to convey is: I run the oil through the course of the year. As time progresses the pH level drops. As you know when the pH drops below 7.0 you are acidic. If I let it sit over the winter before my next oil change, the acidic nature of the oil will start tend to corrode (admittedly not to the point of burning a hole in the block) metals in contact with it. I change it at the end of the year so that clean, new oil is what sits in the engine over the winter. Does that better explain my point?

Yes - that is smart. Change the oil at the end of the season and you're good to go when you roll 'er out in the Spring.

What is stupid is those fools that change their oil at the end of winter, then again when they bring it back out when all it did was sit there. Total waste of money and oil.

Politely I will respond to your reply. The oil in a gas or diesel engine is not used any differently. They both perform the SAME tasks: lubrication, heat rejection, anti-rust, etc. True, the additive packages are different. Heavy duty diesel engine oil is designed for longer intervals between drains, along with some other changes that are not pertinent to this discussion. The fact of the matter is: combustion byproducts (regardless of the fuel) include acids. Let me reiterate, regardless of fuel type combustion byproducts include acids. One of the properties of engine oil is to neutralize acids over time (read up on TBN and TBA). As the service life of the oil increases it loses it's ability to neutralize. Let it go too far and the acids can (and do) damage. No, nothing like burning a hole through your block in a weeks time. It is long term wear items that suffer.
If you want to put 2-cycle oil in your car, go right ahead. I do not put diesel oil in my car. However, the next time you look at a bottle of Mobil 1, look for the latest API deisgnation and notice - right next to the SJ (or whatever the latest designation is) you will also see a C* designation for diesel (compression) engines. Oh, but according to you, that can't be!

Exactly! Sorry to have not explained my position better earlier. No, I don't change it at the end of the year and then 3 months later at the start of next season w/o running the car.

every 4k or so

From my Evo's manual (Evo requires Mobil 1 stock):

3750 under hard use
5000 normal use

Originally posted by Hdbngr8:
Get an oil analysis - that can tell you with better precision how far you can go.

Where do you guys/gals go to get an oil analysis??

Blackstone Lab.

Originally posted by Marky:
Blackstone Lab.

i sent my first mobil one sample in at 140k and i can now go 6k before i need a change.

Originally posted by Hdbngr8:
Politely I will respond to your reply. The oil in a gas or diesel engine is not used any differently. They both perform the SAME tasks: lubrication, heat rejection, anti-rust, etc. True, the additive packages are different. Heavy duty diesel engine oil is designed for longer intervals between drains, along with some other changes that are not pertinent to this discussion. The fact of the matter is: combustion byproducts (regardless of the fuel) include acids. Let me reiterate, regardless of fuel type combustion byproducts include acids. One of the properties of engine oil is to neutralize acids over time (read up on TBN and TBA). As the service life of the oil increases it loses it's ability to neutralize. Let it go too far and the acids can (and do) damage. No, nothing like burning a hole through your block in a weeks time. It is long term wear items that suffer.
If you want to put 2-cycle oil in your car, go right ahead. I do not put diesel oil in my car. However, the next time you look at a bottle of Mobil 1, look for the latest API deisgnation and notice - right next to the SJ (or whatever the latest designation is) you will also see a C* designation for diesel (compression) engines. Oh, but according to you, that can't be!

This is basically correct. Even with little or no sulpher in the fuel (or oil), there is still a lot of acid formed from combustion. This was discovered in the 40's and was the basis for Shell oil company advertising oil with the "X" factor which kept

You missed slightly on the methods of determining the base or acid level in the oil though. TBN is total base number. A high number here shows the base reserve, or is an indication of how much more acid it can handle. The oposite side of this is TAN or total acid number (not TAB).

TBN is generally accepted as the most reliable way to tell if the additives in the oil are depleted. Although rare, it is possible to have a high TBN and still have some of the additives depleted. This is usually only an issue on extremely long oil change intervals.

On the issue of oil quality. The difference in performance between today's conventional oils (dino oil) and synthetic oil is becoming very narrow. The better of today's dino oils are very close in performance to today's synthetic oils. You can easily go 5,000 miles between oil changes on any GF-4 SM rated dino oil except under the most severe usage. And I mean the most severe, not just what most people call "severe duty" that just about defines nearly every driver. It has shifted to the point that unless the car is used in police pursuit or race track use, 5,000 miles can easily be met.

What I'm saying is that today's dino oils are very nearly synthetic oils. The base oil blending stocks are almost equilivent. In fact, some so called synthetics use the same base oil blending stocks as some dino oils (Castrol Syntec and Mobil 5000).

Prior to the latest API certification of SM, I changed the dino oil in my car every 3,000 miles. Before API changed to SM, I changed to synthetic and have been changing it every 5,000 miles. I'm going to switch back to dino oil or possibly move to dino/synthetic blend (Mobil 7500) and stay with the 5,000 mile interval.

Mobil has provided some guidelines. First, they say that if the car is still in warranty, do not exceed the manufactures oil change interval no matter which oil you use. Then they say Mobil 5000 = 5000 miles, Mobil 7500 = 7500 miles, Mobil 1 = 10,000 miles, Mobil 1 EP = 15,000 miles.

An ocassional oil analysis will also help.

If you really want to become more familiar with what is going on in the lubrication industry, hang out for a while at www.bobistheoilguy.com

Originally posted by Big Jim:
You missed slightly on the methods of determining the base or acid level in the oil though. TBN is total base number. A high number here shows the base reserve, or is an indication of how much more acid it can handle. The oposite side of this is TAN or total acid number (not TAB).

Darn it! You caught it before I could correct it

Originally posted by Y2KSVT:

Originally posted by Hdbngr8:
Get an oil analysis - that can tell you with better precision how far you can go.

Excellent advice! I'd personally change it right away on a newly acquired car, just to be on the safe side. Then change it at 3000 miles and send in the oil sample . They'll be able to give you a good idea of how long your motor can go between oil changes.

Mark

where do we send that into?

Like they said.. blacstong labs.

www.blackstone-labs.com.. or.. www.black-stone-labs.com or something like that.. lol

Pay for an analysis (indepth or not..) and they send you a container... use it, mail it in.. and get your results back.

I've been doing my changes every 3-3.5k miles. My driving only slightly spirited and the oil seems to come out too dirty. Mind you the engine has only has 32k on it. I had the change done at a shop last time (its too bloody cold out!!!) and the tech showed me the old oil and again, darker than I would expect. He was telling me to flush the engine, I politely declined.

I seem to have read here that some CSVTs tend to dirty up oil quickly????

Originally posted by SHOgoFast:
I've been doing my changes every 3-3.5k miles. My driving only slightly spirited and the oil seems to come out too dirty. Mind you the engine has only has 32k on it. I had the change done at a shop last time (its too bloody cold out!!!) and the tech showed me the old oil and again, darker than I would expect. He was telling me to flush the engine, I politely declined.

I seem to have read here that some CSVTs tend to dirty up oil quickly????

wont hurt to spend 2 bucks and get some engine oil flush. they have a 5 or 10 min flush. get it at a autozone. you just pour into your oil and run it for 10 mins then drain your oil.

I personally will not change my oil before 5000 miles. Usually once I hit 5000, I wait till I am home to do it. I've run it up to 7500 miles before. On that oil change I took a sample for Blackstone, and I plan on sending it in for an analysis and TBN reading once I have an extra $30 lying around.

I like to keep it clean. I change it every 3000. But if you don't drive it hard you can wait as long as 7000 without doing any harm.

And I imagine that you already know to over-fill the Duratec by .5 to 1.0qt because of starvation on right hand turns.

For clarification:

overfilling by 1 quart would be 6.8 quarts, and would be starting to push what I would do.
Remember: spec is 5.8qts, not the "standard" 5 qts.

6.5 would be the most (safely) that I would recommend) (which I run at each change).

I used to do it at 4,000 but after the last analysis I'm going to start going 7,500. (with mobil 1 and K&N filter)

Jim

Using engine flush once a year is a good thing to do to help prevent varnish ad sludge buildup in the engine and like someone said, it only cost a couple of bucks a can - just make sure you follow the instructions on the can. You're NOT supposed to drive around while the flush is in the motor, only idle the car!

Originally posted by Stazi:
Using engine flush once a year is a good thing to do to help prevent varnish ad sludge buildup in the engine and like someone said, it only cost a couple of bucks a can - just make sure you follow the instructions on the can. You're NOT supposed to drive around while the flush is in the motor, only idle the car!

ya sorry forgot to mention that. if you have it change by a shop or anywhere else maybe you can give the engine flush to them some will some wont depends on where you go. i do my own oil change i cant trust somebody to do mine.

If I were using Mobil 1, I'd be going about 7,500mi between oil changes. Changing at 3,500mi seems like a waste of synth oil to me. I have 9,000mi on the Amsoil I'm running right now.

My car needs a quart about every 1500-2000 sometimes even a little less than 1500...the dealer told me it was considered normal for Fords standards

They also told me the a quart every 1000 miles was still within spec

Running Mobil1 has been very expensive for me but I still run it in all my cars and change the oil about every 3500-4500 miles.

Scott find a new dealer...

Apple Ford in Columbia, MD, This was after they replaced the bottom end (spun bearings) at ~20k miles. At the time it was still under warranty. I have heard this from other Ford long time owners as well...and they like me think it is total BS on Fords part.

My Crossfire has one of those oil monitors and it came on for its first oil change @7000K and it said I could go another 900 miles, so realistically, I could've gone almost 8K

Make sure you use a Mobil 1 or quality oil filter to help things out a bit, its well worth it IMO!