FAQ: Engine Oil - What type and change intervals?

well just changed it with the 5w30 synthetic, seems to run fine

TheNewEra95 wrote:

well just changed it with the 5w30 synthetic, seems to run fine

Owners' manual shows oil weights.

I run 5W-30 in winter, 10W-30 rest of year. Mobil 1 usually, 4 qts of it with 1/2 qt of Shell Synthetic Rotella-T. Want a laugh? Put Rotella-T synthetic on a large screwdriver's blade, then try to pick it up (by the blade) with finger and thumb.

You'll get a grip on it eventually.

Albertj

My $.02:

Traditionally, and with traditional oils, I've always shied away from using thinner oils. I realize that we ALL are very attentive to oil changes, but as the special "reality-reversing" additives in a 5W-30 get worn out, you eventually end up with straight 5 WT...

Synthetic multi-weights are probably better in this regard. I hope so, because I refilled last time with the new 15,000-mile Castrol Edge, and with the larger & superior WIX filter I switched to, I plan to leave it in for 10,000 miles...


Albert: I didn't even realize that the HD Delo 400 & Rotella-T had come out with synthetics. Why don't you use straight Rotella, is it that much more than Mobil 1?

10,000 miles? Isn\'t that about 5,000 miles too much?! Even on synthetic it seems excessive. I could care less what manufacturers claim, I could never go that long.

LOL albertj, like tryin to grab a slippery nipple?

I run Mobil1 5w30 year round. Have been for years and my original block is still running strong with 150K on it now. (went to somebody else's car at 140K). I used to change every 5000 but recently changed to 10000. I use Mobil1 oil filters too (larger capacity filter- look up filter for a 4.3 S10 to get the same thread and diameter but a longer filter).

Granted our summers aren't as hot as southern summers. If I lived in Arizona or Texas I would probably use 10w30 in the summer months.

Abaddon wrote:

10,000 miles? Isn\'t that about 5,000 miles too much?! Even on synthetic it seems excessive. I could care less what manufacturers claim, I could never go that long.

Well, Mobil has been selling different "mileage-grades" of their synthetic and syn-blends for a long time, and I haven't seen any class action suits... I ran their 7500-mile blend last time for 5,000 miles, the same "safety/cynicism ratio" as running 10 on the 15. Besides, if it doesn't last longer, why pay the price for the synthetic?

I admit that there should be a warning that no filter is going to go 15,000 miles, but since my WIX filter has over twice the filtering media as some of the stock filters, I figure I can probably go 10,000 on both the oil and filter. Else, I'll throw a new filter on it when it's ready for an extra quart of oil at 4,000 miles.

eh, I just can't do it . But, I've been workin in a shop for a long time, and I change my oil when I get bored.....maybe just cause I can.

Eldo wrote:

My $.02:

Traditionally, and with traditional oils, I've always shied away from using thinner oils. I realize that we ALL are very attentive to oil changes, but as the special "reality-reversing" additives in a 5W-30 get worn out, you eventually end up with straight 5 WT...

Synthetic multi-weights are probably better in this regard. I hope so, because I refilled last time with the new 15,000-mile Castrol Edge, and with the larger & superior WIX filter I switched to, I plan to leave it in for 10,000 miles...


Albert: I didn't even realize that the HD Delo 400 & Rotella-T had come out with synthetics. Why don't you use straight Rotella, is it that much more than Mobil 1?

"reality-reversing" additives in a 5W-30 get worn out, you eventually
end up with straight 5 WT...

I know what your saying but I'm not sure I'm on the same page as you on this one. Unless there is some lab testing to back it up.
And your follow up statement of buying and installing some synthetic oil that the manufacturer has rated to 15,000 miles, but to be cautious you'll change it at 10,000 miles.
Why use the oil if your not comfortable to it's rated potential.?
Hell, I know bringing up subjects of oil and what type and grade to use can be worse than talking politics or religion in a bar. But, while we are here, what does the 1/2 qt of Rotella do for your engine other than mwake you feel better. Nothing wrong with that, don't get me wrong.
I know a guy who has been using Castrol 20w50 in his 1972 Harley since they came out with this oil and became accessible to him, no matter where he was in the country.
Everyone told him he would ruin his engine as the factory spec's on a 72 HD at the time was straight 50 or 60 weight in the summer.
His first preventive maintenance teardown at a little over 100,000 miles showed no excessive wear, just normal wear and tear, to the point where the Harley dealership's mechanic that did the first overhaul was so impressed with the condition of the engine he almost called my buddy a liar for saying he ran automotive multi-weight for over 100,000 miles.(He bought the bike new in 72) We took it apart about 5 years ago at the 240,000 mile mark with the same results and still using automotive grade Castrol 20w50. Based on the amount of miles on this bike you can tell he's a long distance rider.
But I digress, can't you say to some degree that oil is oil, as long as your following the manufactures recommendation for weight of oil and time intervals for changes.
Don't you think your safe with what is recommended for viscosity and time change intervals.?
I put Synthetic oil in my car for the first time this last oil change and will keep my eye on it as well as have lab analysis done because I to am from the old school of changing oil every 3,000 miles.

Quote :

eh, I just can't do it. But, I've been workin in a shop for a long time, and I change my oil when I get bored.....maybe just cause I can.

When I had the run of the family shop with a rack (and with the family bar next door!) I always changed my oil between
3 & 4K miles, too. A tall Myer's & Coke was the perfect timer for letting the old oil drain out of the pan & the filter adapter.

Since my brother closed the place in 2001, I find it much more difficult to get motivated to get under the car...
And of course, besides the synthetics, all motor oils keep moving farther down the C and S grading scales - when I
first started changing oil, it was CC/CD and SD/SE... and gas was 68 cents/gallon

Eldo wrote:

When I had the run of the family shop with a rack (and with the family bar next door!) I always changed my oil between 3 & 4K miles, too. A tall Myer's & Coke was the perfect timer for letting the old oil drain out of the pan & the filter adapter.

I truly wish i grew up with that available to me.
So, you started learning about cars while you were still peeing in your pants. Cool.

Eldo wrote:

My $.02:

Traditionally, and with traditional oils, I've always shied away from using thinner oils. I realize that we ALL are very attentive to oil changes, but as the special "reality-reversing" additives in a 5W-30 get worn out, you eventually end up with straight 5 WT...

Synthetic multi-weights are probably better in this regard. I hope so, because I refilled last time with the new 15,000-mile Castrol Edge, and with the larger & superior WIX filter I switched to, I plan to leave it in for 10,000 miles...


Albert: I didn't even realize that the HD Delo 400 & Rotella-T had come out with synthetics. Why don't you use straight Rotella, is it that much more than Mobil 1?

I don't use Rotella synth because in my car it ran past the seals. Big time. Switched back to Mobil-1 *immediately* problem solved. As for price, straight synth Rotella is actually somewhat less than Mobil-1.

I had also tried the WalMart store brand synth, did not like it. When the oil got old, maybe it was my imagination but it seemed to, well, evaporate.

As for the oil change interval, I do mostly highway driving, which stretches out oil life. I change at the first convenient time to do so after ~7000 miles. I burn maybe 1/2 quart between changes. I use Delco, WIX, Champion, Purolator. Not Fram, personal preference.

Albertj

Oh by the way, different cars (same make and model, different vehicle) vary in how the engine is wearing and using oil. I think the only way to really know for sure and set your oil interval correctly would be to use Blackstone or another test lab. See:

http://www.blackstone-labs.com/gas-engine.php

to learn more and see sample reports.

One thing you learn - for a healthy gas engine wearing normally, synth oil *will* decrease wear as long as you don't change it *too often* - that's right, more frequent changes are *not* usually better.

Albertj

Highway driving is a different ball game.....oil definitely lasts into extra innings in that game.

Abaddon wrote:

Highway driving is a different ball game.....oil definitely lasts into extra innings in that game.

Yep, essentially all my driving is highway.

Albertj

Tell me this: Do these 10k-15k mile oil bottles include disclaimers regarding your type of driving? Like the owners manual has regular and severe duty maintenance schedules for oild changes. I'd think that would also apply to one of these hi mile oils.

I have a hint of coolant in my oil when I change at 3500. Barely higher than average. Blackstone says 3500 miles is as long as they'd recommend going considering that analysis. I'm running Mobil 1 5W30 these days. Being in Fargo, I'd use 0W30 in winter but it's not usually on the shelf around here. Just turned 130k on the odo, don't burn any oil between changes.

albertj wrote:

One thing you learn - for a healthy gas engine wearing normally, synth oil *will* decrease wear as long as you don't change it *too often* - that's right, more frequent changes are *not* usually better. Albertj

That's interesting....Do you know why or is it just from experience that you now this.
As I mentioned, this last oil change for me was the first time I've put Synthetic in any car I've ever owned.
I do mostly country road driving and highway. No in between.

Albert, please explain why more frequent syth oil changes would result in more wear than changing less frequently. I can't imagine why that would be.

1998 Riv wrote:

I have a hint of coolant in my oil when I change at 3500. Barely higher than average. Blackstone says 3500 miles is as long as they'd recommend going considering that analysis.

Why wouldn't you eliminate the coolant issue.?
Average is 0%.

Albert,
Does the oil go through some sort of break in procedure and then provide better lubricity during it's mid-life,?
Sounds very counter intuitive to me.

Rickw wrote:

1998 Riv wrote:

I have a hint of coolant in my oil when I change at 3500. Barely higher than average. Blackstone says 3500 miles is as long as they'd recommend going considering that analysis.

Why wouldn't you eliminate the coolant issue.?

Lack of free time to do it myself. The parts are in the garage waiting, since oh about 1 1/2 yrs ago. Blackstone was not exactly worried about the level they found, esp since there is no measurable drop in my coolant levels over time.

Then why use Synthetic that you have to change every 3500 miles.?

1998 riv wrote:Albert, please explain why more frequent syth oil changes would result in more wear than changing less frequently. I can't imagine why that would be.


the tension is killing me......................

1998 Riv wrote:

Albert, please explain why more frequent syth oil changes would result in more wear than changing less frequently. I can't imagine why that would be.

In a nutshell, a series of analyses in an engine using synth oil showed higher wear in the first few weeks after each oil change. Link:

http://neptune.spacebears.com/cars/stories/oil-life.html

The link goes to "Paradise Garage" which did a reasonably controlled longitudinal study.

In a nutshell, what they found was that just after each oil change, wear metals in the oil spiked up then levelled off for ~10,000 miles, then started creeping up again (time for another oil change, natch). Here is their longitudinal study of Mobil-1. Using Blackstone Labs for testing. They saw ~14,000 miles before need to change.

http://neptune.spacebears.com/cars/stories/mobil1.html

If you have not seen the study before and you have a little time on your hands, have a look. It is reasonably well written and informative. Remember, it is a study not a clinical trial so read carefully and remember, your results may (will) vary (that's why you need to test for yourself most likely).

Albertj

1998 Riv wrote:

Tell me this: Do these 10k-15k mile oil bottles include disclaimers regarding your type of driving? Like the owners manual has regular and severe duty maintenance schedules for oild changes. I'd think that would also apply to one of these hi mile oils.

I have a hint of coolant in my oil when I change at 3500. Barely higher than average. Blackstone says 3500 miles is as long as they'd recommend going considering that analysis. I\'m running Mobil 1 5W30 these days. Being in Fargo, I'd use 0W30 in winter but it\'s not usually on the shelf around here. Just turned 130k on the odo, don't burn any oil between changes.

No, no disclaimers. But that's why I wrote that if you really wanna know you really oughta test. Although I admit I did not so state so directly as I just did.

If I changed my oil every 3 - 4,000 miles not only would I not have any real loss, it\'d most likely still be translucent (not transparent like new) golden on the dipstick.

If you have coolant in your oil, that does mean there is a gasket somewhere you need to replace?!? Your mileage on an oil change will be lower than that of someone who does not have coolant in oil, right?

Albertj

Rickw wrote:

Then why use Synthetic that you have to change every 3500 miles.?

I find the engine turns over more easily in winter temps with synth oil. I see winter morning temps in the minus 30's at times. And it sits outside at work all day.