Is it true that dino oil is capable of up to 7500 miles? I thought it was only good to 3000 or 4000 miles because of the relatively short lifespan of the base oil and additive package.Someone please enlighten me.

 

I read a Quaker State brochure years ago (15 or so) that said that "dino" oils, used in typical or "average" situations, "started" to break-down, and if memory serves me (which it occassionally does), they were speaking of the additives moreso than the actual petrol, anyway, the additive pkg. begins to deplete at about 1000 - 1,500 miles, and by 3000 miles it was time to change (hence the massive advertising along these lines). In a perfect world (i.e. - "ideal" starting and driving scenario) 70 degree or warmer starts, motoring long enough to burn off all condensation, acids, etc., and then if one was to drive beyond that COMPLETE burn-off period, have the weather cool down, um, say, 25 - 30 degrees (wouldn't that be nice!) for the duration of their trip - and then, have it be 70 or warmer again when you have to start the process all over again (my dream world! - oh, I forgot the need to eliminate stop signs, stop lights and MOST [somewhere between 60 - 85%) of the other "drivers" on the road). I think you get the picture. I TRY to split the difference (though it is difficult) depending on the seasons and the driving I've DONE on any particular crankcase fill I've been toting around. Typically, w\dino, I go 2-3000 miles winter and summer and 3-5,000 spring and fall. It's worked for me for over 20 years (more like 25), and I am comfortable with it. Of course EVERYTHING is subject to change, given all the potential variables - but this is just "Glenn's" rule of thumb. Hope I helped, at least a little. Take care . . .

 

I agree with Ford's intervals of 5,000 miles for those of us who drive alot on the highway and 3,000 miles for short trips and stop n' go driving. I really can't see ever going past 5,000 miles. I think you'd be better off changing oil every 3K with an inexpensive API GF-3 oil than pushing past 5K with even a synthetic. Just my .02

 

GM allows 7,500 or one year for "normal" driving on light-duty emmissions vehicles (under 8500lb GVW) and 6000 miles or six months for heavy-duty ones. BMW goes up to 10,000 with synthetic, using the engine computer to determine the exact interval based on hours, rpm and temperature.

Look at the oil testing results in this forum with Formula Shell. Viscosity within grade and no significant depletion of additives after 3000 miles. It could go a lot further.

I have a sample of 5000 mile dino out for testing now. The results will tell me if I am going too far. I doubt it.

Jim

 

my 2 cents...
based on my 3000 mile drain sample and test of the Shell 10W-30, there was basically NO change in anything; viscosity, wear metals and additive package were all pretty much the same as the control sample I sent in.
I too have heard and read info about the dino oil "breaking down" and the additive package "breaking down", but didn't see that happen.
I know it's just one test, but I'm comfortable with my conclusion based on my test: In many (most?) cases, oil drained and replaced at 3,000 miles has probably not seen much more than 1/2 its useful service life.
I'm still planning to do a 5,000 mile test of the Shell 10W-30 to see what that shows.
Brian A

 

Don't forget the conditions in which "they" say 7,500 mile oil are OK. Normal driving, whatever that is. What about everyone does -- stop and go driving, short trips less than 15 miles where the engine never warms up, that's under the heading "severe service" -- look it up in the operator's manual. If you are driving on the Interstate all the time, I'd go with the longer drain interval.

Gravel Roads. -- I remember reading Bob Sikorsky's book "Drive it Forever" I think it was (he's an SAE oil guru, or something) and he sez gravel roads are like death to car and truck engines. He went so far as to say in the book to change the oil immediately if you so much as drive down a gravel road, heh. Most of us don't have that kind of dough but his oil analysis after driving through gravel dust was pretty convincing. Silicon (sand) levels really spiked up. I don't drive on gravel if I can help it and sure don't eat anybodies dust.

The number one cause of bearing failure is dirt. Plain ole' crud. Doesn't matter if you're using Space Shuttle approved NASA 30 weight or Quick-Mart smooth flow at .69c a quart -- if you leave that stuff in the crankcase too long it gets loaded up with dirt and carbon and fuel and golly knows what and sooner or later the filter gets plugged. Basically, you're running an abrasive slurry over your finely machined parts inside the engine. Rub your fingers with a bit of that nasty stuff off the dipstick -- feels gritty, don't it? Filters used to be an "option" -- they aren't any more for good reason. Also the additive package gets used up and part of the oil volatiles burn off while the condensation and all the other crap start to form acids.

My guess is people go overboard and probably 'waste' oil changes but oil is cheaper than an engine rebuild every time. The oil filter is at least as important as the oil - maybe more - so don't buy el cheapo filters because the extended drain intervals are only possible if using good filters -- Motorcraft, WIX/NAPA GOLD etc. and if you can't swing the oil change itself for whatever reason at least swap out the filter for a new one. I don't think there's anyway to tell if a filter has gone into bypass mode but you don't want that at all. I don't run synthetic nor the no-name stuff but keep the oil changed regular like.



Keep 'er between the ditches.

 

My driving is "normal" based on the owners manual definition. Police and Taxi, door to door delivery with extended idling, frequent towing, or under ten mile trips in freezing weather are listed as "severe" service. I do none of those. As much as the quick lube places want us to spend more money, stop and go driving with a warmed-up engine is normal service.
>
>Gravel Roads. -- I remember reading Bob Sikorsky's book
>"Drive it Forever" I think it was (he's an SAE oil guru, or
>something) and he sez gravel roads are like death to car and
>truck engines.

When was this book published, 1960? Trucks from that era had open breather systems and some had no oil filter as well as a "brillo pad" air filter. Look at the closed PCV system and and air intake systems on modern fuel injected vehicles. Unless you leave a hose disconnected, or remove filter elements, there is no way for dirt to get in. Oil on the dipstick has never felt "gritty" to me.

Jim

 

[updated:LAST EDITED ON 30-Aug-02 AT 09:44 PM (EST)]No, it was written in the 1990's. Figured the same thing -- no way for dust particles to get inside w/ a good filter and all that. But... oil analysis doesn't lie -- in any case, gravel roads and dusty environments -- oil change requirements are different, no matter what.

As far as the grittiness -- try leaving the oil and filter in your rig on a semi-permanent basis like I've seen so many people do -- heh.. You'll see what I mean.





Keep 'er between the ditches.