Changing oil every 3k miles. Are people wasting money?

[GotTurbos?]

I remember hearing that Jdub said that changing your oil every 3k miles was a waste of oil. Could you explain to all of us why this is the case?

-Matt

 

[billwert]

IDK about everyone else but I start losing oil pressure at about 3k miles. Maybe somethings wrong too? Using Castrol High Mileage 10W30 non-synthetic.

 

[Slow_Sc3]

if you love engine sludge in your motor why ever change the oil?

the 1jz that i got, the person in japan never did any oil changes and oil cloged the feed for the turbo and the shaft for the turbo snaped into two peice's, the rest of the motor looked like crap under the valve covers.

 

[jdub]

Matt - This SAE paper explains it:

"Title: Extended Oil Drain Intervals - Conservation of Resources Or Reduction of Engine Life (Part Ii)"
After reading that you may never change your oil again at even 10,000 miles!

There are millions of miles of oil analysis that not only prove short duration changes increase wear but also result in a lack of additive activation in the motor. If you own a Jiffy Lube then I would expect you to subscribe to the "3,000 mile Mentality" myth.

Oil additives are activated by heat and pressure. Due to the additives having to hold up over time i.e. longer than 10,000 miles the formulations take a certain period of time to become active in protecting the motor. Draining the oil at lets say 3,000 miles simply means the additives have just become active at the point you are draining your oil! In other words you are increasing wear by about 500% doing 3,000 mile drain intervals!

Oils that carry the extended drain ratings such as 506.01, 507.00 etc mean that the additives are formulated to remain active for periods up to 2 years, 40,000 kms or 640 hours of usage. Oils like Mobil 1 0w40 are formulated to withstand 400F sump temps WITHOUT breaking down and losing viscosity. Furthermore the oils cannot break down due to the PAO makeup of the oil. These oils do not rely on elastomers like the conventional oils do. This means that the oil can fully protect your motor at any temperature without the concern of thermal break-down and thinning out of grade.

If you doubt the 10K oil change intervals perform an oil sample at 1,000 miles. Most cars with a fresh sump of oil will peak out at the 1,000 mile mark. After that the wear metals may increase by only 5-10% over the course of 10,000 miles! Nearly 90% of the engine wear occurs in the first 1,000 miles on an oil change! Increasing oil change frequency increases the duration your engine spends in the activation period of the additives and greatly increases the damage in your motor from failing to follow the guidelines of the manufacturer.

Just looking at iron in a VW motor typical readings are around 20-35 ppm after 15,000 miles of use maximum on a motor that has more than 60,000 miles. The oil filter is not capable of filtering this much metal simply because the wear metals are so small they can't be filtered from the oil. Also because there is so little wear metal you do not get wear as a result of the metal being suspended in the oil.

Dispersant's require time to bond to the wear metals and byproducts in your engine oil. As byproducts such as soot (gasoline or diesel make soot just different sizes which discolor the oil) are created additives coat them and prevent them from clumping and becoming larger. Typical soot particles in diesel oil are in the nanometer range in terms of size 10 times smaller than what any bypass filter can even capture which is rated at 2 microns absolute. Your oil filter in your motor is rated at capturing particles in the 7 micron range with only a 75% first pass rating...Bottom line is your car would last forever if you change the oil every 20,000 miles and NEVER replace the oil filter simply because your motor is not making enough metal or by-products to ever get captured! Oils especially those for diesels can handle upwards of 8% soot, that my friend is a LOT of soot! To put that in perspective a typical motor after 25,000 miles without an oil change or filter change will only have 1% soot in the oil. This oil will appear tar black yet the oil still has 80% of its rated levels of protection remaining!

Most oils are limited by time in the sump rather than miles due to sulfur in the fuel. Most gasoline motors can safely go 2 years between changes when using quality oils formulated for extended drains such as Mobil 1 0w40 and Truck and SUV 5w40. These oils along with those sold as VOW 506.01 have very high TBN ratings that neutralize acid formation for upwards of two years (1 year in diesels due to higher sulfur content which causes the acids).

Here's the deal, forget the myths about frequent oil changes and basing your perceptions on how the oil looks. The best advice is use a quality oil and drain it at the specified interval. The worst thing you can do to a modern car is over maintain it, yes this is possible due to the very specific regimen that VW engineers figured out to keep your car running at peak performance with maximum durability.

It's really simple...the oil change places out there make $$$ by you coming in every 2 months. Any decent dino oil will go 5000 miles. A PAO or ester based synthetic, 8000 miles easy (just change the filter at 4K). If you do analysis, you can go even longer. Of course this assumes your motor is in good shape...i.e you don't have dilution or contamination issues.

And read JJ's recent post (and the link he included):
http://www.supramania.com/forums/showpost.php?p=994751&postcount=103

IDK about everyone else but I start losing oil pressure at about 3k miles. Maybe somethings wrong too? Using Castrol High Mileage 10W30 non-synthetic.

Bill - if you're losing oil pressure at 3000 miles, it is not likely it is due to the oil. You'll see some of the thicker multigrades drop in viscosity as it is heat cycled over time. This is due to the extensive use of viscosity improvers required to achieve the wide cold/hot viscosity spread. The oil will migrate to the native viscosity of the base stock. You should not be seeing that in a 10W-30...perhaps it's time to try another oil.

if you love engine sludge in your motor why ever change the oil?

the 1jz that i got, the person in japan never did any oil changes and oil cloged the feed for the turbo and the shaft for the turbo snaped into two peice's, the rest of the motor looked like crap under the valve covers.

Slow - this comment is so full of innuendo and misrepresentation it's almost not even worth responding to. To compare a 1JZ engine that you have NFI what the real history was and have NFI how long it sat in the weather before you got it, to a motor that is run (and maintained) is just ludicrous. You bought a junkyard motor and that is precisely what you got. This sort of rationalization is exactly why you hear the crap that gets bounced around about motor oil. It's based on what you *think* happened...pure BS

 

[Nick M]

I did 3/3000...until I went to school and learned different.

http://www.supramania.com/forums/showthread.php?t=23917

Ultimately, the best time to change it is when an oil analysis has been done. And if you don't do that, use the factory intervals.

 

[johnathan1]

I thought it was odd that Toyota says to change the engine oil every 2500 miles on the air filter housing...but when I took my car to the dealer to have the oil changed, the sticker they put in the windshield says to bring it back in 6000 miles? Maybe oils in the 80's didn't last as long as newer ones?

 

[Poodles]

I thought it was odd that Toyota says to change the engine oil every 2500 miles on the air filter housing...but when I took my car to the dealer to have the oil changed, the sticker they put in the windshield says to bring it back in 6000 miles? Maybe oils in the 80's didn't last as long as newer ones?

BINGO!

Hence why the whole debate about going to a 40w oil as said in the owner's manual that is horribly old and outdated info.

Modern oils (even cheap ones) will out perform any of the oils from back then...

 

[billwert]

I think my problem with losing oil pressure is coming from leaky valve stem seals. So i'm actually losing oil; prolly not the 10W-30's fault. My fault for not having a valve job done.

 

[jdub]

Valve seals will not cause a pressure loss either...bad seals will cause an oil loss over time though. You need to look for another cause...the relief valve in the stock filter head is where I would start.

 

[billwert]

Are you talking about the Oil filter itself? Or what the filter attaches to?

 

[jdub]

...the relief valve in the stock filter head is where I would start.

Thought I was pretty clear

Personally, I would get rid of it completely and switch to a full flow cooler/remote filter circuit.

 

[billwert]

Sorry; ya gotta remember i'm only 19:3d_frown: and still learning. Thanks Bill.

 

[jdub]

Good luck with your problem...hope you solve it.
I will watch with interest.

Thread closed.