3k Mile Oil Replacement A Myth?!?

[Artillery129]

Lol I change my oil every 10k miles full synthetic, it makes much more sense than 3000 miles basic oil, you don't need 3,000 miles changes, this is how they have been pumping money out of people for a long time

[Poochmike]

I'm curious if any of you guys have done any oil analysis? I have used Blackstone as cited in the article in the hope of pinning down a proper oil change interval. Using full synthetic, they still suggest my oil changes be performed every 2,500 miles or so because of increased lead content in my oil (they say from bearings). I have shown my reports to Dr. Dave, the resident oil expert, and he was not concerned with the lead numbers and we are currently trying a longer interval to see how the numbers change. Here is my latest report:


I would highly suggest doing a series of analysis, they are very useful.

[Reboticon]

Originally Posted by Poochmike

I'm curious if any of you guys have done any oil analysis? I have used Blackstone as cited in the article in the hope of pinning down a proper oil change interval. Using full synthetic, they still suggest my oil changes be performed every 2,500 miles or so because of increased lead content in my oil (they say from bearings). I have shown my reports to Dr. Dave, the resident oil expert, and he was not concerned with the lead numbers and we are currently trying a longer interval to see how the numbers change. Here is my latest report:
I would highly suggest doing a series of analysis, they are very useful.

You've touched upon one of the things about the Legend that makes it last so long. The Rod Bearings DO contain Pb (lead) unlike most cars during that era. That is why we almost NEVER see rod bearings go bad.

Another huge factor is the design of the oiling system. The legend (like all hondas and toyotas) spins the oil pump with the actual crankshaft itself, instead of through a coupling device that wears out over time. ( I had an oil pump drive go out in a 5.0HO ford 3 miles from home. There is nothing worse than all the sudden having 0 oil pressure). On the other hand, a LOT of v-8s oil "backwards." MOPAR v-8s and BBF 385 series (429/460) are two examples of this I can provide. Instead of lubricating the main bearings and the rod bearings FIRST, it lubricates the top end, and THEN lubricates the bottom end. So the bottom end has zero oil pressure until the top end is pressurized.

Over time, crud builds up in these passages, and eventually the bottom end is completely starved for oil.

also, if you have a 3.0 or 3.3L dodge, you should change every 3K miles because those things are notorious for the above mentioned problem.

[MD_LegendLS_90]

Originally Posted by Reboticon

also, if you have a 3.0 or 3.3L dodge, you should change every 3K miles because those things are notorious for the above mentioned problem.

More the 3.0L then the 3.3L/3.8L, but still, ya. Chryslers are garage queens sometimes. The A604 tranny is the worst.

I use Castrol GTX HM and change it when I can't see through it anymore Roughly that's every 3k miles for me. The only car I've owned that didn't need frequent oil changes was my Mercedes, which was every 10k or so. Damn car made me nervous like that ...

[Grumpy]

3k mile multi-viscosity oil changes are a waste in any healthy, clean burning automotive engine. Full stop. 3k mile synthetic changes are idiotic. Full stop.

'Fresh' conventional oil actually lubricates better after it's been 'worn in' for a thousand-ish miles...so by changing every 3k you're actually short-changing yourself the sweet spot in the oil's ability to lubricate to its best ability. This is due to the behavior of the friction modifiers that make multi-viscosity (temperature dependent) oils possible.

[Reboticon]

Originally Posted by MD_LegendLS_90

More the 3.0L then the 3.3L/3.8L, but still, ya. Chryslers are garage queens sometimes. The A604 tranny is the worst.

I use Castrol GTX HM and change it when I can't see through it anymore Roughly that's every 3k miles for me. The only car I've owned that didn't need frequent oil changes was my Mercedes, which was every 10k or so. Damn car made me nervous like that ...

Ah, Yeah I couldnt remember if it was the 3.0 or the 3.3 because I wont touch a dodge with someone elses hands, but I remembered one of them was just terrible.

Originally Posted by Grumpy

3k mile multi-viscosity oil changes are a waste in any healthy, clean burning automotive engine. Full stop. 3k mile synthetic changes are idiotic. Full stop.

keywords for some of us

[MD_LegendLS_90]

The thing to remember with Chrysler is knowing who made the engines. Mitsubishi made most of the engines that were 3.0L and smaller. Chrysler made the 3.3L/3.8L V6s (one essentially being more bored out than the other), and those blocks tended to be more reliable. Just don't try to overpower them with mods, or you'll blow out the bottom end, lol! The 3.0L Mitsubishi motor is the biggest piece of crap ever installed in a car.

Similarly, the 3800 series V6 by Buick is probably the most reliable domestic block on the market. In the case of my old Buick, however, it had a Chevy-built 2.8L V6 under the hood. This is a vastly different motor than the one in the trucks and RWD cars. The one in my car was reputed to be one of the worst V6s put in a Buick, the prime reason it didn't make the 1990 line-up.

The only Buick motor to watch out for that I know of is the earlier 3.8L V6 (NOT the 3800 series), which had, wait for it G2 people...

head gasket failures

[89HondaLegend]

I do 3K oil changes on my Legends and my sisters Prelude.
My parents '05 Accord get's oil changes every 5K.

When it comes time to change the oil in all of these vehicles, the oil is dirty, which I would assume means that it has been doing its job of lubricating, cleaning and capturing dirty particles and is ready to be changed. Ofcourse gauging the oil by colour is by no means scientific, I just couldn't keep driving around with my oil going from a dirty brown colour to a dirty black.

I agree that in a 'clean burning' engine, oil changes shouldn't be needed more than every 5K. In fact if I spent a little bit more money on synthetic oils I would definetely let them run to 5K no less anything up to 7500 Miles, however I still wouldn't feel comfortable going past 7500 Miles.

EDIT: I thought it was quite funny to go through the recommended oil change list and find that every American listed vehicle (aside from a few) still require 3K oil changes

[Geneva_Jee]

I change my oil every 5k with Mobil1 full-synth....well atleast I plan to do a 5k interval, I've only had the car for 4.5k so far

[Nino418]

with the way i drive... i should change my oil every time i get gas....






But its always 3000 miles to 3500 for me.