AlexusAnja

we went to Orlando with ours this past November and went from NJ to FL (Disney) in 18 hours with two stops. Sooooooooo comfortable.

I6turbo

iTrader: (1)

How many miles do your vehicles generally have on them when you sell and replace with another vehicle?

I6turbo

iTrader: (1)

I've sent samples to Blackstone Labs (one of the most widely used) and it's pretty interesting to review the results. It's pretty clear that the type and severity of use is in fact a HUGE factor in how long an oil holds up. My Supra, for example, which I always keep at a boost setting that will produce ~900 HP and always on leaded race fuel, often needs its synthetic oil changed at <500 miles according to analysis. And I have no reason to doubt it -- the oil certainly looks and smells like it needs changing compared to what you'd see in a "normal" engine.

It's also interesting that Blackstone, people who make their living analyzing oils, say this in their FAQ:
What's the best oil to use?
Ah, the million dollar question. We are an independent lab, so we don't make recommendations. It has been our experience that oil is oil, and either petroleum or synthetic-based oil will work well for just about any engine.

Come on, you're holding out on me. I should use synthetic, right?
Buddy, you should use whatever you want. Synthetic oil won't guarantee a longer engine life any more than my eating organic food will guarantee I'll live until I'm 90. We here at Blackstone generally use regular petroleum-based oil because honestly, it works just as well for us.

DNC

My work vehicles will have between 200K and 300K. My personal use vehicles will have anywhere from 50K to 200K.

LS430inDE.

If that's the case then it's my misunderstanding, but how I read your previous quote, that it was what you were paying the dealer.

Also..fwiw...it's the 3month/3k mile change cycle that I'm on. As I have a company provided vehicle that I drive M-F, there are many instances where I don't drive or start the LS for several days.

Then...whenever I DO drive it, it is almost always less than a 15 minute drive to wherever my destination is...so the LS probably doesn't fully warm up to the point of vaporizing any potential moisture/condensation out of the oil, etc!

Mileage isn't the only determining factor in determining if you oil is still "fresh" or not. We all should know NOT driving, or driving the vehicle for so short of a time (less than 15mins) the engine doesn't fully warm up, juices flowing, etc. can be just as detrimental to the degradation to the lubrication/protection characteristics of the oil.

There will definitely be instances where I end up changing the oil at the 3 MONTH interval, and not 3k miles...especially now, since I still have my 3.5RL (that you guys love), and won't rack up miles as quickly on the LS (or RL for that matter). I don't drive the LS every day..sometimes it's not even started for 3 days!

Last, but not least....my GOAL is set for 3mo/3k miles...but it usually ends up over it because I'm busy that weekend, it's raining, etc.

So...that all being said, I guess you synthetic freaks are now going to say that synthetic only "breaks down" when it's used (mileage), otherwise, it can sit in an engine for years without breaking down or losing its protective properties?

DNC

I'm a synethetic freak but I agree with the frequent changes. Years ago a Mobil engineer told me to change the oil every 6 months in my vehicles that I don't drive often. I am of the impression oil sitting in a car that isn't being driven often still absorbs moisture just like brake fluid; depending on conditions in your area.

jayclapp

They don't put expiration dates on the oil that you buy do they? Oil is millions of year old and doesn't necessarily "break down" with time. Synthetic oil is even better. Gas turbines are know for their long life in comparison to recip engines and they always use synthetic oil (they develop their oil life by taking oil samples to determine contaminates and metal particles during the development stage of the gas turbine). I wouldn't even think of using anything other than a synthetic oil. Just my opinion and experience as a retired gas turbine engineer.

DNC

Oil is in air tight containers before being used. After that it's in an engine where it is exposed to contaminates. I guess it depends on your definition of "break down", but yes oil does break down or become contaminated.
I really like synthetic oils too.