Dinomon

The last time I done oil change was last September 2006 and since my last oil change, I have had only 4000 miles in last 9 months, still 1000 miles more to go for next oil change. Is it okay for the car/engine? Any opinion is greatly appreciated.

VroomVroom

I'll take a wild guess that opinions on this will be all over the map. Personally, I'd change the oil. I drive ridiculous miles so time is never really a factor for me, but I probably wouldn't keep it in there longer than six months.

The G Man

Oil change is based on mileage and time, 5000 miles or every 6 months, which ever comes first. I would change your oil every 6 months.

jack19446

To keep your warranty in effect, you are required (by Lexus) to get the oil changed every six months, regardless of mileage. My dealer told me that at six months + one day, the warranty is void.

TunedRX300

If you use dino oil, 5K is too long on 3mz-fe engines, these engines chew up oil the same way its older sibling sludge prone 1mz-fe.
Lexus put in time because machine operating time is hard to track...it is a conveniant way to cover those short trips with long idles.
But Lexus typically don't tell you why, just scare you off with void of warranty, ask the dealer if you just change oil, went away for a long business trip but park the car for 6 months in your covered garage, would you required to dump that virgin oil?

biff44

I think he was doing that to scare you. That certainly would not hold up in court, and he knows it!

salimshah

There are two problems with low usage:

1. The gravity affect that pulls the oil into the pan and the things at the top get dry and when you run the engine (after long time) there is no oil to lubricate till the pump catches up.

2. Due to combustion, the oil starts becoming corrosive. The only way to reduce this corrosiveness is to replace oil.

If you drain and fill and leave the RX in garge then you need to only worry about item 1 above.

Salim

mandyfig

Hence you need to run the engine every couple of weeks, as stated above, you need the oil on the friction surfaces.

TunedRX300

ZDDP is a common additive in almost every engine oil to offer some protection during dry startups. Here is a link that explains a little about current and future additives
http://utamagazine.uta.edu/fall_2001/discoveries.html

Actually Slick 50 was found false advertizing in a court when it claims engine oils can not offer startup protection. The reason? The commonly used ZDDP.

Even if ZDDP won't stay effective for a long time such as 6 months, changing oil won't matter since fresh oil will go straight to the pan, no oil will get to those vital engine parts for lubrication.

shikbas

So ,what about synthetic oil

jim256

synthetic??? ...no matter the type of oil, as long as it meets the Lexus standard (SJ, I believe, or later) you have to do the 5k/6 month changes to satisfy the warranty during the warranty period, although I am sure nobody will make an issue out of 5 k changes as long as you do it within 6-12 months.

kingofire

Ummm, soooooo, what is going to happen to all these people with the 3MZFE engines that are oblivious to this and just follow the maintenance schedule in their owners manual and go get their oil changed every 5K miles? Dont you think lexus engineers might have done some 5k tests on this engine and sent the oil for analysis to make sure the oil can handle this?

salimshah

The problem is with peopl who do not follow even @ 5k.

Salim

TunedRX300

Salim is right, folks don't follow 5K rule since most don't fall into Lexus defined "severe" condition.
What happens is within warranty, if there is an engine failure, dealership book the repair profit at the expense of Lexus corporate. For us consumers, we care about what happens after the power train (or in 1mz-fe's case, 8 year sludge) warranty expires.

There is no other way to prevent huge out of pocket repair $: either shorten the change interval for dino or use better and more expensive pure synthetic oils. You are very smart to use used oil analysis, that is the ultimate accurate and scientific way to know what is the optimal change interval for the oil and driving condition for you.

For other folks that do not believe when I say 5K on dino, 7.5K on synthetic is too long for 3mz-fe. This RX330 owner used Mobil 1 5w-30 Extended Performance oil that is supposed to go 15K miles (e.g. beefier additives pack than the regular Mobil 1). He barely get out of 7-8K out of the oil. If he used the Mobil 1 5w30, oil is depleted before 7k for sure.

http://theoildrop.server101.com/foru...&Number=813317

mandyfig

5K rules! I actually change @ ~4,500 miles or when I am tripping and just want to do some work on the cars.