wots the best oil to use???

[sillbeers15]

Nicely,

It is great to know that you stand firm by your believe.

As for me, I've seen too much of uncertainty in the engineering field in my career, especially regarding premature failures that cannot be explained.

I have a W124 in my family for 19 years, it has been feed on mobil 1 syn lub (changed every 10000km) and mercedes coolant since day1. 270000km later no. 1 cylinder lost compression. The engine was striped for a rebuilt. The internals of the head and chambers were in perfect condition but the culprit that caused cylinder 1 to loose compression was a bend valve. How and why beats me?

For my 4 months old Murano, I service it the same way as above.

It is temperature and pressure that kills a combustion engine. We all know that it just takes a few seconds of detonation to bust a motor, so there is no certainty that the oil will not break down prematurely under higher temperature environment of a boosted engine. I guess that race teams strip and rebuilt engines after every race for the same reason of not taking any risk, right?

It just does not make sense for many of us to fit oversize radiators and oil coolers as insurance to manage the engine temperature, yet take the risk over saving a few dollars on oil usage.

As for a 1.2bar boosted turbocharged SR20DET in my s15 that has a full aluminium head + block w/o steel sleve, I don't take my chances like the above.

 

[gunner93]

The subject of lube is close to my heart. For fully syn I make it a point to find out what group of oil the blender uses. Note that some brands drop down to group III and legally calls it fully synthetic (which is ok if the price is right). By and large, you know your car best. Use a suitable oil that suits your application and a OCI that will not compromise on your engine's performance and durability.

 

[A'PEXi]

mobil 1, 10w40

 

[Nicely]

Its not a case of standing by my belief. Its a case of standing by the results of laboratory analysis on oil run for 6k miles in engines running standard right though to 1.4 bar level tunes. The analysis shows that fully synth oil which conforms to the required standards shows no signs of breaking down, thinning, nor being contaminated from a healthy SR20DET engine after 6k miles (of daily driving). If an engine is unhealthy, changing the oil every 3k miles isn't going to stop it being contaminated and potentially causing damage.

And what about the oil filter? Do people buy the best oil filters available to ensure maximum flow and filtration, or fit the Nissan original? Surely this would be equally (if not more important) as changing oil every 3k miles? What's the point in changing the oil frequently if the filter is crap at filtering or so restrictive that it seriously effects flow?

 

[moomin]

just like to add, i still agree with nicely, and, just to let you guys know i have changed my oil now, after 8.5k and, the oil i had drained out was not black & mucky like someone had stated, not in the slightest, still perfectly good useable oil. i must admit, i would tend to agree with what nissan say, as at the end of the day, they made the car, not some "mechanic" or "turbo specialist" and also just to add, my car has NOT been serviced every 5 minutes like alot of you guys have done, and is quite a high mileage model standing at 79500 miles and i have absolutely no rattles, crashes, bangs, smoke at all, it has always been absolutely trouble free and is completely smooth. and i do like to put my foot down like the rest of you. so, i think to close, to keep your car healthy, and problem free you should change your oil according to what Nissan say, but, if some people dont want to believe a HUGE car company that has been making turbo's silvia's for 20 years or so, thats there choice.
:rotfl:

 

[Paul D]

Does anyone use an engine flush on oil changes? I used to flush my sr20ve engine every oil change with castrol engine flush and it kept everything like new inside

 

[Nicely]

No, no ,no no, no, no, NO!!!!! :no: Engine flush is the quickest way to destroy your engine. Flush remains in the engine and breaks down the new oil. Best thing is to do a change with some cheap oil (with the old filter on), let the engine tick over for 10-15 minutes, drain and do a normal change with filter and fully synth.

 

[sillbeers15]

Moomin,

If yr S15 is bone stock running no higher than stock boost, then what you said about Nissan advice makes sense. Else just use your brains.

 

[moomin]

crikey its getting really bitchy on here lately!
whats going on!?!?

 

[Nicely]

Its just a difference of opinion

Personally, I'll be going off the evidence I can see gained from specific oil testing, rather than folk-law passed down by third parties who probably haven't actually verified the validity of their advice (I'm meaning all the 'top tuners', not anyone on here ). However, I can understand people being cautious. For years SXOC members insisted that 3k mile oil changes were essential. It wasn't until they saw the results of the oil analyses that they altered that view.

 

[sillbeers15]

Nicely,

In engineering, there is a term call 'safety factor'.

It is good to have emphrical test results. I am sure, the tests were carried out under certain controlled conditions and environment.

In different locations, temperature, humidity, sealevel, types of fuel are all different. Besides, when we tune the rom for optimised performance....we're closer to the edge.

If I were to make a decision on a fleet of company cars....I'm very happy to stick by tests results. Since my S15 is my toy, my passion rules!

 

[Nicely]

The oil tested was mainly from tuned cars, as opposed to mainly standard.

I understand the caution :thumbs:

I do feel that not enough credit is given to just what modern synthetic oils are capable of these days. They are vastly superior to how they were five years ago, let alone nearly ten when many of our cars were produced.