what oil do s15's need?

[BOOSTED]

My service is a while away but I have no idea what oil is in it atm lol

I know you use synthetic but what type?


cheers

 

[DeanS15]

i use millers cfs fully synthetic 5w40, others use different ones but i find this is fine on my car.

 

[BOOSTED]

so probably 0w40, 5w40, 10w40?

 

[DeanS15]

taken from sxoc mate
The manufacturer seems to recommend a range of oils for your cars from 5w to 15w and sae 30 to 50.

Based on regular service intervals and "normal" driving however the best bet with regards to standard cars and UK weather is 10w-40 Semi or Fully Synthetic.

There are always options to consider with regards to "special requirements" if you would like to do this but you'll need further advice and.................I may have further questions for you.

Nissan 200sx (1989-93) API SF
Nissan 200sx (1995-97) API SG
Nissan 200sx (1997-99) API SH

Specs have moved on now so most oils sold today are API SJ/SL

As mentioned above, there are reasons for stepping out of the Manufacturers recommended grade but you should never go too far, 0w might not be good here nor would 60, it's just a step too far.

So, why would you want to do it?

Basically there are advantages here and they are as follows:


5w-40 instead of 10w-40

5w offers better cold start and short journey protection as it's thinner than 10w and remember this is when 70+ percent of the engine wear occurs.


10w-50 instead of 10w-40 - 15w-50 instead of 15w-40

50 offers better protection than 40 when the engine is running hot so if you're doing track days or hard driving you may want to consider this option.

A word of warning about 60 grade

Modern engines do not need a 60 grade, it's really too thick and, even hot-running engines do not need SAE 60 oil these days. (by ‘hot’ I mean 120-130C). SAE 60 is heavier than most SAE 90 gear oils. If an oil is too thick, it de-aerates slowly, leading to cavitation in the oil pump, or the bearings being fed slugs of air along with the oil.

The thickness of the oil will also have an effect on the cars performance.


Synthetic Oils instead of Mineral Oils.

It is a fact that Semi and Fully synthetic oils are better for your car, they flow better when cold and give a greater level of protection when the engine is hot.

It is a fact, not myth that complex engines such as DOHC, Turbocharged, and Supercharged when driven hard will always have a greater degree of protection from a synthetic oil.

A synthetic oil is more robust and will last longer (that's why they cost more) mineral oils need much more frequent oil changes but they are cheaper. Semi-synthetic is to some extent the "middle ground" for pennies more than a good mineral oil.


Ester Synthetic Oils against Normal Synthetic Oils

The oils that give true benefits are ester synthetics (pretty hard to come by as they are expensive to make although Silkolene still does). The reasons for their application in motorsport and the aviation sector are clear:

They assist the additive pack in a motor oil formulation because they are surface-active (electrostatically attracted to metal surfaces), so they help to reduce wear and friction.

They are fluid at very low temperatures and at high temperatures they are very chemically stable and have low volatility (don’t evaporate away).

They also help to prevent hardening and cracking of oil seals at high temperatures.

It should be said that there are three types of synthetic oils on the market and they vary in quality and price the lowest being MC/HC (Molecularly Converted/Hydrocracked) mineral oil, POA's Poly Alpha Olefins and Esters.

 

[Auss15]

Seeing you live in sunny,warm Queensland I would use a synthetic 10w-40w

 

[david]

I used castrol Gtx magnatec 10/40 in all my nissans iv had, great oil :nod:

 

[BOOSTED]

sweet that's what I was using in my old car


now what brand?

I heard royal purple is one of the best

 

[Nicely]

If it was me and just for road use, I'd use some cheap motor factors fully synth which meets the minimum standards. SXOC commissioned professional oil analysis tests (done by Ford's engineering labs) on many different brands (fresh and after 3-9k miles run in various S13 and S14s). They showed no real difference between them and that they would have still been good if run for 9k+ miles. Of course, results would be different if the car is abused on the track.

Of course, like most people, you will probably ignore this and go off what the oil manufacturers tell you or what your mechanic mate at such-and-such garage says cos, of course, both have commissioned independent tests and/or don't want you to buy their oil... Most people's oil recommendations are based on speculation rather than fact.

 

[S15RKM]

I use Halfrauds Fully Synthetic cause as Nicely says they are all about the same quality, its how often you change it that really matters,changing the filter at the same time of course:thumbs:

 

[BOOSTED]

I'd thought I'd just bump this old thread to ask a question but I found out the factory grade is 7.5w-30 (nissans special blend apparently) so I was thinking would 5w-30 be the best choice?

also the nissan oil is semi-synthetic where's I want to put in full, will it be ok if I just let the old oil drain out and then put in the new one or do you have to flush it with special stuff?

Because I heard you're not suppose to mix oil or something..


cheers

 

[StarletRick]

i personally use 5w30. royal purple if i can get hold of it. millers if not.

 

[BOOSTED]

yeah I was thinking of using rp 5w-30

 

[DeanS15]

i use millers cfs 5w40, stynthetics are a bit thinner but should offer more protection, especially if you have tuned the car....

 

[subzero]

wtf !! this thread has me confused .. i was recommneded 10w60 and have used it sdince. been recommended by a major tuner here .

over kill ??