More engine oil discussion.

[JimX]

I've read several oil articles, some contradicting the others, and some talked about in here. But I think we're about due for another one especially with the server crash and all

This came about because I went into Autobarn in Chatswood looking for some 10W-40 synthetic Motul oil, which a guy at Auburn Autobarn who also owned a Skyline had recommended for my car (mild R33 GTS-t). In the end I could only find 5W-40, but the "40" was the important number and I'm already running Castrol 5W-30 and I just wanted something a bit thicker for summer.

So I took it to the counter and asked for a filter as well, and the guy said "You're not going to put that oil in your Skyline are you?" and I said yes, and asked why he thought it was a bad idea. He said that it was too thin and I should be running at least 15W-50 oil. I told him that I had been running 5W-30 for the past year or so with no problems. He still seemed wary, and he said that the 40 oil should be ok as long as I don't do any track work or too many mods. I bought the 5W-40 oil anyway and I'll put it in soon.

So anyway it got me thinking - I have known for awhile that thicker oil is necessary for really powerful engines, but aside from that the thinner you go the better. But now it's got me thinking - where is the cutoff point to where you need to run thicker oil?

I know that the drag racing tomato farmer guy (forget his name) runs Castrol 15W-50 oil (the only mineral Formula R in their series) and his car is like over 1000hp. So I'm guessing that 5W-40 oil will be fine for my car which is

The funniest thing here is - Two different stores from the same franchise, and completely different advice from each store!

[KamikazeR33]

dude a guy at autobarn told me i needed a 15w50 and i tried it and it ran like an absolute slug.... i changed it back immediatly to a 5w40 and the car runs better than ever

u need to oil upto the turbo quicker so a thinner oil at startup is neccecary

[Jay95R33]

I'm pretty sure factory spec oil for the R33 GTS-t's is 7.5/40w.

It's too hard (and expensive) to find 7.5w oil unless you use the nissan stuff, so that's why most people go for 5 or 10w.

I wouldn't use 15w, it's just too thick....

Stick with the 5/40w I say

J

[cul202]

jimx

victory bray is the tomato farmer in question and his race car is and has been for many years sponsored by castrol. the engine is a 2500hp keith black that has an oil change every run... his oil his not really related to what we should be using.

i've used only 5-40 grade and am thinking of going to try the 10-40 as my oil pressure is pretty much always on 2 (8 max) on the factory gauge. it drops below to about 1.5 at hot idle. i'm thinking i stay with the same brand as the pressure never drops or peaks heavily.

15 - 50 is around what i ran in my old red motor!

[2rismo]

NO NO NO NO NO!!!!!!

dude, if you had ANY MOTOR AT ALL with clearances as big as some big hp v8's you'd be running the heavier stuff.

Clearances in our Jap, injected motors are dramatically smaller and as such, too thick an oil will root things (performance, eng life etc) remarkably!

I know a lot of guys that run 0W 40 in their cars.

Is thin - Is good!

Adrian

[Brody]

Im using castrol forumla-r 5-30, no complaints. Feels good, idles well. I prefer it over the 5-50 mobile 1 i had in there before.

[Boost King]

Me old HQ had a worn 253 in it, and to stop oil bruning, I was told to put a 40/70 oil., It was so god dammed thick, it stop the smuldering, but it reved so much slower. THe engine was working against the oil.

No much sooner anyway did that oil start slipping through and it was time for a engine rebuild.

Stay thin, unless you start loosing oil, go a grade up, because as your engine ages, the engine loosens up and thin oil will start to slip through the rings or valve guides.

So as long as you aint loosing oil, stick to a thin oil.

My 2 cents.

PB

[Guest RedLineGTR]

yep factory is 7.5-30w

u can get that type of oil from some places but it cost to much so its not worth it. Stuff that i would use is 5-40w 10-40w 10-50w at most i know of a highly modded GTR that uses 10-60w but when i used that in my car the oil pressure was way too high so i switched back to 5-40w..works fine...as for track days usally u chnage your oil before or after a track day anyways depends how hard u are driving to make sure everything is okay

[cul202]

Adrian,

obvious you read my post wrong or i worded it badly as you, after saying NO NO NO NO, said exactly what i said in your post, ie bray's oil close to what i ran in my red motor but NOT what you run in turbo jap motors.

sorry, i just hate being hinted to as a drastic idiot when i have been working on my own cars for close around 9yrs

i run helix ultra synthetic and my oil pressure never gets above 1/4 the way up the gauge. if thats normal for a skyline then cool but i'm used to oil that fluctuates pressure a bit more than that.

Ben

[cul202]

yeah i didn't word either of my replies all that well

oh well,

me good england, me speak you well..

anyway, anyone have any major grievances with helix ultra what ever it is (0-40 or 5-40 - i cant remember atm - stupid short term memory). The 5000km is up and was wondering in anyone can suggest any other oil sub $60

[Busky2k]

30wts are a lil thin for our damn hot summers. 40wt is pretty ideal for the amount of ks we have on our cars coupled with the hot heat. 50wts should only really be used in oil burning engines or if you do alot of track work. Our jap engines run very tight clearnances compared to aussie/usa cars so a 50wt is not really ideal IMO.

Dont worry JimX, 5W40 you got is pefectly good!

[Kinks]

5W-40 is probably good enough all year as long as you don't give the motor a hard time when it's hot (which is bad for it in ways besides lubrication anyway).

I wanted slightly thicker for summer but I'm sure 5W-40 will do OK.

Wouldn't really be keen on using a 0W oil though. You do need to have some viscocity!!

[JimX]

I was running 5W-30 up until now because it was close enough to factory spec. But the guy at Chatswood got me thinking, even though I didn't trust his advice of running 15W-50.

The factory spec of oil thickness is for a stock standard engine. Up the power and at some point you need to increase the viscosity. Not to mention thicker oil is needed for our hot summers. But even with that consideration I think the 5W-40 was a good choice, with 0W-40 or 10W-40 being ok as well (as is the general consensus).

I now think that 30 is the bare minimum thickness, with 40 being pretty good and anything more either there for track work or desert driving, or just a waste of power. If I was going to run a 50 weight oil it would be 5W-50 too, not 15W-50.

Oh and yeah thanks for reminding me of Victor Bray's name cul202

[JimX]

Originally posted by cul202

anyway, anyone have any major grievances with helix ultra what ever it is (0-40 or 5-40 - i cant remember atm - stupid short term memory). The 5000km is up and was wondering in anyone can suggest any other oil sub $60

The Motul 5W-40 oil I bought was called "8100 X-CESS" and was $55 from Autobarn. It's 100% synthetic and says that it's good for turbo cars on the back of the bottle. It's got a high level of detergent and so should be good for keeping carbon buildup off the inside of your engine.

[2rismo]

Was "NO NO NO"'ing to whoever the crocodile was that gave that advice to JimX

What I said after that was re-iterating what you said to make your point stronger.

All good!

Adrian

[Jimbo2000]

I bought the new mobil1 gold 10w-30 last weekend and havnt had time to fix it in yet due to the rain, will tell ya how it goes this weekend

damn expensive stuff though 80 bucks a pop

[Jimbo2000]

after reading this whole thread, is 10-30 too thick?

[JimX]

Lower numbers are thinner. So 30 is probably too thin

Well as I've said I've been using 30 for most of this year without any problems. It's mainly the extra heat of summer that's making me want to go thicker, and also now the extra power output I have.

[Jimbo2000]

so you think i should change it?

its that new gold stuff with "supersynth" (probably just a sham but i thought i'd try)

[JimX]

I think for $80 it's probably better quality than say Castrol 5W-30, but I'd still want to be changing it every 5000km and that is a hell of a lot of money to be spending every 5000km. Also at $80 I don't know how much of that money is going into quality and how much into the name. With the Castrol oil a lot of it is in the name, which is why I think the Motul oil I bought is better even though it costs around the same as Castrol's cheapest synth.

Yours should be ok, but I wouldn't flog it too hard on a hot day in summer. But then, I think I wouldn't do that anyway with any type of oil in the engine unless I had an oil cooler.

I've heard a few people say that "Gold" Mobil oil is overrated and overpriced. If you wanted to swap it, maybe try their 0W-40 or 5W-50.