OIL USE 5w - 30 or 15 w -50

EURO · Post by **EURO** » Tue Jan 25, 2005 4:00 pm

Many of you would be aware of my leaking car!

when i rang the old mechanic today he said that mitsubishis lived off 5w-30 oil, and that any other oil could cause the camseals / rocker cover seals to leak/sweat....

is this bollocks? as the oil that the new mechs have been using is 15w-50, which they said is more then fine for the conditions in aussie....

any thoughts on this?

Boris · Post by **Boris** » Tue Jan 25, 2005 4:50 pm

It's hard to relate, but I have heard of FTO's to have more oil leaks when using higher viscosity oils. It all kinda depends on the temperature of where you live/drive too... ei Brisbane or Hobart...

Personally i'm very happy with Castrol, Syntetic R, 5w 30...

Jono · Post by **Jono** » Tue Jan 25, 2005 6:17 pm

i sencond that,

castrol R 5w 30 is good stuff.

EURO · Post by **EURO** » Wed Jan 26, 2005 11:18 am

well if im in melbourne - but often i start the car at 5am to get to work when its colder, but if also gets to say 37 here.... so should be i be aiming to use a 5w - 30.... or would the 15w 50 be fine?

is the 15w - 50 considered a higher viscocity oil? thus it could have caused the engine to leak more? if thats the case, if i change oils again the engine could be fine or would the damage already have been done to the cam seals and rocker covers..etc

RichardH · Post by **RichardH** » Wed Jan 26, 2005 3:27 pm

Umm, I'm confused. A 30-weight oil is thinner than a 50-weight oil. What was the reason for the mechanic reckoning that more leaks would occur with a high-viscosity 50-weight oil?

I found with my wife's Magna AWD engine that it chewed through the "standard" 30-weight oil very badly (0.5 litre a fortnight). Once I moved to Mobil 1 5W-50 it no longer required topping up - not a drop for 7500km.

Ye Olde how-stuff-works link on oils...

http://auto.howstuffworks.com/question164.htm

- Rich

Breza · Post by **Breza** » Thu Jan 27, 2005 8:27 am

Hehehehe,

Having lived in both Brisbane and Hobart.............

I normally use Castrol Formula R Synthetic 5w-30 as this is what is recomended in the FTO Owners manual. Haven't had any issues directly related to the oil apart from the usual FTO oil leaks that most cars seem to get anyways.

Last time I had some work done down here in Hobart the mechanics replaced my oil with Motul 0w-40 which I assume is a bit better.............although as it is a slightly thicker oil the FTO doesn't seem to rev as freely.

Cheers

Chris

EURO · Post by **EURO** » Thu Jan 27, 2005 12:22 pm

for those interested.... i rang 2 mitsubishi dealers and a performance mechanic / importer.

All suggested that a 15 - 50 would be a better oil in Melbourne, but also said that really none of the oils should have an adverse effect, providing they are synthtic and of a good quality...

the performance importer said that the FTO being a non turbo would not need/want a really thin oil, and that they run 20/50 with the Fto's they have...

so I think the mechanic claiming that me using 15/50 would cause oil leaks in an FTO might be using an excuse to blame his shoddy work...

HiRAEdd · Post by **HiRAEdd** » Thu Jan 27, 2005 1:09 pm

I've just booked my car in for it's 65k service at Nihon and asked about the oils. Rick said he uses Fuchs Titan synthetic oil. I'm not sure on the specific one or weight but has anyone got anything good or bad to say about this oil?

Chiangstar · Post by **Chiangstar** » Thu Jan 27, 2005 1:58 pm

hmmm "Fuch's" ... how do you pronounce that

simon

HiRAEdd · Post by **HiRAEdd** » Thu Jan 27, 2005 3:58 pm

Ah fook it!

payaya · Post by **payaya** » Sat Jan 29, 2005 7:11 am

whats the point of a 0W# or 5W# in Australia??? I use somethnig in the range of 10W40 as our climate doesnt hit sub zero temps etc. I havent copped one leak ever in my car and maybe using thinner oils do cause leaks over time.

BuCkEt · Post by **BuCkEt** » Sat Jan 29, 2005 10:55 am

Doesn't hit sub zero temps???

You obviously have never been to Canberra in winter.

EURO · Post by **EURO** » Tue Feb 01, 2005 3:46 pm

Can anyone tell me.... What exactly engine blowby is and how it is caused.... could 'blowby' lead to oil leaks in an engine, how would the problem be rectified and why would this happen?

any help would be greatly appreciated.

payaya · Post by **payaya** » Sun Feb 06, 2005 7:28 am

everyone who considers castrol oil good do research and its pretty much crap!

Jono · Post by **Jono** » Sun Feb 06, 2005 4:17 pm

Castrol magnatech is crap...

but the castrol formula r series is good.

fto617 · Post by **fto617** » Mon Feb 07, 2005 12:12 am

i use to have a little leak of engine oil
but change to mobile 1 full synthetic 10W40
never leaked again and engine feels MUCH MUCH smoother compare to the castrol stuff u use before
i only used it cos it sounded nice the castrol stuff

seadog · Post by **seadog** » Mon Feb 07, 2005 2:04 am

Fuchs is good as used by Prodrive in their rally cars

Breza · Post by **Breza** » Wed Feb 09, 2005 8:22 am

Hey Guys,

There seems to be a few claims about what is a good brand of oil and what isn't. Apart from the viscosity debate........

Has anyone actually had their oil tested after having it drained? The results can tell you a lot about your car and the oil. Especially to compare apples with apples.

Haven't personally had it done on my FTO yet as I haven't found anyone to do the tests in Tassie and was too lazy when living in Queenland.

My oil was tested on my RS Turbo when I was running Amsoil and identified a few potential problems. From memory it was about $20 to get it tested.

Cheers

Chris

payaya · Post by **payaya** » Sat Feb 12, 2005 5:03 am

well i heard that tests were done on castrol oil and magnetec left dark burnt in oil on head etc.

Castrol oil was consistantly underperforming in oil pressure.

Cant remember where i read it but it was a while ago.

EURO · Post by **EURO** » Wed Feb 16, 2005 4:46 pm

Had another chat to mechanic today.

He swears by 5w - 30. He said all car manuals suggest it and that it decreases the wear on engine start signicicantly.

He was showing me a ford manual that shows up until 98 all the oils suggested varied from 5w-30, to 15w 50 etc, but after 98 they only suggest 5w-30.

the 5w-30 he uses was recommened for merc, porshe etc etc....
anyway, it was interesting but he was very strong in that my car should only use 5w-30. Said the free reving nature of the car as well as the temperature ranges, needed a thinner oil and that a thicker oil may lead to premature wear amongst engine internals...

sounded convincing....