5w40 v 15w40

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Drago

Legendary Member
In our mild climate it makes little difference. As a general rool don't go more than one grade either way as the oil pump is designed to work with a particular viscosity.
 

madmadmax

Regular
Location
sheffiled
its abit more than the oil pump its the clerance on the big end and main barings as thats what sets the oil pressure if you put a pump on the system, so what i am saying running a 5w/40 may put the low oil pressure light on. run a good quolitey 15/40 if you whant to protect it.
 

Crankarm

Guru
Location
Nr Cambridge
Halfords are selling cheap 5w40 oil, my Nissan Micra uses 15w40.
Will the oil protect it's engine during the warm-up period?

If your Micra has covered a high mileage then I would definitely use a 15w/40 oil something like Castrol GTX or a Millers semi synthetic or a mineral oil. What does the Nissan car handbook state? If you are not too precious about it you could just chuck Halfords own brand in. Be sure to replace the oil filter though.

5w/40 oil will be too thin. Most 5w40 oils are semi or fully synthetic and used by more modern engines which if your Micra is old and high mileage is not what you want. Also as suggested it may result in low oil pressure which might mean that over time the engine runs a big end bearing. Result - end of engine or expensive rebuild.
 

biggs682

Touch it up and ride it
Location
Northamptonshire
imho 5w/40 will be fine given the info provided

but then I told Jeremy Clarkson to take that Porsche 928 and number plate to Argentina !
 
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gbb

Legendary Member
Location
Peterborough
I'd be very careful and bear in mind what |Screenman asks re mileage done.
I had a lovely Vectra SRI that was only really used locally and mostly short runs. The manual suggested going down a grade, that would give better economy, better cold engine running etc...so i did.
Within a year the engine developed a horrible rattle internally, like a bearing going. Not big end, it ran for a while till i got rid, so it wasnt terminal...but i did wonder if it was down to the thinner oil.
 

Pale Rider

Legendary Member
A lovely Vectra? Is there such a thing?

Not according to Clarkson, who once said the most interesting thing about the car was the dust cap on the valve.

Caused a lot of bother at the time, including a complaint from Vauxhall to the BBC.

Loads about it online, including this:

http://www.telegraph.co.uk/motoring/first-drives/2716596/Man-or-machine.html
 

gbb

Legendary Member
Location
Peterborough
A lovely Vectra? Is there such a thing?
^_^ I was waiting...
I am a Vauxhall man TBF. That car did me proud, it was comfortable, leather interior, fast when you wanted it, sedate if you wanted it, economical if you drove sensibly (easily 45mpg)...it was everything i need and want in a car.
Three years trouble free...then i started messing about with it (the oil)...shoulda left it alone (mind, the oil may not have been the reason).
 

Crankarm

Guru
Location
Nr Cambridge
I'd be very careful and bear in mind what |Screenman asks re mileage done.
I had a lovely Vectra SRI that was only really used locally and mostly short runs. The manual suggested going down a grade, that would give better economy, better cold engine running etc...so i did.
Within a year the engine developed a horrible rattle internally, like a bearing going. Not big end, it ran for a while till i got rid, so it wasnt terminal...but i did wonder if it was down to the thinner oil.

Errr ……… I am the one who raised the issue of mileage. A higher mileage means the engine might be more worn i.e. bearings. A new engine is much tighter as it is …… new. I would still go with what the oil rating the manufacturer recommends.
 

Pale Rider

Legendary Member
^_^ I was waiting...
I am a Vauxhall man TBF. That car did me proud, it was comfortable, leather interior, fast when you wanted it, sedate if you wanted it, economical if you drove sensibly (easily 45mpg)...it was everything i need and want in a car.
Three years trouble free...then i started messing about with it (the oil)...shoulda left it alone (mind, the oil may not have been the reason).

As you say, nice enough cars in the context of mass produced family hatchbacks.

Vauxhall had a point with Clarkson who criticised the car in the context of the much more expensive cars he liked at the time.
 

Crankarm

Guru
Location
Nr Cambridge
^_^ I was waiting...
I am a Vauxhall man TBF. That car did me proud, it was comfortable, leather interior, fast when you wanted it, sedate if you wanted it, economical if you drove sensibly (easily 45mpg)...it was everything i need and want in a car.
Three years trouble free...then i started messing about with it (the oil)...shoulda left it alone (mind, the oil may not have been the reason).

…. so if you put in a grade of oil other than that recommended by the manufacturer and the engine developed problems shortly after, then just maybe you are not the best person to be giving advice on oil perhaps, perhaps, perhaps?
 

gbb

Legendary Member
Location
Peterborough
:thumbsup:
…. so if you put in a grade of oil other than that recommended by the manufacturer and the engine developed problems shortly after, then just maybe you are not the best person to be giving advice on oil perhaps, perhaps, perhaps?

Errr...my words, copied and pasted..
I had a lovely Vectra SRI that was only really used locally and mostly short runs. The manual suggested going down a grade, that would give better economy, better cold engine running etc...so i did.
Within a year the engine developed a horrible rattle internally, like a bearing going. Not big end, it ran for a while till i got rid, so it wasnt terminal...but i did wonder if it was down to the thinner oil.

TBF, i didnt say WHY the manual suggested going down a grade, that was because i was a low distance, mostly town driver. Taxis were also included in that recommendation funnily enough, which did surprise me.

And its that very experience that makes me the PERFECT person to offer advice. TBF, it MAY not have been the oil, but what i offer errs on the side of safety, not the other way round :thumbsup:

I say manual, it was a Vauxhall tecnical publication...
 

gbb

Legendary Member
Location
Peterborough
Errr ……… I am the one who raised the issue of mileage. A higher mileage means the engine might be more worn i.e. bearings. A new engine is much tighter as it is …… new. I would still go with what the oil rating the manufacturer recommends.
Yes, you did. So did Screenman. :thumbsup:
 
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