Best engine oil for Nissan FB15

[DeKay]

I have a Nissan FB15. Can anyone suggest me what would be the best engine oil for Nissan Fb which has the Nissan QG15 engine. Current mileage is about 230000. I've been using Mobil 10W 40 for past few years. Some people says that for this mileage its better to use more thicker oil than 10W 40 in order to reduce engine wear. 

Can anyone tell me if i use Mobil 15W 40 for this car? is it bad for the engine?

[Dushyantha]

Hi . welcome to the forum . u should first do a search on google regarding how the thickness of oils are named .You wouldnt have to increase the oil thickness if there isnt any noticeable oil burning in the engine . But the answer to an oil burning engine is not increasing the oil thickness . The correct way is to use the specific oil recommended in the owners manual and when the engine starts burning oil it means that its time for an engine overhaul . by using a more thicker oil you can avoid the overhaul for some time because the thicker oil would compensate for the worn out parts . usually crank bearings and piston rings but keep in mind that not all parts in an engine wear out evenly . so by using a thicker oil to compensate for the worn out parts you would be creating additional problems to non worn out parts which would still be needing a much thinner oil than thats required for the worn out parts . 

Using a sae30 oil in brand new engines and then using a thicker oil such as sae 40 when the mileage reaches somewhere around 100000 is practiced by most people in srilanka . this may have worked for older engines which may be more tolerant to oil thickness changes . but modern engines designers design these engines now keeping in mind that the users would strictly follow the instructions given . so using a different thickness oil in a modern engine would be inviting trouble IMO . so using a thicker oil is what would make you engine prone to wear much quicker . 

if sae 40 was used earlier better continue to use the oil of same thickness . 
And the 0W , 10W , 15W part really doesnt matter in srilanka . the number after the w is what you should be looking at to get an idea about the viscosity of oil . 

 

[The Stig]

17 hours ago, DeKay said:

I have a Nissan FB15. Can anyone suggest me what would be the best engine oil for Nissan Fb which has the Nissan QG15 engine. Current mileage is about 230000. I've been using Mobil 10W 40 for past few years. Some people says that for this mileage its better to use more thicker oil than 10W 40 in order to reduce engine wear. 

Can anyone tell me if i use Mobil 15W 40 for this car? is it bad for the engine?

As Dushyanath said the number behind w (20,30,40) determines viscosity and the number before determines the freezing point, warmup time etc. 

However he has missed a key point, in Sri Lankan Mobil oil context we only have 3 products in the w40 viscosity  which are 0w40, 10w40 and 15w40.

0w40 Is fully synthetic

10w40 is semi synthetic

15w40 is multigrade 

I would suggest to use 15w40 for now if you don't notice any oil burn in the car. 

[DeKay]

Thanks for the reply. I've noticed a small oil burning in my car. What if i use 10W 50? Will it cause for additional troubles?

[DeKay]

4 hours ago, The Stig said:

As Dushyanath said the number behind w (20,30,40) determines viscosity and the number before determines the freezing point, warmup time etc. 

However he has missed a key point, in Sri Lankan Mobil oil context we only have 3 products in the w40 viscosity  which are 0w40, 10w40 and 15w40.

0w40 Is fully synthetic

10w40 is semi synthetic

15w40 is multigrade 

I would suggest to use 15w40 for now if you don't notice any oil burn in the car. 

What's the different between 15w40 and 10w40?

[Dushyantha]

1 hour ago, DeKay said:

What's the different between 15w40 and 10w40?

the number after the W is what determines the viscosity . so theres not much of a difference between those two oils except for the way they are manufactured and the cold starting temperatures and stuff which in srilanka is not very important

1 hour ago, DeKay said:

Thanks for the reply. I've noticed a small oil burning in my car. What if i use 10W 50? Will it cause for additional troubles?

yes it would . a small oil burn if acceptable for an engine of that mileage . as i said earlier , using a higher viscosity oil on a worn out engine only solved problems temporarily an also cause more additional problems on the long run . things like the oil pump in your engine were not designed to pump oil of viscosity 50 so u wouldnt know what kind of problems would arise . use the correct oil and do an engine overhaul when the time comes . Thats the correct way to go . using a 50 oil on an engine designed for a 30 oil is not very wise . hence keep using the 40 oil and when you cannot run the engine anymore . do an overhaul .

[The Stig]

10 hours ago, Dushyantha said:

the number after the W is what determines the viscosity . so theres not much of a difference between those two oils except for the way they are manufactured and the cold starting temperatures and stuff which in srilanka is not very important

No! OP has clearly said he wants to use Mobil oil, you have not properly read my reply. The difference between 15w40 and 10w40 in "Sri lanakn" context is not cold temperatures and all the jazz. Yes it is very very important because in Sri Lanka Mobil 10w40 is semi synthetic and 15w40 is mineral oil. If you don't know what you are talking about please stop misguiding people. 

 

12 hours ago, DeKay said:

What's the different between 15w40 and 10w40?

In mobil context like I have said 15w40 is Multigrade mineral oil (normal oil)  and 10w40 is semi synthetic which means it's a mix of minerals and synthetic. If you have oil burn/leaks mineral oil is the way to go. Try using 15w40, it should slightly improve the oil burn since 10w40 you have been using is semi synthetic. 

[DeKay]

On 9/9/2016 at 8:28 AM, The Stig said:

 

 

In mobil context like I have said 15w40 is Multigrade mineral oil (normal oil)  and 10w40 is semi synthetic which means it's a mix of minerals and synthetic. If you have oil burn/leaks mineral oil is the way to go. Try using 15w40, it should slightly improve the oil burn since 10w40 you have been using is semi synthetic. 

 

WHy does everyone say that don't use mineral oil for car engines?

[Rumesh88]

Just now, DeKay said:

WHy does everyone say that don't use mineral oil for car engines?

Who says so? There is nothing wrong in using mineral oil based engine oil for cars and other vehicles.

[The Stig]

5 hours ago, DeKay said:

WHy does everyone say that don't use mineral oil for car engines?

Who is everyone ? 

However if people say not to use synthetic oil for older cars that makes perfect sense.