Engine Oil and Engine Oil Additive

[codename47]

I am pretty sure that car your talking about is a diesel engine. you can always change the grade to premium quality engine oil.
Semi synthetic (blend) are okay ,when you buy a good quality ones says Magnatec with same 15w40 grade .
If you wana upgrade to better one go fully synthetic , they are expensive but much better , they don't penetrate in your engine's gaskets and all.
But ! If you goto Fully synethetic you won't be able to go back to your standard one.

Why you wana increase the grade to 20W40 ? you thinking to put a bigger turbo or what? Just curious

On my petrol turbo charged skyline I use 10W50 full synthetic

 

[Swapnil]

I am pretty sure that car your talking about is a diesel engine. you can always change the grade to premium quality engine oil.
Semi synthetic (blend) are okay when your buy a good quality ones says Magnatec with same 15w40 grade .
If you wana upgrade to better one go fully synthetic , they are expensive but much better , they don't penetrate in your engine's gaskets and all.
But but! If you goto Fully synethetic you won't be able to go back to your standard one.

Why you wana increase the grade to 20W40 ? you thinking to put a bigger turbo or what? Just curious

On my petrol turbo charged skyline I use 10W50 full synthetic

Yes it is a Turbocharged diesel. Not intending for any mods, I don't know whether it has any real scientific reason or not, but my knowledge lets me conclude that viscous oil is good in hot conditions and better for turbo. I may be wrong.

 

[codename47]

I never heard anyone putting 20w40 in their diesel engine
you might wana check this for your reference
HPR - Penrite Oil

there is the Diesel car's engine oil , click them and read what they actually means

 

[nickandre]

for diesel cars 15w40 is the right oil, for hot temperatures the number on the right i.e 40 is more important and more the better provided the car can take it, and the number on left shows the viscosity when cold the lesser the better provided the engine will support that.
since you have a high mileage engine and if you have never used synthetic or semi synth in it its better you stick with with mineral oil, since you may not find much benefits now, and synthetic oils may sometimes cause the oil seals to leak on higher mileage cars where synthetic oil was never used however current synth oils don't cause it but why to risk it.
synthetic oils are good for turbo charged engines.
so if you want to go for a thick oil find one like 15w50 or 20w50 but note you may find the engine kind of sluggish since the oil is thick and engine needs to work a tad more and cause the fe to drop by a tiny bit.
what has tata or the place you change your oil at been filling in?

i have a petrol engine verna. Yeah a thick oil is good for to climates, for which i can fill in a 'x'w50 where x can be either 0,5,10,15 or 20 but by doing so i will get my average down.
company fills in 15w40 but i wanted a thinner oil to get better mileage couldn't find a 5w30 so took 0w40 engine performs better and there is a slight increase in fe.
@codename in india we are limited to oils from mobil1( just 4-5 choices in it) shell, castrol, total, veedol.

 

[Swapnil]

for diesel cars 15w40 is the right oil, for hot temperatures the number on the right i.e 40 is more important and more the better provided the car can take it, and the number on left shows the viscosity when cold the lesser the better provided the engine will support that.
since you have a high mileage engine and if you have never used synthetic or semi synth in it its better you stick with with mineral oil, since you may not find much benefits now, and synthetic oils may sometimes cause the oil seals to leak on higher mileage cars where synthetic oil was never used however current synth oils don't cause it but why to risk it.
synthetic oils are good for turbo charged engines.
so if you want to go for a thick oil find one like 15w50 or 20w50 but note you may find the engine kind of sluggish since the oil is thick and engine needs to work a tad more and cause the fe to drop by a tiny bit.
what has tata or the place you change your oil at been filling in?

i have a petrol engine verna. Yeah a thick oil is good for to climates, for which i can fill in a 'x'w50 where x can be either 0,5,10,15 or 20 but by doing so i will get my average down.
company fills in 15w40 but i wanted a thinner oil to get better mileage couldn't find a 5w30 so took 0w40 engine performs better and there is a slight increase in fe.
@codename in india we are limited to oils from mobil1( just 4-5 choices in it) shell, castrol, total, veedol.

I've been filling Valvoline 15w40 all her life. And note, I did not have any cold start issues. The region I live in has extremely high temperatures in summers and low in winters. My query, which now seems to be answered is, whether using a 20w40 will have any positive impact on performance as in pickup, turbo spool?

 

[codename47]

Swapnil Xw40 , X determines how thin/thick it is

less x means thin , more means thick

Thicker is good too , engine will run smooth for sure but am not sure if they have recommended grade for DIESEL
In here you can get cuz here they are specially desgined for diesel and petrol engines.

 

[nickandre]

not much difference or none. 15 or 20 will onoy make a difference in cold weather starting, thicker oil would be 50 instead of 40.

 

[Swapnil]

'a'w'b' here, a means temp, lower/higher, depending on ambient temp, and b means viscosity.
Where ambient temp is 5-10, v use a 5w40/30 oil. On the same lines, can 20w40 not be used when ambient temp is 20?
Yes, valvoline has a 20w40 grade for turbo diesels.
Crucial period of lubrication is while starting engine, so 20w40 is what i think.

 

[nickandre]

crucial period demands oil to reach faster up the camshaft and lobes, a lower viscosity oil will reach faster whatever be the temperature, a 20w will also reach but if it gets very cold it will take time. but why do you want 20w40 over 15w40 it will only make a difference to cold starting which you won't find. But if the approvals are higher then your previous 15w40 it will surely make a difference.
I've 20w40 a try if its fine stick to it if not 15w40.

 

[Swapnil]

crucial period demands oil to reach faster up the camshaft and lobes, a lower viscosity oil will reach faster whatever be the temperature, a 20w will also reach but if it gets very cold it will take time. but why do you want 20w40 over 15w40 it will only make a difference to cold starting which you won't find. But if the approvals are higher then your previous 15w40 it will surely make a difference.
I've 20w40 a try if its fine stick to it if not 15w40.

I prefer 20w40 over 15w40 because of the extreme change in climate here. I believe the ambient temperature has certain effect on the engine. Month of February the climate changes extremely. It is a winter like climate for 1st week and then it moves up to 38+ till February end. I am just intending to say that on a summer morning, 20w40 can provide better lubrication at start-up than 15w40, as the latter would be too thin, given the hot climate. You can get Valvoline, Servo 20w40 grade oil. Will just give it a try. Having said that, I will shift to a 5w40 grade in winters, as it is too cool then.
During my last oil change, I had filled half a liter of Servo 20w40 to drive from my home to mechanic, and the engine felt smooth, quiet and quick, in that 5 kms drive itself.

 

[nickandre]

by the way 5w40 is an all weather grade it doesn't mean that it will be thin during start up in 38+ it changes viscosity, but it will be a synthetic oil, and I'm not sure if for one season you can use mineral and for another you use synthetic. But use whatever pleases you provided the manual has approvals for the grade.

 

[ravurus]

The suggested enginel oil for octavia Diesel is 5W30 and 5W40 for Petrol engines. 5W30 grade is not available in most brands and most service stations use 5W40 for diesel engines as well. Is it OK?. Please suggest

 

[nickandre]

i think there is shell helix ultra extra 5w30 just check if it has an approval for diesel engines. Mobil1 5w30 is available to but have to search a lot.
in the diesel line up i think 5w40 is the best you can use like mobil delvac synthetic.
5w30 is more of a petrol engine oil.

 

[Swapnil]

Another query. Which oil amongst the following 2?

Lubricants ::Valvoline Cummins::
Lubricants ::Valvoline Cummins::

 

[nickandre]

for diesel engines the first link is the newest api rating go in for that. the second link is an older api rating cf4/api sj while the newest is api-ch4(for diesel)/api sn(for petrol)