[DieselFan]

Originally Posted by akshay1234

no. only when you change from mineral to synthetic or vice versa.

Wrong. One never changes from a synthetic back to mineral. It is a NO-NO. One should always scale to a higher grade else the engine will degenerate pretty quickly.

[Akshay1234]

Originally Posted by DieselFan

Wrong. One never changes from a synthetic back to mineral. It is a NO-NO. One should always scale to a higher grade else the engine will degenerate pretty quickly.

one shouldnt but what if we have to i.e no synthetic available or something. then its better to flush out the synthetic instead of adding mineral.

also can someone please confirm if mobil1 supersyn 5w50 will be fine on my diesel innova?

[Jaggu]

Its a good idea to use flush once in 20k to 25k kms on a regular basis but that doesnt mean engine flush is required every oil change (typically 7-12k kms)

Also there is no written rule that engine flush (like OWS) is required while shifting from Mineral to Synthetic, alternatives like regular flushing oil or a proper drain job will also do fine

[DieselFan]

Originally Posted by akshay1234

one shouldnt but what if we have to i.e no synthetic available or something. then its better to flush out the synthetic instead of adding mineral.

Flush out the synthetic? hilarious. You use a flush before switching to synthetic because synthetic have much higher detergent than mineral oil and we use flush as a precaution to remove all the muck in the engine before switching to synthetic. Else one must change the synthetic after 1000 or 2000 km of first fill.

flush is useless when switching from synthetic to mineral. Switching back to mineral oil is always risks. On doing so one risks the degeneration of engine at a rapid pace. Don't ever try it.

[Jaggu]

Coming to think of it, on a sparingly run engine (under 5 k kms) flushing oil does better job in removing the old oil residue.

[bluenest99]

Is Castrol edge also fully synthetic? How is it compared to Mobil 1. Suppose for any reason i change oil from Mobil 1 to castrol edge, do i need to flush again considering that both the brands are synthetic.

[Akshay1234]

gurus.. tsk etc.

mobil1 supersyn 5w50 meets the api cf grade. my diesel innova needs api cf or cf4. what i read is that cf4 is for heavy duty. my question is whether cf will work fine in my car even though it is used alot. more than 50km everyday. also revved to the redline sometimes. will it be safe using mobil1 supersyn api cf?

[Akshay1234]

or would delvac 5w40 be better?

[Jaggu]

@akshay: Both should work fine, Mobil 1 is fully synthetic and delvac is mineral.

Maybe users of Mobil 1 on diesel engines can give a better feedback on the difference. Am sticking to delvac with a more frequent oil change which is working out well in my Swift D

[Akshay1234]

actually on the mobil1 site it says delvac is also synthetic.

[Jaggu]

Originally Posted by akshay1234

actually on the mobil1 site it says delvac is also synthetic.

Thats interesting, could you share the link?

[tsk1979]

Originally Posted by akshay1234

gurus.. tsk etc.

mobil1 supersyn 5w50 meets the api cf grade. my diesel innova needs api cf or cf4. what i read is that cf4 is for heavy duty. my question is whether cf will work fine in my car even though it is used alot. more than 50km everyday. also revved to the redline sometimes. will it be safe using mobil1 supersyn api cf?

Go for Castrol GTX Diesel. (Not GTD). ITs API-CI4, a good 3 grades higher than API-CF. You will need to change oil every 6000kms or so since its a mineral oil, but the smoothness will be amazing.
But be aware this is a rare oil and you may have to scout many shops before you find it.
As for as synthetics, there are API-CI grade synthetic oils for diesels in the market. Search for those on mobil and Valvoline etc., websites.

[Akshay1234]

Originally Posted by tsk1979

Go for Castrol GTX Diesel. (Not GTD). ITs API-CI4, a good 3 grades higher than API-CF. You will need to change oil every 6000kms or so since its a mineral oil, but the smoothness will be amazing.
But be aware this is a rare oil and you may have to scout many shops before you find it.
As for as synthetics, there are API-CI grade synthetic oils for diesels in the market. Search for those on mobil and Valvoline etc., websites.

from whats given in this
http://www.team-bhp.com/forum/755987-post139.html

it shows that the innova only takes g-dld1, api-cf and cf4. are those minimum and are the the recommended ratings?

jaggu here is the link
Mobil Delvac 1 5W-40

[tsk1979]

API-CF is the minimum recommended. You can always exceed the recommended, no harm in that.

[Akshay1234]

Originally Posted by tsk1979

API-CF is the minimum recommended. You can always exceed the recommended, no harm in that.

oh cool.. then will delvac be fine if i can find it? otherwise will get castrol gtx diesel.