Any thoughts on mixing different brands of Esther synthetic oils such as Gulf competition and Motul.
Also mixing different grades such as topping up 10w/40 Motul with a bit of 15w/50 Motul?
Any experts out there today?

 

generally speaking its a no-no, BUT ensuring you have oil in the motor is far safer than no oil so depends why you would consider it.................

at best you will dilute the "best" properties down to the lowest spec

and personally the only 2x ester based oils that are worth using are Millers CFS or Motul 300v...........

alyn

 

Cheers for your comments

 

what are you proposing or why??

 

I posed the question of mixing different grades of Millers CFS to Millers themselves (I had some 10/60 which I had used in the classic, when I had it, and 5/40 left over from an oil change on the newage) and they OK'd it.
I wonder if the resulting grade using equal amounts, would be 7.5/50

JohnD

 

Well I have a trackday tomorrow and currently have 2000 mile old Gulf 10w/40 in the car.
I also have 2.5 litres of Gulf 10w/40 and a couple of litres of Motul 10w/40 in the cupboard, so I am wondering if it would be better to stick with what I have or change the oil over today. I am not in a position to buy new oil today.
My standard procedure is to change oil before trackdays and then run that oil until the next track day or earlier if desired.
I put the last lot of oil in early December for a track day, but it was too wet, so used the wifes MR2 instead.
Therefore the Gulf oil has been used over 2000 miles of daily winter driving, which I figure is what an oil likes the least when it comes to longevity and contamination. I am not sure about the additives in this particular oil's ability to deal with said contaminants.
What do you think?

 

ps - I'm too lazy to change the filter over.

 

i use fuchs pro s. never heard bad things about it ever.what are your thoughts? not trying to start a debate just want to know your input

 

exactly as i have stated, in general terms the rest use inferior base stocks (and very few use ester) so a poorer quality
(all in my opinion but based on over 15yrs of being professionally involved in the tuning scene and a lot longer on the fringes)

alyn

 

It's absolutely fine to mix oils 99%+ of the time. The only issues are with a few plant based ones (biodegradeable and some ATFs, neither of which should be a concern for a scooby).

The only real issue with mixing oil is that one oil will often be lower quality than the other, so it would reduce the overall quality of the mix. If you are using two ester based oils, the quality will be similar, so no issue in mixing at all.

Cheers

Tim

 

Good - coz I did it anyways.
Cheers all the same.
ps what is the use-by date on your old label Motul 10w40, if you don't mind me asking.

 

The production date is March 2012, so it's not exactly old. Officially, Motul say it should be used within a couple of years of production, but off the record they say about 10 years.

Cheers

Tim

 

Sweet - I will put it on my birthday wish list ;-)