I know that the topic has already been discussed many times but in France we can't get the same motor oil in USA (brands and grade).
We have the following :
MOBIL 1 PEAK LIFE 5W50
CASTROL EDGE 10W60 : EDGE SPORT and EDGE TFT (not sure about the difference, TFT is newer than SPORT ???)
MOTUL 300V 5W40
MOTUL 300V 10W40
MOTUL 300V 15W50
The MOBIL 1 is made with POLYOLEFIN.
The CASTROL is enriched with ester.
The MOTUL 300V is double ester technology
The french specs are joined to this topic.
The spec are similar to those of the USA.
How can I optimize the use of the different oil based on the use of my car ?
The Shelby is not my daily car.
The temperature may drop to 32°F in winter and may increase up to 95°F in summer.
The range of the temperature is large.
I will go to the track during the good season.
What will be your recommendations ?
For the MOTUL 300V, if the winter number is too high (15W), can I start the engine safely if I wait for a few minutes before driving ?
If I use a high quality oil 5W40 or 10W40, the high number (40) for hot temp operation is lower than the Ford spec (50).
The others topics explain that the Motorcraft oil degrades rapidly after 2000 miles (the 5W50 becomes a 5W30)
On the other hand the high number (hot temp) for a high quality oil 5W40 or 10W40 stays at 40.
So a 15W50 will be very good for hot temp but what about the cold start.
During cold season, must I use a 5W40 and during warm season must I use a 15W50 or what is best to do ?
What do you think ?
Thank you for your help and advices.
I hope my english is understandable.
Edited by flo, 25 February 2012 - 06:24 AM.