Thread: 10W-40
View Single Post
Old 01-24-2013, 02:49 AM   #25
smbrm
Senior Member
 
smbrm's Avatar
 
Join Date: May 2010
Drives: Scion FRS Ht Lva(AT)
Location: Alberta
Posts: 409
Thanks: 30
Thanked 81 Times in 54 Posts
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quote:
Originally Posted by serialk11r View Post
Right, I'm just speculating that at say 275F, a 50 weight still might not be "within spec". I haven't looked up any data but on BITOG there's a chart saying that 30 weight oil is about 3cSt at 300F, which is much thinner than the 7-8 cSt of 20 weight oil at 212F.

And even with synthetic you would want to be careful about oil temps since the oil does cool the piston and stuff like that which are much hotter than the average oil temp and can oxidize the oil quickly.
Not trying to be provocative, but I am curious as to what spec. you are referring to when you say "...still might not be within spec......"?
smbrm is offline   Reply With Quote