quote:Oops, not true, John, at least according to Dave Granquist at Red Line. He told me in writing that the 5W-40 is RL's only oil to use viscosity-index improver and it uses about as much as dead-dino 5W-30 does.
Originally posted by JohnBrowning: Redline 5W40 does not use polmer thickners at all in the 5W40!
quote:Interesting...I had sort of decided to use their 10W-40 in the summer instead of their 5W-40, but your note caused me to look again at their specs. The FIVE-W-40 is slightly THICKER at 200dC than the 10W-40 (15.1 v. 14.6), while the 5W's base (40dC) viscosity is only slightly lower at 94 v. 98. (RL's 5W-30's base vis. of 65 is significantly lower than that of the 5W-40.) Obviously the 5-40 uses significantly thicker base stock than does the 5-30. I believe Dave's 'about as much as a dead-dino 5W-30' was oversimplified for me and that it does NOT use much VII. The HT/HS ratings of the 5-40 and 10-40 are virtually identical at 4.6 and 4.7. That 4.6 is 12% higher than that of M1's 5W-40 and 28% higher than that of M1's 0W-40, just another good reason to use RL intead of M1. I think the 5W-40 will be just fine for me all year 'round. I also think we're splitting hairs here, but as long as I have to buy my engineoil, I'll buy the best I can find. Dave R, don't be bashful about using the RL 5W-40 rather than the 10W-40; I'm not. [ March 09, 2004, 02:45 AM: Message edited by: Jeffrey Behr ]
Originally posted by JohnBrowning: It is so shear stable I wonder if Delvac-1 does the same! I would prefer not to have any VIIs. That is a lot of VIIs if it is on par with a dino 5W30!!! I might have to switch to their 10W-40 or 15W-40 for all but winter use!!!