Feb 25, 2007 / B7510 = installing block heater #11 DieselPower Elite Member Joined Sep 30, 2006 Messages 2,756 Location Fairfield, PA Tractor JD 3020, JD 4230, JD 7410, JD 2440, MF 750, NH LS170 20w15. Can't say I have ever seen that viscosity either and I sell oil.