I finally received the tech data for Castrol Syntec 5W-40. BMW High Performance Synthetic Oil is really the Castrol TXT Softec Plus 5W-30 with the specs listed below in German.
code:I posted this because in the past there was some confusion about the specs of these two oils. When the two oils are compared the only thing that stands out is the low flash point and very high HT/HS viscosity of the 5W-40. The Syntec 5W-40 is sold at some VW, Audi, Mercedes and Volvo dealers for about $5.00 a quart in the USA. As far as I know only BMW dealers sell this particular 5W-30 in the USA and it is usually sold for about $4.00. This oil is not the same as the regular Syntec 5W-30. The 5W-40 is rated ACEA A3, B3 and B4 and the 5W-30 is rated ACEA A3 and B3. The HT/HS of the 5W-30 should be about 3.5 or 3.6 since it is rated A3/B3. [ August 03, 2003, 02:41 AM: Message edited by: Sin City ]Castrol Syntec 5W-40 Specific Gravity, 60 F (15,5 C) (ASTM D1298) 0.85 Viscosity, cP @ 100 C (ASTM D5293) 12.80 Viscosity, cP @ -25 C (ASTM D5293) 3300 Max High Shear Viscosity, cP @ 150 C 4.5 Pour Point, C (ASTM D97) -33 Max Zinc, % Wt 0.10 Phosphorous, % Wt. 0.09 Flash Point COC, F (C) 405 (207) fire Point COC, F 430 (221) Sulphur, % Wt. 0.25 Viscosity Index 175 Total Base Number (TBN) 11 Below: Castrol TXT Softec Plus 5W-30 (AKA BMW High Performance Synthetic Oil 5W-30) Sorry this is in German and I can't translate all of this: Farbe 7,0- 9,0 Flammpunkt C 236 (ISO 2592) Dichte Bei 15 C 847,1 (DIN 51757 T4) Kin. Viskositat bei 40 C 68,1 (DIN 51562) Kin. Viskositat bei 100 C 11,9 (DIN 51562) CCS bei -25 3.1 DIN 51377 Total Base Number (TBN) 10 (ISO 3771) Viskositatsindex 173 (ISO 2909)