1995 GMC Yukon Owner's Manual - Page 305

DIESEL ENGINES RECOMMENDED SAEVlSCOSlTY GRADE ENGINE OILS SELECT THE SAE GRADE 011 BASED O N THE EXPECTED TEMPERATURE RANBE BEFORE NEXT 011 CHANGE - HOT WEATHER 'lDO m n+38 +60 LOOK FOR THIS SYMBOL 15w40 - -+16 +32 -- 0 -I-- 0 -20 - - -18 SAE 15W-40 - 3 -29 PREFERRED above 0°F (-18°C) I I -SAE 30 - COLD WEATHER DO NOT USE SA€ 2OW-50 OR ANY OTHER GRADE OIL NOT RECOMMENDED SAE 1 SW-40 As shown in the viscosity chart, SAE ISW-40 is best for your vehicle. However, you can use SAE 1 OW-30 if it's going to be colder than 32°F (0°C) before your next oil change. When it's very cold, below 0°F (-1 8"C), you should use SAE 1OW-30 to improve cold starting. Also, SAE 30 may be used at temperatures above freezing,32°F (0°C). These numbers on the oil container show its viscosity, or thickness. Do not use other viscosity oils such as SAE IOW-40 or SAE 20W-50. 6-23