GMC Sierra Denali Owner's Manual page 285

What Kind of Engine Oil to Use
Oils recommended for your vehicle can be identified by
looking for the starburst symbol.
This symbol indicates that the oil has been certified by
the American Petroleum Institute (API). Do not use
any oil which does not carry this starburst symbol.
If you choose to perform
the engine oil change
service yourself, be sure
the oil you use has the
starburst symbol on the
front of the oil container.
If you have your oil
changed for you, be sure
the oil put into your engine
is American Petroleum
Institute certified for
gasoline engines.
You should also use the proper viscosity oil for your
vehicle, as shown in the viscosity chart.
I
RECOMMENDED SAE VISCOSITI 6RADE ENGINE OILS
I
HOT
WEATHER
/ 7
"F
OC'
+ l o o -
-
+ 3 8
+ B O - - + 2 7
i . 6 0 - - + 1 6
+ 4 0 - -
+ 4
t 2 0
- -
- 7
0 - - - 1 8
I
COLD
WEATHER
LOOK
FOR MIS
j
SYMBOL
'
ACCEPTABLE
r
IF 5W-30 I S NOT
-30 AVAILABLE
RECOMMENDED
DO NOT USE SAE IOW-40, SAE 20W-50 OR ANY OTHER
MSCOSIWGRADE OIL NOT RECOMMENDED
5-1 6