GMC 1998 Jimmy - Engine Oil Additives; When to Change Engine Oil

As shown in the chart, SAE 5W-30 is best for your
vehicle. However, you can use
SAE 1OW-30 if it's going
to be
0°F (- 18 "C) or above. These numbers on an oil
container show its viscosity, or thickness.
Do not use
other viscosity oils, such as SAE 20W-50.
NOTICE:
Use only engine oil with the American Petroleum
Institute Certified For Gasoline Engines
"Starburst" symbol. Failure to use the
recommended oil can result in engine damage not
covered by your warranty.
GM Goodwrench" oil meets all the requirements for
your vehicle.
If you are in an area where the temperature falls below
-20°F (-29"C), consider using either an SAE 5W-30
synthetic oil or an SAE OW-30 oil. Both will provide
easier cold starting and better protection for your engine
at extremely low temperatures.
Engine Oil Additives
Don't add anything to your oil. Your dealer is ready to
advise
if you think something should be added.
When to Change Engine Oil
If any one of these is true for you, use the short tripkity
maintenance schedule:
0
0
0
0
0
Most trips are less than 5 to 10 miles (8 to 16 km).
This is particularly important when outside
temperatures are below freezing.
Most trips include extensive idling (such as frequent
driving in stop-and-go traffic
j.
You operate your vehicle in dusty areas or off-road
frequently.
You frequently tow a trailer or use
a carrier on top of
your vehicle.
The vehicle is used for delivery service, police, taxi
or other commercial application.
Driving under these conditions causes engine
oil to
break down sooner. If any one of these is true for your
vehicle, then you need to change your oil and filter
every
3,000 miles (5 000 km) or 3 months -- whichever
occurs first.
If none of them
is true, use the long triphighway
maintenance schedule. Change the
oil and filter every
7,500 miles (12 500 km) or 12 months -- whichever
occurs first. Driving
a vehicle with a fully warmed
engine under highway conditions causes engine
oil to
break down slower.
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