GMC 1995 Safari Owner's Manual page 246

Air Conditioning
Every now and then have your dealership check your air conditioning
system to be sure it has not lost any cooling ability. If you think the system
is not working properly, have your dealership check it out as soon as
possible.
The air conditioning will not work when the temperature is below 40°F
(4°C).
Lock Cylinders
To be sure your locks operate properly, they must be lubricated.
Refer to the Maintenance Schedule to determine how often to lubricate them
and what type of lubricant to use.
You should not use penetrating oils because they could wash out the factory
installed lubricant and cause the lock to bind. De-icers which contain
alcohol could also wash away the lubricant, so be sure to lubricate the lock
after using a de-icer of this type.
Exhaust System
To help prevent damage to your exhaust system, do not continue to drive
your vehicle if you notice:
Engine misfiring
Loss of performance
Exhaust system components hanging lower than normal.
Loud exhaust system noises.
Other unusual operating conditions
Have your engine and exhaust system serviced regularly.
Three- Way Catalytic Converter
Your vehicle's three-way catalytic converter is designed to reduce the
pollutants in your vehicle's exhaust. Use only unleaded fuel in your vehicle.
If you use leaded fuel, you could damage your three-way catalytic converter
and other engine components.
Engine Control Module System
This system has an oxygen (02) sensor that helps keep your engine's
air-fuel mixture at a proper level. Use only unleaded fuel in your vehicle. If
you use leaded fuel, you could damage your oxygen (02) sensor and affect
your vehicle's emissions.
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