Engine Oil Additives/Engine Oil Flushes
Do not add anything to the oil. The recommended oils with the dexos specification and displaying the dexos certification mark are all that is needed for good performance and engine protection.
Engine oil system flushes are not recommended and could cause engine damage not covered by the vehicle warranty.
See also:
Reporting Safety Defects to the
United States Government
If you believe that your vehicle has a defect which
could cause a crash or could cause injury or
death, you should immediately inform the National
Highway Traffic Safety Administration (NHTSA)
...
Cruise Control Light
This light will come on
when the cruise control
is set. ...
Customer Assistance Offices
Buick encourages customers to call the toll-free
number for assistance. However, if a customer
wishes to write or e-mail Buick, the letter should be
addressed to:
United States — Customer Assist ...