1997 GMC Sonoma Owner's Manual - Page 167

After Off-Road Driving Remove any brush or debris that has collected on the underbody, chassis or under the hood. These accumulations can be a firehazard. After operation in mud or sand, have the brake linings cleaned and checked. These substances cause can glazing and uneven braking. Check the body structure, and steering, suspension, wheels, tires exhaust system for damage. Also, check the fuel linesand cooling system for any leakage. Your vehicle will require more frequent service dueto off-road use. Refer to the Maintenance Schedule for additional information. Driving at Night Night driving is more dangerous than day driving. One reason is that some drivers are likely to be impaired -- by alcohol or drugs, with night vision problems,or by fatigue. 4-29