MONTHLY PMCS

Change engine oil and filter — use correct viscosity per current temperature range; dispose of properly

Service air cleaner — clean or replace filter element per restriction indicator reading

Drain and inspect fuel filter/water separator — replace element if contaminated or at service interval

Check coolant concentration — must be 50/50 antifreeze/water; test with refractometer

Inspect and clean battery — remove corrosion from terminals and tray; apply protective coating

Load test battery — must maintain 9.6V under load for 15 seconds at 0°F rating

Inspect all air brake lines, fittings, and chambers — no corrosion, cracks, or leaks

Check wheel bearing adjustment on all 4 wheels — repack if required

Inspect and lubricate door hinges, hatches, and latches — apply light oil or grease

Check transfer case fluid — inspect level and condition; change per service schedule

Inspect run-flat inserts — remove and inspect all 4 for cracking, deformation, or damage

Check differential fluid levels — front and rear; inspect seals and drain plugs