Mazda 626 1999 2.0 diesel service and maintenance
110 HP, 230 Nm, Manual gearbox, Front wheel drive (FWD)
Engine oil
Engine oil capacity: 4.7 litres (5 quarts)
Recommended oil type (Oil Viscosity Classification SAE) is 5W-30
Timing belt
Based on practical experience, recommended Mazda 626 2.0 timing belt change interval is 100,000 km when belt should be replaced, or at least periodically check the belt's condition after this mileage and replace it at the first sign of damage.
Running your car in aggressive environments (e.g. salt, sand, etc.) causes timing belt to degrade faster and reduces its lifespan; under such conditions, the belt may need to be replaced sooner.

Mazda 626 1999 Wagon 2.0 DiTD 1999 - 2002 Mazda 626 1999 technical data
Mazda 626 1999 owner reviews
Always consult your vehicle manufacturer's service manual for service intervals and specifications!