2014 Chevrolet Express 3500 Passenger Owner Manual - Page 280

10-30 Vehicle Care How to Check Lubricant What to Use Refer to Recommended Fluids and Lubricants on page 11-12 to determine what kind of lubricant to use. When the differential is at operating temperature (warm), add enough lubricant to raise the level to the bottom of the fill plug hole. What to Use Refer to Recommended Fluids and Lubricants on page 11-12 to determine what kind of lubricant to use. Noise Control System The following information relates to compliance with federal noise emission standards for vehicles with a Gross Vehicle Weight Rating (GVWR) of more than 4 536 kg (10,000 lbs). The Maintenance Schedule provides information on maintaining the noise control system to minimize degradation of the noise emission control system during the life of the vehicle. The noise control system warranty is given in the vehicle warranty booklet. These standards apply only to vehicles sold in the United States. Rear Axle When to Check Lubricant Refer to the Maintenance Schedule on page 11-3 to determine how often to check the lubricant. To get an accurate reading, the vehicle should be on a level surface. If you have the 1500 Series, the proper level is from 15 mm (5/8 in) to 40 mm (1 5/8 in) below the bottom of the fill plug hole. The proper level for the 2500 and 3500 Series is from 0 to 6 mm (1/4 in) below the bottom of the fill plug hole. Add only enough fluid to reach the proper level.