FLUID LEVEL CHECK
See Figures 1 and 2
The oil in the manual transmission should be checked at least every 15,000 miles (24,000 km) or every 12 months, and replaced every 25,000-30,000 miles (40,000-48,000 km) or every 24 months.
- With the truck parked on a level surface, remove the filler plug from the side of the transmission housing.
- If the lubricant begins to trickle out of the hole, there is enough. Otherwise, carefully insert your finger (watch out for sharp threads!) and check to see if the oil is up to the edge of the hole.
- If the oil level is low, add oil through the hole until the level is at the edge of the hole. Most gear lubricants come in a plastic squeeze bottle with a nozzle that eases this process. You can also use a common everyday kitchen baster.
- Install the filler plug and tighten it to 18-25 ft. lbs. (25-34 Nm). Run the engine and check for leaks.
DRAIN AND REFILL
See Figures 3, 4 and 5
Once every 30,000 miles (48,000 km) or every 24 months, the oil in the manual transmission should be changed.
- The transmission oil should be hot before it is drained. If the engine is at normal operating temperature, the transmission oil should be hot enough.
- Raise the truck and support it properly on jackstands so that you can safely work underneath.
You will probably not have enough room to work if the truck is not raised.
- The drain plug is located on the bottom of the transmission. Place a pan under the drain plug and remove it. Keep a slight upward pressure on the plug while unscrewing it, as this will keep the oil from pouring out until the plug is removed.
- Allow the oil to drain completely. Clean off the plug, then install and tighten it to 18-25 ft. lbs. (25-34 Nm).
- Remove the filler plug from the side of the transmission case. There is usually a gasket underneath this plug. Replace it if damaged.
- Fill the transmission with gear oil through the filler plug hole. Refer to the Capacities Chart for the amount of oil needed to refill your transmission.
- The oil level should come right up to the edge of the hole. You can stick your finger in to verify this. Watch out for sharp threads!
- Install the filler plug and gasket, then lower the truck and check for leaks. Dispose of (recycle) the old oil in a proper manner.
CHECKING WATER ENTRY 4WD Models Only
See Figure 6
After having driven in deep water or mud, the clutch housing should always be checked for water entry. There is a small rubber grommet at the bottom of the left-side leading edge of the transmission case where it mates with the rear of the engine block. Carefully pry it out and let any water that has collected in the clutch housing seep out. After all the water has drained, be sure to reinstall the grommet.