Tools and Materials:
* New gear oil: The correct type and quantity are crucial. Your owner's manual will specify this. Look for GL-1, GL-3, or GL-4 gear oil depending on your transmission. Get a little extra in case of spills.
* Drain pan: Large enough to hold the old gear oil.
* Socket wrench set: You'll need sockets to remove the drain and fill plugs. The sizes will vary depending on your transmission, but commonly used sizes include 1/2" and 3/4" drive sockets. Extension bars might also be necessary.
* Wrench: A box-end or open-end wrench might be needed for stubborn plugs.
* Funnel: To pour in the new gear oil.
* Jack and jack stands: Essential for safety. Never work under a vehicle supported only by a jack.
* Gloves: To protect your hands.
* Shop rags or paper towels: For cleanup.
* Torque wrench (optional but recommended): To ensure the drain and fill plugs are tightened to the correct specification (found in your owner's manual).
Procedure:
1. Safety First: Park your truck on a level surface, engage the parking brake, and chock the wheels. Wear safety glasses.
2. Locate the Drain and Fill Plugs: These are usually located on the bottom (drain) and side (fill) of the transmission case. They may be different sizes.
3. Jack Up the Truck: Safely jack up the front end of your truck high enough to comfortably access the transmission. Place jack stands under the frame rails for support before getting under the vehicle.
4. Drain the Old Gear Oil: Position the drain pan under the drain plug. Carefully remove the drain plug using the appropriate socket and wrench. Let the old oil drain completely. This can take a while.
5. Inspect the Old Oil: Check the condition of the old gear oil. If it's extremely dark, gritty, or smells burnt, it's a sign of potential problems.
6. Replace the Drain Plug: Once drained, clean the drain plug and reinstall it, tightening it to the manufacturer's specified torque (consult your owner's manual). Don't overtighten!
7. Fill the Transmission: Using a funnel, carefully pour the new gear oil into the fill plug. Refer to your owner's manual for the correct amount.
8. Check the Oil Level: Once you've added the specified amount, you may find a check hole or have to add oil until it begins to trickle out of the fill hole. The best method is detailed in your owner's manual.
9. Replace the Fill Plug: Tighten the fill plug to the manufacturer's specified torque.
10. Lower the Truck: Carefully lower the truck using the jack.
11. Dispose of the Old Oil: Take the used gear oil to a recycling center or auto parts store that accepts used oil.
Important Considerations:
* Transmission Type: The exact procedure might vary slightly depending on the specific type of manual transmission in your F-350. This information is generalized.
* Manual vs. Automatic: This guide is for manual transmissions only. Automatic transmissions have a different procedure.
* Owner's Manual: Your owner's manual is your best resource. Always consult it for specific details and recommendations.
This process involves working under a vehicle; if you are unsure about any part of this procedure, it's best to have a qualified mechanic perform the gear oil change. Improperly completing this task could damage your transmission.
