The transmission system on the Harley-Davidson Evolution engine is located on the engine block, beneath the engine cover. Changing the transmission oil is a part of regularly scheduled maintenance that occurs every 50,000 to 60,000 miles or three years, depending on whichever comes first. Fresh transmission oil prevents the gears from grinding and the engine from overheating. Neglecting this maintenance can lead to costly engine damage. Fortunately, changing the transmission oil requires only a few tools and about an hour of your time.
1. Park the bike on a level surface and place it in a bike stand so it remains upright. If you don’t have a bike stand, have another person hold the bike upright while you change the transmission oil.
2. Remove the 10 screws that hold the engine cover in place, using the Phillips screwdriver. Place the cover and the screws in a safe location.
3. Locate the transmission on the right side of the engine. Place a collection pan beneath the drain bolt to catch the transmission oil as it comes out. Remove the drain bolt with the 18-mm socket wrench. Replace the drain bolt when the draining is complete.
4. Remove the transmission dipstick from the top of the transmission. Put a funnel in the dipstick tube. Pour in 1.5 quarts of transmission oil. Remove the funnel and reinsert the dipstick in the tube.
5. Reattach the engine cover.