Softail Oil Change
Softail Oil Change
Softail Oil Change
From time to time I see question on the forum regarding doing an oil change on a Harley and more
specifically about doing a scavenging oil change on a Softail. Since there didn't seem to be a good thread
on doing an oil change with pictures, I thought I would write something up. This oil change was done on
a 2001 Fat Boy. So, some of the tools and procedure may be different for your specific application.
Tools
Motorcycle lift
1/4" Allen head socket or long Allen head tool (for engine oil and transmission oil drain plugs)
3/8" Allen head socket or Allen head tool (transmission oil fill plug)
3/8" drive ratchet wrench
6" long 3/8" drive extension
3/8" drive universal joint (may or may not need depending on bike location on lift)
1/4" drive ratchet wrench
T27 Torx head socket or torx head tool (primary cover screws)
T40 Torx head socket or torx head tool (primary oil drain plug)
Oil filter wrench
Oil catch tool for filter (optional)
Oil drain pan (preferably 2)
Flashlight
3/8" Fuel / Oil line removal tool (Scavenging oil change ONLY)
Clear tygon tubing (Scavenging oil change ONLY)
Supplies
Oil for engine (3-4 quarts)
Oil for transmission (~ 1 quart)
Oil for primary (~ 1 quart)
O-rings for transmission and engine oil drain plugs (available from dealer for about $1 each)
Primary cover o-ring
Thread sealant for primary oil drain plug
Figure 1.
2. Next, remove the engine oil (oil tank) fill plug. This will make draining the oil tank go a little
faster. (Figure 2)
Figure 2.
Figure 3.
NOTE
On my bike the oil tank drain plug uses a 1/4" Allen head socket or Allen head tool. However, this may
be different on your bike.
Figure 4.
Figure 5.
Install a new o-ring on the oil tank drain plug and after the oil has stopped draining, install the
drain plug.
5. If you have a second drain pan available, remove the oil filter. Generally, removing the oil filter
is going to make a huge mess. However, you can improvise a tool to divert the oil away from the
engine and to the drain pan thus minimizing the mess. I made mine out of an old 2-liter soda
bottle with the bottom cut off and a slot to get the oil filter wrench to the oil filter. Pretty much
anything that will divert the oil away from the engine and still allow you to get the filter off will
work. (Figure 6, 7, and 8)
Figure 6
Figure 7.
Figure 8.
When you replace the oil filter, make sure that you lubricate the rubber seal on the new filter
with engine oil. This will prevent the filter from binding against the engine case and make for
easier filter removal during the next oil change.
6. The next step is to drain the transmission oil. First, remove the transmission oil fill plug. This will
make the transmission oil drain faster and ensures that you don't get caught with no oil in the
tranny should the fill plug be difficult to remove. On my bike, to remove the plug I needed a 3/8"
Allen head socket or Allen head tool. I use a 3/8" drive universal joint and 6" extension along
with a 3/8" Allen head socket to clear the rear exhaust pipe while removing the plug. (Figure 10 not yet available)
Figure 11.
Inspect the transmission oil drain plug for metal shavings just like you did with the engine oil
plug. Like the engine oil drain plug, it is normal to find a small amount of powdery material on
the plug. After all the transmission oil is drained install a new o-ring on the drain plug and install
the transmission oil drain plug.
Figure 12.
9. Locate the primary drain plug on the bottom of the primary housing, place a drain pan under the
primary, and remove the plug. On my bike, this requires a T40 Torx head tool. (Figure 13)
Figure 13.
After all of the primary oil has drained, apply a thread sealant to the primary drain plug and
install the plug. I use a Teflon tape sealant on the threads but, a liquid sealant will work also.
10. Next, refill the bike with the appropriate oil for each location. If you ask for opinions on what oil
to use, you'll get about a million different choices. Here's what I recommend:
Engine Oil / Oil Tank - 20W50 Synthetic
Transmission - 75W90 Synthetic
Primary - 20W50 Non-Synthetic (recommend by folks who installed my 6-speed gear set)
Again, this is just what I use. Folks have use many other (different) oils than this with equal
success. My only hard and fast recommendation is that you use synthetic oil in the engine.
Unlike most automobile engines, the oil in a Harley engine can sometimes see temperatures of
250F or higher. Most non-synthetic oils will start to experience some viscosity breakdown
above 180F and significant breakdown above 240F. One of the primary reasons synthetic oil
was developed was because of oil breakdown related failures of aircraft engines during WWII.
Beyond that, the key is not WHAT oil you choose but rather making sure that you change your
oil and filter religiously at regular intervals. It is my opinion that you should never go more than
7500 miles on an oil change (regardless of what type oil you're running). Personally, I change
mine every 5000 miles.
I will say that I did use 15W40 non-synthetic oil in my engine during break-in after engine
modifications. However, I wasn't running the engine like I normally would (i.e. beating it like it
owes me money) so the oil temperatures never got all that high.
Figure 14.
Figure 15.
Insert a 3/8" Fuel/Oil line removal tool around the oil line into the space between the plastic
insert fitting and the oil line. (Figure 16 and 17)
Figure 16.
Figure 17.
While holding the Oil line removal tool against the oil tank with one hand, use the other hand to
pull the oil line out of the oil tank. After you have pulled outward on the line about 1", the collar
on the oil line with hit that back of the removal tool. You can then stop holding the tool and pull
the line the rest of the way out of the oil tank. (Figure 18)
Figure 18.