Differential fluid draining
Intro
While taking out the left CV axle from the Daihatsu Hijet to replace the CV boots, some differential fluid unfortunately started to slowly leak from the opening. I didn’t notice this until I went to re-install the CV axle and saw a small puddle on the ground. So rather than mix differential fluids, I opted to drain the old fluid and put in some fresh new stuff.
This fluid change is very straightforward and should only take about half an hour to complete.
Fluids and Tools Needed
- 24mm socket and ratchet
- 1 Quart of 80w90 gear fluid
- I had some 75W90 GL-4 Fluid left over that I used instead
Which Bolts?
To drain the front differential you just need access to two bolts located on the passenger side (front left since we in JDM land). Here are the location of the drain bolts:
Front differential drain bolt locations
The bottom bolt is the drain plug and the top bolt is the fill plug. To get easy access to these bolts you might need to remove the tire or the mud guard flap. I just opted to remove the mud flap:
Mud guard
This gave me enough room to be able to reach the bolts with a ratchet.
Pouring That Fluid
The service manual calls for 0.61 liters (0.64 quartz) of differential fluid. I however did not want to measure that specific amount so I just opted for pouring the differential fluid until it slowly started dripping out. Fill holes for these sort of things are lined up to where the suggested fill line is.
Since it was awkward getting the differential fluid bottle in a cramped space I developed a differential fluid delivery mechanism (patent pending):
Some high tech stuff here.
Fin
That is pretty much all to it. This guide is specifically for a S110P, but should be similar for other kei trucks.