How To put fluid in your RC differentials

Need to rebuild your RC differentials? Here are the steps for building a diff for an 1/8 scale buggy, truggy, or most Monster trucks.

Here are the parts from the diff.
Dissembled diff

Start off by greasing the o-rings.
Grease the o-ring

Insert the o-ring into the diff. Make sure it is seated well its your main protection from leakage.
Insert the o-ring into the diff

Put bearing on and insert out drive. Be sure to grease outdrive for leak protection. The pin is what holds the outdrive in so don’t forget it.
Put bearing on and insert out drive

Assemble the inner gears, you will have two sets of these.
Assemble the inner gears

Insert the two sets of inner gears. The shafts that the gears rest on have grooves cut into them make sure they line up when inside the diff.
Insert the two sets of inner gears

Choose your fluids, they range from 1,000 wt (1k) all the way up to and beyond 100,000 wt (100k).
Diff fluid weights

Fill your diffs with your fluid, I went with 3,000 wt (3k). You want to fill them up to the cross section. I usually fill it to the cross section then add a little more because there are voids inside that don’t get filled right away.
Fill your diff to the cross section

When sealing the ring gear, I use some 1,000 wt oil and that seals it up well
sealing the ring gear

Thank you vbgagon for submitting this article.

Similar Posts