Diff building.

I'm often asked questions about how I build my 1/8 diffs.  Is it important to grease the outdrive, O-rings, and ring gear?  How much grease should you use?  How much fluid should I put into the diff?  Hopefully this blog entry will help answer any questions you have about building diffs for your 8ight 3.0.  You can use the same method to build diffs on your SCTE 2.0, 8ight T 2.0 and 8ight E 2.0. 

It's always good to make sure all the parts are clean along with your work surface.  It's very important to grease the outdrive shaft, O-rings, ring gear, and the diff housing.  The grease will make the diffs operate smooth and be consistent on long runs.  If you don't grease these parts the silicone fluid can get between the outdrive and the ring gear and cause the two parts to seize or become notchy. 

You don't need too much grease, but it's better to have a little too much than not enough. 

Once you have the outdrive installed into the ring gear and diff housing you can install the gears.  I    like to tap on the cross pins to make sure they are pressed all the way into the diff housing. 

Next step is to fill the diff housing with silicone fluid.   

I fill the diff until the fluid completely covers the gears and cross pins. Then let the diff sit for a few minutes to let any air bubbles out of the oil. On the Team Losi Racing 8ight 3.0 I use 5,000 in the front, 7,000 in the center, and 3,000 in the rear. If the track is low grip, I switch to 5,000 in the center and 2,000 in the rear.

Next step is to drop the final gear into the diff housing

As you can see, there is too much fluid in the diff housing.  Make sure the gears are properly aligned. Then use your finger by pressing down firmly to wipe off the excess oil.

Here's how it should look after you wipe off the excess fluid.

Now you can attached the ring gear and install the diff.  I hope this helps!
Adam