Team Associated RC8.2 – Build Report – Bag C – Front, Rear and Center Differential Assembly
Team Associated has always used us to have the differentials already assembled for us. This is no more the case for the RC8.2, we have to assemble the diffs ourselves. That’s the only negative (if it is one) point about the diffs. The rest is only good news. The new Team Associated RC8.2 includes new light weighted ring gears for all three diffs, new redesigned and light weighted the front and rear diff’s outdrives. The diff housing has been lightly redesigned too. It seems that AE has wanted a more lightweight drive train to increase acceleration and to reduce the overall weight of the buggy. The final drive ratio is still the same, 4.3:1.
Assembling the diffs is easy but it is a little time consuming. It is very important to pay close attention to details. Applying black grease (included in the kit) to every o-rings is very important. All three differentials use different outdrives. You can recognize the center diff’s outdrives by their flat shape used for the brake disks. The front and rear diffs use new outdrives that are almost identical. Pay a very close attention to the outdrives length. The front diff uses the longest outdrives while the rear diff uses the shortest ones. I have had to rebuild my front and rear diffs because I mixed up the outdrives!
Once the right outdrives for the right differential has been assembled, simply insert the spider gear assembly and add oil. Team Associated included a bottle of 5000wt diff oil for the three diffs. 5-5-5 is a very common diff setup for the RC8 buggies. Don’t overfill the diffs with oil. I usually stop filling the diff when oil level reaches 1mm above the spider gear. Rotate the diff to make sure oil goes everywhere in the diff and to eliminate air bubbles.
It is now time to close the diffs. I always apply a little amount of black grease on the ring gear where the gasket goes. This prevents the gaskets from moving when putting together both sections of the differential. I also use a screw to align all together the ring gear, gasket and diff housing. Evenly tight the four screws using an X pattern and rotate the diffs to make sure everything is spinning correctly. Differentials need a little time to spin freely and require a break in period. Once completely assembled, if the differentials are hard to turn or feel gritty, you can remove one or two shims located between the diff o-ring and the sun gear. Don’t run your buggy if a differential doesn’t spin freely. After few runs, all the differentials will be completely broken in. Reinspect them to make sure they are not too loose or too tight. You may add a shim if required.
To not confuse the front (long outdrives) and rear (short outdrives) diffs, take the time to identify them. This might save you frustration and precious time when it will be the time to install them into the buggy.
Want to set up diffs like a pro, check out my setup RC diffs guide!