Building a Front Spool from Tamiya Parts | ETRL

As we all know, both the Spec Truck and Super Truck classes use the TT-01 as the base platform. That truck has 2 options when it comes to the front differential; stock gear diff or optional ball diff.

There is a 3rd option, however - the spool. Some people have used he Yeah Racing Aluminum Front Solid Axle insert, but it's come to our attention that some of them are a little too 'tall', causing a slight warp in the differential gear. This can cause a slight bind in the drivetrain, resulting in overheating and melting parts.

After a little research, we found a front spool solution using genuine Tamiya parts. Check the parts list and follow along as we build one up for use in the Super Truck class (this option is not legal in the Spec Truck class).

Parts Needed:
• Stock differential
• Tamiya Part 9005422 (G Parts from the CC-01 - Part G5)

Step 1:

The first step is to disassemble the stock diff. Once apart, set aside the smaller satellite gears; these won't be used in the final build.

The 2 black parts in the middle are Part G5 from the CC-01.

Step 2:

Press the sun gears into Part G5. They should stay together; if not, a little drop of black grease will help keep them together.

Step 3:

Drop the star shaft into place; key the fingers into the slots in Part G5. Flip the two halves together to create the locker unit.

Step 4:

Drop the locker unit into the diff housing. They star shaft fingers will key to the slots in the housing.

Step 5:

Attach the diff gear.

Step 6:

That's it. Replace the bearings (not shown) and the outdrives and you've got an inexpensive locked front diff!

This is a super easy upgrade and, since these parts were designed to work together, you'll have a proper working locked differential.

Good luck!