When designing a full traction differential replacement for the TRX-4, LockedUp RC wanted to make something indestructible, simple and cost effective. They also wanted a reasonable weight that still uses 3 bearings and of course offering a very, VERY tight fit to your axle shafts to eliminate slop. Lastly, they wanted "In Phase" outputs which can help to minimize drive train harmonics in CVD applications.
Keeping in mind all of those things LockedUp RC has come up with their latest creation ... the "FI Spool - TRX4".
This hardened steel axle spool is great for and TRX-4 that needs 100% traction, 100% of the time. These 1.34 oz spools are sure to get you through the toughest trails and have stood up to our worst abuse. They are "F*****g Indestructible ... hence "FI".
Replace wimpy pot metal "lockers" and plastic differential assembly with LockedUp's one piece "FI Spool" and prepare to conquer all!
These spools are designed to offer a tight fit with stock and aftermarket axle shafts. Their tests have shown that most stock shafts only require a hair of "love" for a perfect fit ... usually just a matter of forcing them in and out a few times. Other shafts (like our OT shafts) may require a bit of polishing to slide into the spool.
This "fitting" process is due to the variances among manufacturer measurements, tolerances, etc. This is the only way they were able to make these spools work with no slop for all the various shafts out there. Because of this, LockedUp RC suggest you test fit your axle shafts outside of the axle prior to final assembly.
Spools are sold individually and include a press in silicone plug so you can remove your shift cable.
We do suggest using Copper Anti Sieze Grease during installation.
This helps with shaft removal after extended periods of use.
We also suggest 5mm/10mm Shim Kit to remove excessive side to side play in your installation.
