Open front and rear differential conversion

Installation notes

• This route changes differential action. It does not preserve the original axle LSD function, and it does not convert the center differential.
• The rebuild route uses one ARA311094 pack for both axle units. The pack contains six small shims, six large shims and six 1.9mm open-diff spacers, enough for three differentials; the third pair is spare.
• Follow the OEM open diagram for the shim and spacer order. Remove the friction/star plate stacks, but retain the cross-shaft support pieces also supplied under ARA310984; do not discard every part bearing that kit number.
• Retain the sound ARA310983 29mm case, ARA310985 gears, ARA310981 outdrives, ARA310980 43T GP4 ring gears, cross shafts, bearings, O-rings and case hardware. Renew worn seals and gaskets during service.
• The complete ARA311066 route requires two sold units. Each is the 43T GP4 open axle differential, factory filled with 10,000cSt oil; it is an alternative to the shim rebuild, not an additional purchase.
• Retain the matching GP4 ARA310979 input gears. Do not combine these assemblies with the older straight-cut or spiral input gears from unrelated 6S revisions.
• Check free differential rotation and end play with the case screws fully secured. A binding assembly needs its shim stack and components corrected; loosening the case screws is not a documented repair.
• Oil is a tuning choice for a rebuilt open differential. The OEM complete assembly provides a 10,000cSt reference, not a claim that one viscosity is optimal for every use.
• Motor, ESC, radio, battery, center gearing, wheels and axle driveshafts remain at their existing specification. No higher voltage or measured durability/handling improvement is established.

Sources