Torsen Differential Care and maintenance partly copied and updated from ace hobby.

Lubrication

Only use Torsen oil for lubrication. Do not use silicon oil, or other types of lubricant.

The gears only need to be kept lubricated during its operations. Do not put too much or fill the diff with Thorsen oil. Neither the amount of oil nor the weight of the oil has anything to do with the amount of limited slip action regulated by the Torsen diff.

Open the new Torsen differential by twisting and sliding off the anodized sleeve. Examine the amount of lubrication on the gears. The gears should appear wet (coated with Torsen oil), but no more than a coat of oil on the gears (no gathering of oil anywhere in the diff).

  • If the gears appears dry, drop a drop of Torsen oil on the gears while turning the Torsen Drive Joints by hand. Repeat this process until the gears are coated with oil.

    If there is oil gathered in the diff, slide the anodized sleeve off completely and drain the Torsen differential. When finished, make sure the gears are still coated with oil.

    •

    After making sure the diff gears have a coat of oil, slide the anodized sleeve back half way, drop 10 to 20 drops of oil into the diff, and slide the anodized sleeve all the way back onto the diff case. Now, the diff will have enough oil to keep the gears lubricated.

    Differential Seal

    The Torsen differentials are sealed with O-rings. One O-ring on each outdrive axle/joint. There are two types of Torsen cases: one with thread, one with two grooves.

  • For the double grooved case, an O-ring rests in each groove, and the Torsen sleeve slides over them to seal off the Torsen completely.

    For the threaded case, there are no O-rings. The Torsen sleeve is simply threaded onto the Torsen case. To seal this type of Torsen differential, a bead of silicone ATV (from local auto part store) needs to be placed on both ends of the case where the sleeve contacts the case. Make sure the silicone ATV does not enter the Torsen case and mix with the Torsen oil.

    • Installation

    Carefully pull out the Torsen diff Drive Joints, install the factory diff ball bearings, and slide the Torsen diff Drive Joints back into the diff.

    Install the Torsen diff with ball bearings into your car. Since the Torsen diff Drive Joints can slide out, make sure the space between the tip of dog/universal/CVD bone and Torsen diff Drive Joints is properly packed with O-rings or fuel tubing. This way, the bone pushes on the O-rings or fuel tubing which pushes in the Drive Joints and keeps them in the Torsen diff.

    Break-In

    With the new Torsen diff properly lubricated and installed, drive the car around with low to mid engine RPM’s for 3 tanks of gas. Do not break-in Torsen differentials on test stand or with wheels off the ground. Do not use full throttle during break-in.

    After break-in, take the Torsen diff out and clean it to discard any metal particles produced during break-in. For proper cleaning procedure, please refer to Maintainance section.

    Maintainance

    Clean the Torsen differential after 2 hours of run time.

    Remove the differential from car. Brush off any dirt. Check the O-rings on the oupt axles after every race and replace them on a "need to replace" basis. The O-rings for the case sealing don't need any special attention, cause there aren't any moving parts there. Spray wash the Torsen differential (with motor/brake cleaner). Air dry completely (left over cleaning residue or fluid will effect lubricating performance of Torsen oil). Lubricate the O-rings with Thorsen oil. Replace with new O-rings if any damage has occured. Lubricate the Torsen diff as instructed in Lubrication section.

    Replace all O-rings after a few hours of run time when optical damage is there.

    On Fioroni Japan Trac Torsen and Nuova Faor Thorsen, replace the shims after 2 hours of run time.

    King Pin Screws (on Fioroni Hyper Trac Torsen) and Shafts (on Fioroni Japan Trac Torsen or Nuova Faor Torsen) should be replaced around 10 hours of run time or when the Satellite Gear has worn into the King Pin Screws or Shafts.

    Planetary Gears, Satellite Gears, Sleeve, Case, Outdrive should be OK if the Torsen diff is properly maintained. If damaged, all parts in a Torsen diff are replaceable, and each part is sold separately.

    Sources: Fioroni- Nuova Faor- Ace Hobby