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Is it wise to use additives for the V8 overdrive and back axle?

Should EP90 oil have additives such as Molyslip, Slick 50 or Wynns added to the gearbox/overdrive and back axle on the MGBGTV8 was a question in the TechTorque series in Safety Fast!? The member seeking advice said "advertising and forums I've read state that they assist with reducing friction, wear and also reduce operating noise of gearboxes and especially reducing back axle whine". (Dec 12)

Using additives in the lubricant for the combined gearbox and overdrive unit is not recommended because the friction materials on the two cones in the
overdrive unit need to be able to wipe off any oil traces so the cone can grip. You should use a medium grade hypoy oil such as Castrol 85W/90 or Duckams Hypoid 90 or a current equivalent which meets the recommended specification MIL-L-2105 and you should not use an additive.

For the back axle the specification for the recommended lubricant is MIL-L 2105B so a higher performance lubricant like Castrol Hypoy 90B or Duckams Hypoid 90S or current equivalents is necessary. Some additives may be useful but you should avoid any additives that attack bronze because the differential thrust washers are made of bronze. The bronze baulk rings in the gearbox can also suffer.
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