Gear lubes tested:

• AMSOIL Severe Gear 75w90
• Red Line Synthetic 75w90
• Lucas 75w90 Synthetic
• Valvoline high performance 80w90
• Castrol Hypoy C 75w90
• Valoline SynPower 75w90
• Castorl SYNTEC 75w90
• Pennzoil Synthetic 75w90
• Mobil 1 Synthetic 75w90
• Pennzoil Gearplus 80w90
• Mopar Synthetic 75w90 with Mopar LS additive
• GM synthetic axle 75w90
• Royal Purple Max Gear 75w90
• Torco SGO Synthetic 75w90 with Torco Type G LS additive

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