According to expert testing and consumer reviews, there are several gear lubes that are the best for your vehicle and for the price. Torco SGO Synythetic is top among the gear lube brands, next in line is AMSOIL Severe Gear, and then finally Pennzoil-GM-Mobil are about neck and neck (price and power). According to the experts, you do not want to buy several brands which failed the gear lube product test; Red Line, Royal Purple and Lucas. These brands are not worth the price or, quite frankly, the time it takes to realize they are not working at top quality.