Changing the Oil
Performing maintenance on your Stinger Gearbox is quite simple. One (1) quart of 75W-140 synthetic gear lube is needed, any name brand oil is acceptable; however we recommend Amsoil Severe Gear 75W-140 synthetic gear lube. It is available for sale here.
The gearbox has three plugs; a drain, sight, and fill. Really only the drain and fill hole need to be removed for service. Remove both aforementioned plugs, allow a few minutes for the oil to drain. During this time clean off the drain plug, then re-install (do not torque more than 25 ft/lbs.) Double check that the drain plug has been installed properly, then proceed to fill the gearbox with one (1) quart of 75W-140 synthetic gear lube. Re-install the fill plug (do not torque more than 25 ft/lbs.)
Stinger Drives Inc. recommends that the gear oil be changed every 40 hours or yearly. Whichever comes first.
The oil could last longer but we have found that 40 hour intervals really extend the life of the gearbox.