another dead overdrive unit

Well if he read the owners manual it say don't tow in OD...reading is a way to save money..Oh yeah i have 1500 dodge that i have 130'000 miles still original trans i do light towing and have 4 wheeled it since new always with OD off and i change my fluid every 15;000 miles and it shifts great. And i also turn OD off when just driving around town on only for hwy..Hoping to see how long it will last.Shes old and ugly and i love driving her she handles well for a truck rides nice and it was love at first sight.318 OD 4x4 extended cab a/c and no other options.Hell it had am fm only when i bought her.