Preventing Damage to DaimlerChrysler Ultradrive Automatics

DaimlerChrysler’s revolutionary A-604 Ultradrive electronic automatic transmission debuted in 1989 and quickly developed a reputation for disintegrating with alarming frequency. Much of the trouble stems from the then-revolutionary substitution of solenoids for a conventional hydraulic valve body and the use of a first generation learning algorithm that adapted shift patterns to driving style. Before diving into the dreaded ‘re and re’ of these units, try these two simple techniques. Start with a fluid and filter change. Chrysler itself originally certified Dexron as a top-up fluid, but Mopar 7176 or equivalent ATF +3 (+4 in later versions) is the only fluid to use. Then consider “reprogramming” the trans using Chrysler’s road test procedure. Sometimes, a vehicle shared by two or more drivers can cause the control electronics to become confused as it senses the different habits of each driver. There’s not much you can do about that, but you can at least take mechanical failure out of the picture. Advise an auxiliary transmission cooler and stay on top of fluid and filter change schedules with the A-604. It’s hated by many, but often, it’s just misunderstood.