If you want to keep an automatic transmission alive as long as possible, then you have to keep your clutch packs healthy. Contrary to what you might think, that smooth effortless shifting that happens stock is actually not the best thing in the world for your clutches. To make smooth shifts possible, a little slip has to happen to produce an almost effortless shift. This will wear out the clutches faster resulting in a rebuild before it's needed. Installing a shift kit to firm up the shifts by increasing line pressure will make your clutches very happy.
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